From 6e28e76d2b4111e7764b821c2aade4222f01187c Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sat, 14 May 2022 23:42:03 +0530
Subject: [PATCH 01/19] add better name for printing names of parameterized
 test

---
 .../a5cc2925ca8258af241be7e5b0381edf30266302  |  0
 .idea/workspace.xml                           | 42 +++++++++++--------
 .../dbc/DuplicateCharactersCounterTest.java   |  2 +-
 3 files changed, 25 insertions(+), 19 deletions(-)
 create mode 100644 .idea/sonarlint/issuestore/a/5/a5cc2925ca8258af241be7e5b0381edf30266302

diff --git a/.idea/sonarlint/issuestore/a/5/a5cc2925ca8258af241be7e5b0381edf30266302 b/.idea/sonarlint/issuestore/a/5/a5cc2925ca8258af241be7e5b0381edf30266302
new file mode 100644
index 0000000..e69de29
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 76e3a07..12418b2 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,9 +4,7 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add sample input and sample output in the README.md">
-      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
-    </list>
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add links and citation" />
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -40,17 +38,17 @@
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent"><![CDATA[{
-  "keyToString": {
-    "RunOnceActivity.OpenProjectViewOnStart": "true",
-    "RunOnceActivity.ShowReadmeOnStart": "true",
-    "SONARLINT_PRECOMMIT_ANALYSIS": "true",
-    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary": "JUnit5",
-    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5": "",
-    "full.screen.before.presentation.mode": "true",
-    "settings.editor.selected.configurable": "editing.templates"
+  <component name="PropertiesComponent">{
+  &quot;keyToString&quot;: {
+    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
+    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
+    &quot;SONARLINT_PRECOMMIT_ANALYSIS&quot;: &quot;true&quot;,
+    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary&quot;: &quot;JUnit5&quot;,
+    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5&quot;: &quot;&quot;,
+    &quot;full.screen.before.presentation.mode&quot;: &quot;true&quot;,
+    &quot;settings.editor.selected.configurable&quot;: &quot;editing.templates&quot;
   }
-}]]></component>
+}</component>
   <component name="RecentsManager">
     <key name="CreateTestDialog.Recents.Supers">
       <recent name="" />
@@ -59,7 +57,7 @@
       <recent name="io.github.dbc" />
     </key>
   </component>
-  <component name="RunManager" selected="Java Scratch.Scratch">
+  <component name="RunManager" selected="JUnit.DuplicateCharactersCounterTest.shouldReturnMapOfCorrectSize">
     <configuration name="DuplicateCharactersCounterTest" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
       <module name="JCP_C1_P1" />
       <extension name="coverage">
@@ -132,9 +130,9 @@
     </configuration>
     <recent_temporary>
       <list>
+        <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnMapOfCorrectSize" />
         <item itemvalue="Java Scratch.Scratch" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest" />
-        <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnMapOfCorrectSize" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldThrowAnIllegalArgumentExceptionForNullInput" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnCount1ForNonDuplicat1Characters" />
       </list>
@@ -148,7 +146,7 @@
       <option name="number" value="Default" />
       <option name="presentableId" value="Default" />
       <updated>1652464472009</updated>
-      <workItem from="1652464473799" duration="2983000" />
+      <workItem from="1652464473799" duration="3459000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -234,7 +232,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652467935271</updated>
     </task>
-    <option name="localTasksCounter" value="13" />
+    <task id="LOCAL-00013" summary="add links and citation">
+      <created>1652468435970</created>
+      <option name="number" value="00013" />
+      <option name="presentableId" value="LOCAL-00013" />
+      <option name="project" value="LOCAL" />
+      <updated>1652468435970</updated>
+    </task>
+    <option name="localTasksCounter" value="14" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -262,7 +267,8 @@
     <MESSAGE value="add test case 4" />
     <MESSAGE value="add 1 more value for the first test" />
     <MESSAGE value="add sample input and sample output in the README.md" />
-    <option name="LAST_COMMIT_MESSAGE" value="add sample input and sample output in the README.md" />
+    <MESSAGE value="add links and citation" />
+    <option name="LAST_COMMIT_MESSAGE" value="add links and citation" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />
diff --git a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
index a884fe7..4f91fb2 100644
--- a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
+++ b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
@@ -17,7 +17,7 @@ void setUp() {
         counter = new DuplicateCharactersCounter();
     }
 
-    @ParameterizedTest
+    @ParameterizedTest(name = "countDuplicateCharacters(\"{arguments}\")")
     @ValueSource(strings = {"abcdefghijklmnopqrstuvwxyz", "dbc", "A", "1234567890", " "})
     @DisplayName("should return map of correct size")
     void shouldReturnMapOfCorrectSize(String input) {

From 55cb5deabcb885c40e6c2b6a888c4625a6ab0846 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sat, 14 May 2022 23:55:20 +0530
Subject: [PATCH 02/19] make test file read-only

---
 .idea/workspace.xml | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 12418b2..3323f63 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,7 +4,7 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add links and citation" />
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add better name for printing names of parameterized test" />
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -147,6 +147,7 @@
       <option name="presentableId" value="Default" />
       <updated>1652464472009</updated>
       <workItem from="1652464473799" duration="3459000" />
+      <workItem from="1652551743403" duration="710000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -239,7 +240,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652468435970</updated>
     </task>
-    <option name="localTasksCounter" value="14" />
+    <task id="LOCAL-00014" summary="add better name for printing names of parameterized test">
+      <created>1652551923621</created>
+      <option name="number" value="00014" />
+      <option name="presentableId" value="LOCAL-00014" />
+      <option name="project" value="LOCAL" />
+      <updated>1652551923621</updated>
+    </task>
+    <option name="localTasksCounter" value="15" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -268,7 +276,8 @@
     <MESSAGE value="add 1 more value for the first test" />
     <MESSAGE value="add sample input and sample output in the README.md" />
     <MESSAGE value="add links and citation" />
-    <option name="LAST_COMMIT_MESSAGE" value="add links and citation" />
+    <MESSAGE value="add better name for printing names of parameterized test" />
+    <option name="LAST_COMMIT_MESSAGE" value="add better name for printing names of parameterized test" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />

From b7b26fcee0f45f5e82bddf1c803b1142b9665f59 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sun, 15 May 2022 00:01:03 +0530
Subject: [PATCH 03/19] use the @NullSource and @EmptySource annotations for
 tests

---
 .idea/workspace.xml                           | 33 ++++++++++++-------
 .../dbc/DuplicateCharactersCounterTest.java   | 16 +++++----
 2 files changed, 30 insertions(+), 19 deletions(-)

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 3323f63..6a988bf 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,7 +4,7 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add better name for printing names of parameterized test" />
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="make test file read-only" />
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -22,10 +22,11 @@
     <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$" />
   </component>
   <component name="HighlightingSettingsPerFile">
+    <setting file="file://$APPLICATION_CONFIG_DIR$/scratches/scratch_54.java" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/pom.xml" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/src/main/java/io/github/dbc/DuplicateCharactersCounter.java" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/src/main/java/io/github/dbc/Main.java" root0="FORCE_HIGHLIGHTING" />
-    <setting file="file://$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" root0="SKIP_INSPECTION" />
   </component>
   <component name="MarkdownSettingsMigration">
     <option name="stateVersion" value="1" />
@@ -57,7 +58,7 @@
       <recent name="io.github.dbc" />
     </key>
   </component>
-  <component name="RunManager" selected="JUnit.DuplicateCharactersCounterTest.shouldReturnMapOfCorrectSize">
+  <component name="RunManager" selected="JUnit.DuplicateCharactersCounterTest.shouldReturnEmptyMapForEmptyInput">
     <configuration name="DuplicateCharactersCounterTest" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
       <module name="JCP_C1_P1" />
       <extension name="coverage">
@@ -73,7 +74,7 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="DuplicateCharactersCounterTest.shouldReturnCount1ForNonDuplicat1Characters" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
+    <configuration name="DuplicateCharactersCounterTest.shouldReturnEmptyMapForEmptyInput" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
       <module name="JCP_C1_P1" />
       <extension name="coverage">
         <pattern>
@@ -83,7 +84,7 @@
       </extension>
       <option name="PACKAGE_NAME" value="io.github.dbc" />
       <option name="MAIN_CLASS_NAME" value="io.github.dbc.DuplicateCharactersCounterTest" />
-      <option name="METHOD_NAME" value="shouldReturnCount1ForNonDuplicat1Characters" />
+      <option name="METHOD_NAME" value="shouldReturnEmptyMapForEmptyInput(java.lang.String)" />
       <option name="TEST_OBJECT" value="method" />
       <method v="2">
         <option name="Make" enabled="true" />
@@ -105,7 +106,7 @@
         <option name="Make" enabled="true" />
       </method>
     </configuration>
-    <configuration name="DuplicateCharactersCounterTest.shouldThrowAnIllegalArgumentExceptionForNullInput" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
+    <configuration name="DuplicateCharactersCounterTest.shouldThrowAnIllegalArgumentExceptionForNullInput (1)" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
       <module name="JCP_C1_P1" />
       <extension name="coverage">
         <pattern>
@@ -115,7 +116,7 @@
       </extension>
       <option name="PACKAGE_NAME" value="io.github.dbc" />
       <option name="MAIN_CLASS_NAME" value="io.github.dbc.DuplicateCharactersCounterTest" />
-      <option name="METHOD_NAME" value="shouldThrowAnIllegalArgumentExceptionForNullInput" />
+      <option name="METHOD_NAME" value="shouldThrowAnIllegalArgumentExceptionForNullInput(java.lang.String)" />
       <option name="TEST_OBJECT" value="method" />
       <method v="2">
         <option name="Make" enabled="true" />
@@ -130,11 +131,11 @@
     </configuration>
     <recent_temporary>
       <list>
+        <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnEmptyMapForEmptyInput" />
+        <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldThrowAnIllegalArgumentExceptionForNullInput (1)" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnMapOfCorrectSize" />
         <item itemvalue="Java Scratch.Scratch" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest" />
-        <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldThrowAnIllegalArgumentExceptionForNullInput" />
-        <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnCount1ForNonDuplicat1Characters" />
       </list>
     </recent_temporary>
   </component>
@@ -147,7 +148,7 @@
       <option name="presentableId" value="Default" />
       <updated>1652464472009</updated>
       <workItem from="1652464473799" duration="3459000" />
-      <workItem from="1652551743403" duration="710000" />
+      <workItem from="1652551743403" duration="1021000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -247,7 +248,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652551923621</updated>
     </task>
-    <option name="localTasksCounter" value="15" />
+    <task id="LOCAL-00015" summary="make test file read-only">
+      <created>1652552720625</created>
+      <option name="number" value="00015" />
+      <option name="presentableId" value="LOCAL-00015" />
+      <option name="project" value="LOCAL" />
+      <updated>1652552720625</updated>
+    </task>
+    <option name="localTasksCounter" value="16" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -277,7 +285,8 @@
     <MESSAGE value="add sample input and sample output in the README.md" />
     <MESSAGE value="add links and citation" />
     <MESSAGE value="add better name for printing names of parameterized test" />
-    <option name="LAST_COMMIT_MESSAGE" value="add better name for printing names of parameterized test" />
+    <MESSAGE value="make test file read-only" />
+    <option name="LAST_COMMIT_MESSAGE" value="make test file read-only" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />
diff --git a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
index 4f91fb2..fed1579 100644
--- a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
+++ b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
@@ -4,6 +4,8 @@
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.EmptySource;
+import org.junit.jupiter.params.provider.NullSource;
 import org.junit.jupiter.params.provider.ValueSource;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -41,17 +43,17 @@ void shouldReturnCount1ForNonDuplicateCharacters() {
         assertEquals(1, count, "the count value for all non duplicate characters should be 1");
     }
 
-    @Test
+    @ParameterizedTest
+    @NullSource
     @DisplayName("should throw an IllegalArgumentException for null input")
-    void shouldThrowAnIllegalArgumentExceptionForNullInput() {
-        assertThrows(IllegalArgumentException.class, () -> counter.countDuplicateCharacters(null));
+    void shouldThrowAnIllegalArgumentExceptionForNullInput(String input) {
+        assertThrows(IllegalArgumentException.class, () -> counter.countDuplicateCharacters(input));
     }
 
-    @Test
+    @ParameterizedTest
+    @EmptySource
     @DisplayName("should return empty map for empty input")
-    void shouldReturnEmptyMapForEmptyInput() {
-        // Arrange
-        String input = "";
+    void shouldReturnEmptyMapForEmptyInput(String input) {
         // Act
         var characterIntegerMap = counter.countDuplicateCharacters(input);
         // Assert

From 4f15b286e10b816b3475445fcf94d8acc4950ad2 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sun, 15 May 2022 00:48:28 +0530
Subject: [PATCH 04/19] add the name of the problem

---
 .idea/workspace.xml | 7 ++++++-
 README.md           | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 3323f63..c9ea1fe 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,7 +4,9 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add better name for printing names of parameterized test" />
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add better name for printing names of parameterized test">
+      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+    </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -22,6 +24,7 @@
     <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$" />
   </component>
   <component name="HighlightingSettingsPerFile">
+    <setting file="file://$APPLICATION_CONFIG_DIR$/scratches/scratch_54.java" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/pom.xml" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/src/main/java/io/github/dbc/DuplicateCharactersCounter.java" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/src/main/java/io/github/dbc/Main.java" root0="FORCE_HIGHLIGHTING" />
@@ -148,6 +151,8 @@
       <updated>1652464472009</updated>
       <workItem from="1652464473799" duration="3459000" />
       <workItem from="1652551743403" duration="710000" />
+      <workItem from="1652552767032" duration="13000" />
+      <workItem from="1652555356575" duration="289000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
diff --git a/README.md b/README.md
index 4d7bda0..203fcd9 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 
 ---
 
-### Problem Statement
+### Problem Statement : Counting Duplicate Characters
 
 Write a program that counts duplicate characters from a given `String`.
 

From d12e90bd468ef44cd9b9eb7e8d77193ae97c3681 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sun, 15 May 2022 22:24:22 +0530
Subject: [PATCH 05/19] add proper test names

---
 .../442292b8a7efeabbe4cc176709b833b1792140ec  |  0
 .../ed67eb178d523a4b3f117dcbe0eda5196367ceec  |  0
 .idea/workspace.xml                           | 49 ++++++++++++-------
 .../dbc/DuplicateCharactersCounterTest.java   |  4 +-
 4 files changed, 34 insertions(+), 19 deletions(-)
 create mode 100644 .idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec
 create mode 100644 .idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec

diff --git a/.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec b/.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec
new file mode 100644
index 0000000..e69de29
diff --git a/.idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec b/.idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec
new file mode 100644
index 0000000..e69de29
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 6a988bf..cff8988 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,7 +4,11 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="make test file read-only" />
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="use the @NullSource and @EmptySource annotations for tests">
+      <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" afterDir="false" />
+    </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -26,7 +30,7 @@
     <setting file="file://$PROJECT_DIR$/pom.xml" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/src/main/java/io/github/dbc/DuplicateCharactersCounter.java" root0="FORCE_HIGHLIGHTING" />
     <setting file="file://$PROJECT_DIR$/src/main/java/io/github/dbc/Main.java" root0="FORCE_HIGHLIGHTING" />
-    <setting file="file://$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" root0="SKIP_INSPECTION" />
+    <setting file="file://$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" root0="FORCE_HIGHLIGHTING" />
   </component>
   <component name="MarkdownSettingsMigration">
     <option name="stateVersion" value="1" />
@@ -39,17 +43,18 @@
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent">{
-  &quot;keyToString&quot;: {
-    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
-    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
-    &quot;SONARLINT_PRECOMMIT_ANALYSIS&quot;: &quot;true&quot;,
-    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary&quot;: &quot;JUnit5&quot;,
-    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5&quot;: &quot;&quot;,
-    &quot;full.screen.before.presentation.mode&quot;: &quot;true&quot;,
-    &quot;settings.editor.selected.configurable&quot;: &quot;editing.templates&quot;
+  <component name="PropertiesComponent"><![CDATA[{
+  "keyToString": {
+    "RunOnceActivity.OpenProjectViewOnStart": "true",
+    "RunOnceActivity.ShowReadmeOnStart": "true",
+    "SONARLINT_PRECOMMIT_ANALYSIS": "true",
+    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary": "JUnit5",
+    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5": "",
+    "full.screen.before.presentation.mode": "false",
+    "last_opened_file_path": "C:/Users/divya/Exercism/java/need-for-speed",
+    "settings.editor.selected.configurable": "reference.settingsdialog.IDE.editor.colors.Color Scheme Font"
   }
-}</component>
+}]]></component>
   <component name="RecentsManager">
     <key name="CreateTestDialog.Recents.Supers">
       <recent name="" />
@@ -58,7 +63,7 @@
       <recent name="io.github.dbc" />
     </key>
   </component>
-  <component name="RunManager" selected="JUnit.DuplicateCharactersCounterTest.shouldReturnEmptyMapForEmptyInput">
+  <component name="RunManager" selected="JUnit.DuplicateCharactersCounterTest">
     <configuration name="DuplicateCharactersCounterTest" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
       <module name="JCP_C1_P1" />
       <extension name="coverage">
@@ -131,11 +136,11 @@
     </configuration>
     <recent_temporary>
       <list>
+        <item itemvalue="JUnit.DuplicateCharactersCounterTest" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnEmptyMapForEmptyInput" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldThrowAnIllegalArgumentExceptionForNullInput (1)" />
         <item itemvalue="JUnit.DuplicateCharactersCounterTest.shouldReturnMapOfCorrectSize" />
         <item itemvalue="Java Scratch.Scratch" />
-        <item itemvalue="JUnit.DuplicateCharactersCounterTest" />
       </list>
     </recent_temporary>
   </component>
@@ -148,7 +153,9 @@
       <option name="presentableId" value="Default" />
       <updated>1652464472009</updated>
       <workItem from="1652464473799" duration="3459000" />
-      <workItem from="1652551743403" duration="1021000" />
+      <workItem from="1652551743403" duration="2511000" />
+      <workItem from="1652622259082" duration="160000" />
+      <workItem from="1652631231540" duration="1068000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -255,7 +262,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652552720625</updated>
     </task>
-    <option name="localTasksCounter" value="16" />
+    <task id="LOCAL-00016" summary="use the @NullSource and @EmptySource annotations for tests">
+      <created>1652553063899</created>
+      <option name="number" value="00016" />
+      <option name="presentableId" value="LOCAL-00016" />
+      <option name="project" value="LOCAL" />
+      <updated>1652553063899</updated>
+    </task>
+    <option name="localTasksCounter" value="17" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -286,7 +300,8 @@
     <MESSAGE value="add links and citation" />
     <MESSAGE value="add better name for printing names of parameterized test" />
     <MESSAGE value="make test file read-only" />
-    <option name="LAST_COMMIT_MESSAGE" value="make test file read-only" />
+    <MESSAGE value="use the @NullSource and @EmptySource annotations for tests" />
+    <option name="LAST_COMMIT_MESSAGE" value="use the @NullSource and @EmptySource annotations for tests" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />
diff --git a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
index fed1579..1489a67 100644
--- a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
+++ b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
@@ -43,14 +43,14 @@ void shouldReturnCount1ForNonDuplicateCharacters() {
         assertEquals(1, count, "the count value for all non duplicate characters should be 1");
     }
 
-    @ParameterizedTest
+    @ParameterizedTest(name = "countDuplicateCharacters({arguments})")
     @NullSource
     @DisplayName("should throw an IllegalArgumentException for null input")
     void shouldThrowAnIllegalArgumentExceptionForNullInput(String input) {
         assertThrows(IllegalArgumentException.class, () -> counter.countDuplicateCharacters(input));
     }
 
-    @ParameterizedTest
+    @ParameterizedTest(name = "countDuplicateCharacters(\"{arguments}\")")
     @EmptySource
     @DisplayName("should return empty map for empty input")
     void shouldReturnEmptyMapForEmptyInput(String input) {

From 4878cb773426e485674596c55b3ea7b1d23d4b8e Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sun, 15 May 2022 23:48:39 +0530
Subject: [PATCH 06/19] add suggested reading

---
 .../863e0292fd7e9b3e74dafd6cc01f73ba76346482  |  0
 .../8a6dae537be9f47878c6964c6ee40cab0ca75e28  |  0
 .idea/sonarlint/issuestore/index.pb           |  5 +++
 .idea/workspace.xml                           | 41 +++++++++++--------
 README.md                                     |  9 +++-
 5 files changed, 38 insertions(+), 17 deletions(-)
 create mode 100644 .idea/sonarlint/issuestore/8/6/863e0292fd7e9b3e74dafd6cc01f73ba76346482
 create mode 100644 .idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28

diff --git a/.idea/sonarlint/issuestore/8/6/863e0292fd7e9b3e74dafd6cc01f73ba76346482 b/.idea/sonarlint/issuestore/8/6/863e0292fd7e9b3e74dafd6cc01f73ba76346482
new file mode 100644
index 0000000..e69de29
diff --git a/.idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28 b/.idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28
new file mode 100644
index 0000000..e69de29
diff --git a/.idea/sonarlint/issuestore/index.pb b/.idea/sonarlint/issuestore/index.pb
index e69de29..ff5edbe 100644
--- a/.idea/sonarlint/issuestore/index.pb
+++ b/.idea/sonarlint/issuestore/index.pb
@@ -0,0 +1,5 @@
+
+w
+G.idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec,8\a\8a6dae537be9f47878c6964c6ee40cab0ca75e28
+w
+G.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec,8\6\863e0292fd7e9b3e74dafd6cc01f73ba76346482
\ No newline at end of file
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index cff8988..33f4569 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,10 +4,10 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="use the @NullSource and @EmptySource annotations for tests">
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add proper test names">
       <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -43,18 +43,18 @@
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent"><![CDATA[{
-  "keyToString": {
-    "RunOnceActivity.OpenProjectViewOnStart": "true",
-    "RunOnceActivity.ShowReadmeOnStart": "true",
-    "SONARLINT_PRECOMMIT_ANALYSIS": "true",
-    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary": "JUnit5",
-    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5": "",
-    "full.screen.before.presentation.mode": "false",
-    "last_opened_file_path": "C:/Users/divya/Exercism/java/need-for-speed",
-    "settings.editor.selected.configurable": "reference.settingsdialog.IDE.editor.colors.Color Scheme Font"
+  <component name="PropertiesComponent">{
+  &quot;keyToString&quot;: {
+    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
+    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
+    &quot;SONARLINT_PRECOMMIT_ANALYSIS&quot;: &quot;true&quot;,
+    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary&quot;: &quot;JUnit5&quot;,
+    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5&quot;: &quot;&quot;,
+    &quot;full.screen.before.presentation.mode&quot;: &quot;false&quot;,
+    &quot;last_opened_file_path&quot;: &quot;C:/Users/divya/Exercism/java/need-for-speed&quot;,
+    &quot;settings.editor.selected.configurable&quot;: &quot;reference.settingsdialog.IDE.editor.colors.Color Scheme Font&quot;
   }
-}]]></component>
+}</component>
   <component name="RecentsManager">
     <key name="CreateTestDialog.Recents.Supers">
       <recent name="" />
@@ -155,7 +155,8 @@
       <workItem from="1652464473799" duration="3459000" />
       <workItem from="1652551743403" duration="2511000" />
       <workItem from="1652622259082" duration="160000" />
-      <workItem from="1652631231540" duration="1068000" />
+      <workItem from="1652631231540" duration="1640000" />
+      <workItem from="1652638374278" duration="312000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -269,7 +270,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652553063899</updated>
     </task>
-    <option name="localTasksCounter" value="17" />
+    <task id="LOCAL-00017" summary="add proper test names">
+      <created>1652633662838</created>
+      <option name="number" value="00017" />
+      <option name="presentableId" value="LOCAL-00017" />
+      <option name="project" value="LOCAL" />
+      <updated>1652633662838</updated>
+    </task>
+    <option name="localTasksCounter" value="18" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -301,7 +309,8 @@
     <MESSAGE value="add better name for printing names of parameterized test" />
     <MESSAGE value="make test file read-only" />
     <MESSAGE value="use the @NullSource and @EmptySource annotations for tests" />
-    <option name="LAST_COMMIT_MESSAGE" value="use the @NullSource and @EmptySource annotations for tests" />
+    <MESSAGE value="add proper test names" />
+    <option name="LAST_COMMIT_MESSAGE" value="add proper test names" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />
diff --git a/README.md b/README.md
index 203fcd9..3bd4ca1 100644
--- a/README.md
+++ b/README.md
@@ -29,4 +29,11 @@ Write a program that counts duplicate characters from a given `String`.
 ---
 > Question taken from the book
 > ["Java Coding Problems"](https://www.packtpub.com/product/java-coding-problems/9781789801415) by Anghel Leonard.  
-> Formatted and uploaded by [dbc2201](https://github.com/dbc2201)
\ No newline at end of file
+> Formatted and uploaded by [dbc2201](https://github.com/dbc2201)
+
+---
+
+**Suggested Reading:**
+
+1. [HashMap (Java SE 18 & JDK 18)](https://docs.oracle.com/en/java/javase/18/docs/api/java.base/java/util/HashMap.html)
+2. [Managing the Content of a Map (dev.java)](https://dev.java/learn/managing-the-content-of-a-map/)
\ No newline at end of file

From cf908479843df088d9eb7a0cad4c77776a447861 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sun, 15 May 2022 23:49:25 +0530
Subject: [PATCH 07/19] add sonarlint to gitignore

---
 .gitignore                                                   | 5 ++++-
 .../issuestore/a/5/a5cc2925ca8258af241be7e5b0381edf30266302  | 0
 2 files changed, 4 insertions(+), 1 deletion(-)
 delete mode 100644 .idea/sonarlint/issuestore/a/5/a5cc2925ca8258af241be7e5b0381edf30266302

diff --git a/.gitignore b/.gitignore
index 5ff6309..9f91b2d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,4 +35,7 @@ build/
 .vscode/
 
 ### Mac OS ###
-.DS_Store
\ No newline at end of file
+.DS_Store
+
+### SonarLint ###
+.idea/sonarlint/
\ No newline at end of file
diff --git a/.idea/sonarlint/issuestore/a/5/a5cc2925ca8258af241be7e5b0381edf30266302 b/.idea/sonarlint/issuestore/a/5/a5cc2925ca8258af241be7e5b0381edf30266302
deleted file mode 100644
index e69de29..0000000

From 06db2f6b99bec5afd91fa81359f360c612b8bd27 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Sun, 15 May 2022 23:52:57 +0530
Subject: [PATCH 08/19] add Anghel Leonard's github profile link

---
 .../issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec    | 0
 README.md                                                      | 3 ++-
 2 files changed, 2 insertions(+), 1 deletion(-)
 delete mode 100644 .idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec

diff --git a/.idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec b/.idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec
deleted file mode 100644
index e69de29..0000000
diff --git a/README.md b/README.md
index 3bd4ca1..5779e48 100644
--- a/README.md
+++ b/README.md
@@ -28,7 +28,8 @@ Write a program that counts duplicate characters from a given `String`.
 
 ---
 > Question taken from the book
-> ["Java Coding Problems"](https://www.packtpub.com/product/java-coding-problems/9781789801415) by Anghel Leonard.  
+> ["Java Coding Problems"](https://www.packtpub.com/product/java-coding-problems/9781789801415) by
+> [Anghel Leonard](https://github.com/AnghelLeonard).  
 > Formatted and uploaded by [dbc2201](https://github.com/dbc2201)
 
 ---

From 8ecf528cb98b4eb81f0a5f2bcf8f66f864f86100 Mon Sep 17 00:00:00 2001
From: Divyansh Bhardwaj <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 00:46:12 +0530
Subject: [PATCH 09/19] Create LICENSE

---
 LICENSE | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 LICENSE

diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..742effe
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2022 Divyansh Bhardwaj
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

From 237485f9bdba4a7277b3274b782f1146aea1021a Mon Sep 17 00:00:00 2001
From: Divyansh Bhardwaj <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 00:55:00 +0530
Subject: [PATCH 10/19] Create maven.yml

---
 .github/workflows/maven.yml | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 .github/workflows/maven.yml

diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
new file mode 100644
index 0000000..9f49c41
--- /dev/null
+++ b/.github/workflows/maven.yml
@@ -0,0 +1,29 @@
+# This workflow will build a Java project with Maven, and cache/restore any dependencies to improve the workflow execution time
+# For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-maven
+
+name: Java CI with Maven
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up JDK 18
+      uses: actions/setup-java@v3
+      with:
+        java-version: '11'
+        distribution: 'corretto'
+        cache: maven
+    - name: Build with Maven
+      run: mvn -B package --file pom.xml
+    - name: Test with Maven
+      run: mvn test
+      

From 9634f3d168ae40701ba9155dd4e9761d2ef17026 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 01:04:43 +0530
Subject: [PATCH 11/19] change maven target version to 11

---
 .gitignore                                    |  4 +-
 .idea/misc.xml                                |  2 +-
 .../442292b8a7efeabbe4cc176709b833b1792140ec  |  0
 .../8a6dae537be9f47878c6964c6ee40cab0ca75e28  |  0
 .idea/sonarlint/issuestore/index.pb           |  5 --
 .idea/workspace.xml                           | 46 +++++++++++++------
 pom.xml                                       |  4 +-
 .../dbc/DuplicateCharactersCounterTest.java   |  3 +-
 8 files changed, 39 insertions(+), 25 deletions(-)
 delete mode 100644 .idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec
 delete mode 100644 .idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28

diff --git a/.gitignore b/.gitignore
index 9f91b2d..e9ddf70 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,7 @@ target/
 !**/src/test/**/target/
 
 ### IntelliJ IDEA ###
+.idea/
 .idea/modules.xml
 .idea/jarRepositories.xml
 .idea/compiler.xml
@@ -38,4 +39,5 @@ build/
 .DS_Store
 
 ### SonarLint ###
-.idea/sonarlint/
\ No newline at end of file
+
+!/.idea/sonarlint/
diff --git a/.idea/misc.xml b/.idea/misc.xml
index 4258c62..0bc224b 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -8,7 +8,7 @@
       </list>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_18" default="true" project-jdk-name="18" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="18" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec b/.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec
deleted file mode 100644
index e69de29..0000000
diff --git a/.idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28 b/.idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28
deleted file mode 100644
index e69de29..0000000
diff --git a/.idea/sonarlint/issuestore/index.pb b/.idea/sonarlint/issuestore/index.pb
index ff5edbe..e69de29 100644
--- a/.idea/sonarlint/issuestore/index.pb
+++ b/.idea/sonarlint/issuestore/index.pb
@@ -1,5 +0,0 @@
-
-w
-G.idea/sonarlint/issuestore/e/d/ed67eb178d523a4b3f117dcbe0eda5196367ceec,8\a\8a6dae537be9f47878c6964c6ee40cab0ca75e28
-w
-G.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec,8\6\863e0292fd7e9b3e74dafd6cc01f73ba76346482
\ No newline at end of file
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 33f4569..d2f558c 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,10 +4,15 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add proper test names">
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="change maven target version to 11">
+      <change beforePath="$PROJECT_DIR$/.gitignore" beforeDir="false" afterPath="$PROJECT_DIR$/.gitignore" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/misc.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/misc.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec" beforeDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28" beforeDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/pom.xml" beforeDir="false" afterPath="$PROJECT_DIR$/pom.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -43,18 +48,29 @@
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent">{
-  &quot;keyToString&quot;: {
-    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
-    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
-    &quot;SONARLINT_PRECOMMIT_ANALYSIS&quot;: &quot;true&quot;,
-    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary&quot;: &quot;JUnit5&quot;,
-    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5&quot;: &quot;&quot;,
-    &quot;full.screen.before.presentation.mode&quot;: &quot;false&quot;,
-    &quot;last_opened_file_path&quot;: &quot;C:/Users/divya/Exercism/java/need-for-speed&quot;,
-    &quot;settings.editor.selected.configurable&quot;: &quot;reference.settingsdialog.IDE.editor.colors.Color Scheme Font&quot;
+  <component name="PropertiesComponent"><![CDATA[{
+  "keyToString": {
+    "RunOnceActivity.OpenProjectViewOnStart": "true",
+    "RunOnceActivity.ShowReadmeOnStart": "true",
+    "SONARLINT_PRECOMMIT_ANALYSIS": "true",
+    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary": "JUnit5",
+    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5": "",
+    "full.screen.before.presentation.mode": "false",
+    "last_opened_file_path": "C:/Users/divya/Exercism/java/need-for-speed",
+    "project.structure.last.edited": "Project",
+    "project.structure.proportion": "0.15",
+    "project.structure.side.proportion": "0.0",
+    "settings.editor.selected.configurable": "preferences.pluginManager"
+  },
+  "keyToStringList": {
+    "DatabaseDriversLRU": [
+      "mysql"
+    ],
+    "com.intellij.ide.scratch.ScratchImplUtil$2/New Scratch File": [
+      "Markdown"
+    ]
   }
-}</component>
+}]]></component>
   <component name="RecentsManager">
     <key name="CreateTestDialog.Recents.Supers">
       <recent name="" />
@@ -157,6 +173,7 @@
       <workItem from="1652622259082" duration="160000" />
       <workItem from="1652631231540" duration="1640000" />
       <workItem from="1652638374278" duration="312000" />
+      <workItem from="1652815591071" duration="292000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -310,7 +327,8 @@
     <MESSAGE value="make test file read-only" />
     <MESSAGE value="use the @NullSource and @EmptySource annotations for tests" />
     <MESSAGE value="add proper test names" />
-    <option name="LAST_COMMIT_MESSAGE" value="add proper test names" />
+    <MESSAGE value="change maven target version to 11" />
+    <option name="LAST_COMMIT_MESSAGE" value="change maven target version to 11" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />
diff --git a/pom.xml b/pom.xml
index 1149d30..513edc9 100644
--- a/pom.xml
+++ b/pom.xml
@@ -17,8 +17,8 @@
     </dependencies>
 
     <properties>
-        <maven.compiler.source>18</maven.compiler.source>
-        <maven.compiler.target>18</maven.compiler.target>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
     </properties>
 
 </project>
\ No newline at end of file
diff --git a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
index 1489a67..537d1df 100644
--- a/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
+++ b/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java
@@ -26,8 +26,7 @@ void shouldReturnMapOfCorrectSize(String input) {
         // Act
         var characterIntegerMap = counter.countDuplicateCharacters(input);
         // Assert
-        assertEquals(input.length(), characterIntegerMap.size(),
-                "the map should have the same size as the input string");
+        assertEquals(input.length(), characterIntegerMap.size(), "the map should have the same size as the input string");
     }
 
     @Test

From cb3ab1b537f53d4450d7a0efe266cfe7aaf6d440 Mon Sep 17 00:00:00 2001
From: Divyansh Bhardwaj <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 01:36:04 +0530
Subject: [PATCH 12/19] Update maven.yml

---
 .github/workflows/maven.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index 9f49c41..7084438 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -16,7 +16,7 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up JDK 18
+    - name: Set up JDK 11 Amazon Corretto
       uses: actions/setup-java@v3
       with:
         java-version: '11'
@@ -24,6 +24,6 @@ jobs:
         cache: maven
     - name: Build with Maven
       run: mvn -B package --file pom.xml
-    - name: Test with Maven
-      run: mvn test
+    - name: Publish Test Report
+      uses: mikepenz/action-junit-report@v3
       

From f1515bee291fe220d44e03d92438c76e46940e6c Mon Sep 17 00:00:00 2001
From: Divyansh Bhardwaj <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 01:40:09 +0530
Subject: [PATCH 13/19] Update maven.yml

---
 .github/workflows/maven.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index 7084438..d96d843 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -24,6 +24,6 @@ jobs:
         cache: maven
     - name: Build with Maven
       run: mvn -B package --file pom.xml
-    - name: Publish Test Report
-      uses: mikepenz/action-junit-report@v3
+    - name: Test with Maven
+      run: mvn -B test --file pom.xml
       

From 66f624261ba3beb54cdfdf9d55dd1b6847e86651 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 01:56:14 +0530
Subject: [PATCH 14/19] add maven plugins to run junit5 test with maven

---
 .idea/workspace.xml | 17 +++++++++--------
 pom.xml             | 23 +++++++++++++++++++++++
 2 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index d2f558c..8dab1cc 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -5,14 +5,8 @@
   </component>
   <component name="ChangeListManager">
     <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="change maven target version to 11">
-      <change beforePath="$PROJECT_DIR$/.gitignore" beforeDir="false" afterPath="$PROJECT_DIR$/.gitignore" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/.idea/misc.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/misc.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/4/4/442292b8a7efeabbe4cc176709b833b1792140ec" beforeDir="false" />
-      <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/8/a/8a6dae537be9f47878c6964c6ee40cab0ca75e28" beforeDir="false" />
-      <change beforePath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/sonarlint/issuestore/index.pb" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/pom.xml" beforeDir="false" afterPath="$PROJECT_DIR$/pom.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/test/java/io/github/dbc/DuplicateCharactersCounterTest.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -173,7 +167,7 @@
       <workItem from="1652622259082" duration="160000" />
       <workItem from="1652631231540" duration="1640000" />
       <workItem from="1652638374278" duration="312000" />
-      <workItem from="1652815591071" duration="292000" />
+      <workItem from="1652815591071" duration="1996000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -294,7 +288,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652633662838</updated>
     </task>
-    <option name="localTasksCounter" value="18" />
+    <task id="LOCAL-00018" summary="change maven target version to 11">
+      <created>1652816083393</created>
+      <option name="number" value="00018" />
+      <option name="presentableId" value="LOCAL-00018" />
+      <option name="project" value="LOCAL" />
+      <updated>1652816083393</updated>
+    </task>
+    <option name="localTasksCounter" value="19" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
diff --git a/pom.xml b/pom.xml
index 513edc9..629d57c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -17,8 +17,31 @@
     </dependencies>
 
     <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.compiler.source>11</maven.compiler.source>
         <maven.compiler.target>11</maven.compiler.target>
     </properties>
 
+    <build>
+        <pluginManagement>
+            <plugins>
+                <plugin>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-compiler-plugin</artifactId>
+                    <version>3.9.0</version>
+                    <configuration>
+                        <source>11</source>
+                        <target>11</target>
+                    </configuration>
+                </plugin>
+                <plugin>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-surefire-plugin</artifactId>
+                    <version>2.22.2</version>
+                </plugin>
+
+            </plugins>
+        </pluginManagement>
+    </build>
+
 </project>
\ No newline at end of file

From f93d348c466563f02e799853138dee46f93d8aac Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 02:01:12 +0530
Subject: [PATCH 15/19] add a badge, change name for the workflow

---
 .github/workflows/maven.yml | 24 ++++++++++++------------
 .idea/workspace.xml         | 19 +++++++++++++------
 README.md                   |  1 +
 3 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index d96d843..2f44ced 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -1,7 +1,7 @@
 # This workflow will build a Java project with Maven, and cache/restore any dependencies to improve the workflow execution time
 # For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-maven
 
-name: Java CI with Maven
+name: Test Case Report
 
 on:
   push:
@@ -15,15 +15,15 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
-    - name: Set up JDK 11 Amazon Corretto
-      uses: actions/setup-java@v3
-      with:
-        java-version: '11'
-        distribution: 'corretto'
-        cache: maven
-    - name: Build with Maven
-      run: mvn -B package --file pom.xml
-    - name: Test with Maven
-      run: mvn -B test --file pom.xml
+      - uses: actions/checkout@v3
+      - name: Set up JDK 11 Amazon Corretto
+        uses: actions/setup-java@v3
+        with:
+          java-version: '11'
+          distribution: 'corretto'
+          cache: maven
+      - name: Build with Maven
+        run: mvn -B package --file pom.xml
+      - name: Test with Maven
+        run: mvn -B test --file pom.xml
       
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 8dab1cc..186519c 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,9 +4,8 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="change maven target version to 11">
-      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/pom.xml" beforeDir="false" afterPath="$PROJECT_DIR$/pom.xml" afterDir="false" />
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add maven plugins to run junit5 test with maven">
+      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -167,7 +166,7 @@
       <workItem from="1652622259082" duration="160000" />
       <workItem from="1652631231540" duration="1640000" />
       <workItem from="1652638374278" duration="312000" />
-      <workItem from="1652815591071" duration="1996000" />
+      <workItem from="1652815591071" duration="2395000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -295,7 +294,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652816083393</updated>
     </task>
-    <option name="localTasksCounter" value="19" />
+    <task id="LOCAL-00019" summary="add maven plugins to run junit5 test with maven">
+      <created>1652819174296</created>
+      <option name="number" value="00019" />
+      <option name="presentableId" value="LOCAL-00019" />
+      <option name="project" value="LOCAL" />
+      <updated>1652819174296</updated>
+    </task>
+    <option name="localTasksCounter" value="20" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -329,7 +335,8 @@
     <MESSAGE value="use the @NullSource and @EmptySource annotations for tests" />
     <MESSAGE value="add proper test names" />
     <MESSAGE value="change maven target version to 11" />
-    <option name="LAST_COMMIT_MESSAGE" value="change maven target version to 11" />
+    <MESSAGE value="add maven plugins to run junit5 test with maven" />
+    <option name="LAST_COMMIT_MESSAGE" value="add maven plugins to run junit5 test with maven" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />
diff --git a/README.md b/README.md
index 5779e48..e6e5df0 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,4 @@
+[![Test Case Report](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml/badge.svg?event=push)](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml)
 # Java Coding Problems
 
 ## Chapter 1: Strings, Numbers, and Math

From d8cf7a8c0b94889a1d5dd766e8d6799164ad88df Mon Sep 17 00:00:00 2001
From: Divyansh Bhardwaj <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 17:11:19 +0530
Subject: [PATCH 16/19] Create super-linter.yml

---
 .github/workflows/super-linter.yml | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 .github/workflows/super-linter.yml

diff --git a/.github/workflows/super-linter.yml b/.github/workflows/super-linter.yml
new file mode 100644
index 0000000..bd14a83
--- /dev/null
+++ b/.github/workflows/super-linter.yml
@@ -0,0 +1,29 @@
+# This workflow executes several linters on changed files based on languages used in your code base whenever
+# you push a code or open a pull request.
+#
+# You can adjust the behavior by modifying this file.
+# For more information, see:
+# https://github.com/github/super-linter
+name: Lint Code Base
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+jobs:
+  run-lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+        with:
+          # Full git history is needed to get a proper list of changed files within `super-linter`
+          fetch-depth: 0
+
+      - name: Lint Code Base
+        uses: github/super-linter@v4
+        env:
+          VALIDATE_ALL_CODEBASE: false
+          DEFAULT_BRANCH: main
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

From 65562fa61967e2efd7480890fed02dd043e2172e Mon Sep 17 00:00:00 2001
From: Divyansh Bhardwaj <divyanshb22@gmail.com>
Date: Wed, 18 May 2022 17:14:32 +0530
Subject: [PATCH 17/19] add badge for lint checks

---
 README.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index e6e5df0..0b7ed94 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-[![Test Case Report](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml/badge.svg?event=push)](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml)
+[![Test Case Report](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml/badge.svg?event=push)](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml) [![Lint Code Base](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/super-linter.yml/badge.svg)](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/super-linter.yml)
 # Java Coding Problems
 
 ## Chapter 1: Strings, Numbers, and Math
@@ -38,4 +38,4 @@ Write a program that counts duplicate characters from a given `String`.
 **Suggested Reading:**
 
 1. [HashMap (Java SE 18 & JDK 18)](https://docs.oracle.com/en/java/javase/18/docs/api/java.base/java/util/HashMap.html)
-2. [Managing the Content of a Map (dev.java)](https://dev.java/learn/managing-the-content-of-a-map/)
\ No newline at end of file
+2. [Managing the Content of a Map (dev.java)](https://dev.java/learn/managing-the-content-of-a-map/)

From d8ff4bd1886f4ee3a4d8fc7818dda4d5cdef8da2 Mon Sep 17 00:00:00 2001
From: Divyansh Bhardwaj <divyanshb22@gmail.com>
Date: Thu, 19 May 2022 01:58:12 +0530
Subject: [PATCH 18/19] Update README.md

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 0b7ed94..454aed7 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-[![Test Case Report](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml/badge.svg?event=push)](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml) [![Lint Code Base](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/super-linter.yml/badge.svg)](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/super-linter.yml)
+[![Test Case Report](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml/badge.svg?event=push)](https://github.com/dbc2201/JavaCodingProblem1/actions/workflows/maven.yml) 
 # Java Coding Problems
 
 ## Chapter 1: Strings, Numbers, and Math

From 3a84ff3aac9bbeac44391f52a2ec8fde8dcdcf20 Mon Sep 17 00:00:00 2001
From: dbc2201 <divyanshb22@gmail.com>
Date: Thu, 26 May 2022 12:13:04 +0530
Subject: [PATCH 19/19] add throws statement in javadoc

---
 .idea/workspace.xml                           | 56 ++++++++++---------
 .../dbc/DuplicateCharactersCounter.java       |  1 +
 2 files changed, 32 insertions(+), 25 deletions(-)

diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 186519c..4e9c26f 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,9 +4,7 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add maven plugins to run junit5 test with maven">
-      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
-    </list>
+    <list default="true" id="b3bac6d6-f8b1-474b-a5e1-72bf67a3867c" name="Changes" comment="add a badge, change name for the workflow" />
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -41,29 +39,29 @@
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent"><![CDATA[{
-  "keyToString": {
-    "RunOnceActivity.OpenProjectViewOnStart": "true",
-    "RunOnceActivity.ShowReadmeOnStart": "true",
-    "SONARLINT_PRECOMMIT_ANALYSIS": "true",
-    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary": "JUnit5",
-    "com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5": "",
-    "full.screen.before.presentation.mode": "false",
-    "last_opened_file_path": "C:/Users/divya/Exercism/java/need-for-speed",
-    "project.structure.last.edited": "Project",
-    "project.structure.proportion": "0.15",
-    "project.structure.side.proportion": "0.0",
-    "settings.editor.selected.configurable": "preferences.pluginManager"
+  <component name="PropertiesComponent">{
+  &quot;keyToString&quot;: {
+    &quot;RunOnceActivity.OpenProjectViewOnStart&quot;: &quot;true&quot;,
+    &quot;RunOnceActivity.ShowReadmeOnStart&quot;: &quot;true&quot;,
+    &quot;SONARLINT_PRECOMMIT_ANALYSIS&quot;: &quot;true&quot;,
+    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary&quot;: &quot;JUnit5&quot;,
+    &quot;com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit5&quot;: &quot;&quot;,
+    &quot;full.screen.before.presentation.mode&quot;: &quot;false&quot;,
+    &quot;last_opened_file_path&quot;: &quot;C:/Users/divya/Exercism/java/need-for-speed&quot;,
+    &quot;project.structure.last.edited&quot;: &quot;Project&quot;,
+    &quot;project.structure.proportion&quot;: &quot;0.15&quot;,
+    &quot;project.structure.side.proportion&quot;: &quot;0.0&quot;,
+    &quot;settings.editor.selected.configurable&quot;: &quot;preferences.pluginManager&quot;
   },
-  "keyToStringList": {
-    "DatabaseDriversLRU": [
-      "mysql"
+  &quot;keyToStringList&quot;: {
+    &quot;DatabaseDriversLRU&quot;: [
+      &quot;mysql&quot;
     ],
-    "com.intellij.ide.scratch.ScratchImplUtil$2/New Scratch File": [
-      "Markdown"
+    &quot;com.intellij.ide.scratch.ScratchImplUtil$2/New Scratch File&quot;: [
+      &quot;Markdown&quot;
     ]
   }
-}]]></component>
+}</component>
   <component name="RecentsManager">
     <key name="CreateTestDialog.Recents.Supers">
       <recent name="" />
@@ -166,7 +164,7 @@
       <workItem from="1652622259082" duration="160000" />
       <workItem from="1652631231540" duration="1640000" />
       <workItem from="1652638374278" duration="312000" />
-      <workItem from="1652815591071" duration="2395000" />
+      <workItem from="1652815591071" duration="2935000" />
     </task>
     <task id="LOCAL-00001" summary="initial commit">
       <created>1652464516513</created>
@@ -301,7 +299,14 @@
       <option name="project" value="LOCAL" />
       <updated>1652819174296</updated>
     </task>
-    <option name="localTasksCounter" value="20" />
+    <task id="LOCAL-00020" summary="add a badge, change name for the workflow">
+      <created>1652819472258</created>
+      <option name="number" value="00020" />
+      <option name="presentableId" value="LOCAL-00020" />
+      <option name="project" value="LOCAL" />
+      <updated>1652819472258</updated>
+    </task>
+    <option name="localTasksCounter" value="21" />
     <servers />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
@@ -336,7 +341,8 @@
     <MESSAGE value="add proper test names" />
     <MESSAGE value="change maven target version to 11" />
     <MESSAGE value="add maven plugins to run junit5 test with maven" />
-    <option name="LAST_COMMIT_MESSAGE" value="add maven plugins to run junit5 test with maven" />
+    <MESSAGE value="add a badge, change name for the workflow" />
+    <option name="LAST_COMMIT_MESSAGE" value="add a badge, change name for the workflow" />
     <option name="OPTIMIZE_IMPORTS_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REFORMAT_BEFORE_PROJECT_COMMIT" value="true" />
     <option name="REARRANGE_BEFORE_PROJECT_COMMIT" value="true" />
diff --git a/src/main/java/io/github/dbc/DuplicateCharactersCounter.java b/src/main/java/io/github/dbc/DuplicateCharactersCounter.java
index 9020649..49cee5a 100644
--- a/src/main/java/io/github/dbc/DuplicateCharactersCounter.java
+++ b/src/main/java/io/github/dbc/DuplicateCharactersCounter.java
@@ -8,6 +8,7 @@ public class DuplicateCharactersCounter {
      *
      * @param string String to count duplicate characters.
      * @return Map with characters and their count.
+     * @throws IllegalArgumentException if the input is null or empty.
      */
     public Map<Character, Integer> countDuplicateCharacters(String string) {
         return Map.of();