Initial upload new files

joeyajames · web-flow · commit 8744c229644b · 2023-04-16T18:04:41.000-07:00
diff --git a/EscapeNestedLoops.java b/EscapeNestedLoops.java
@@ -0,0 +1,26 @@
+// Java - How to Break out of Nested For Loops
+
+class EscapeNestedLoops {
+	public static void main(String[] args) {
+
+		for(int x=0; x<8; x++) {
+			for(int y=1; y<4; y++) {
+				System.out.println(x + " " + y + " " + x*y);
+				if(x * y > 5)
+					break;
+			}
+		}
+
+		System.out.println(" ");
+		
+		xLoop:
+		for(int x=0; x<8; x++) {
+			for(int y=1; y<4; y++) {
+				System.out.println(x + " " + y + " " + x*y);
+				if(x * y > 5)
+					break xLoop;
+			}
+		}
+
+	}
+}
diff --git a/ListToArray.java b/ListToArray.java
@@ -0,0 +1,45 @@
+// Java: convert ArrayList<String> to String[]
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.*;
+
+class ListToArray {
+	public static void main(String[] args) {
+		// create Array
+		String[] array = {"Bugatti", "Ferarri", "Lamborghini", "Rolls Royce"};
+		
+		// 3 ways to print Array
+		System.out.println(Arrays.toString(array));
+
+		for(String s : array) {
+			System.out.print(s + ", ");
+		}
+		System.out.println();
+
+		Stream.of(array) 
+			.forEach(System.out::println);
+		
+		// 2 ways to convert Array to ArrayList
+		List<String> arrayList = new ArrayList<>(Arrays.asList(array));
+		System.out.println("arrayList: " + arrayList);
+		
+		List<String> arrayList2 = new ArrayList<>(List.of(array));
+		System.out.println("arrayList2: " + arrayList2);
+		
+		// convert ArrayList to Array
+		String[] array2 = arrayList.toArray(new String[0]);
+
+		// print Array
+		Stream.of(array2) 
+			.forEach(System.out::println);
+
+	}
+}
+
+
+
+
+
+
+
diff --git a/SplitString.java b/SplitString.java
@@ -0,0 +1,35 @@
+// Java: Split a String at char
+import java.util.Arrays;
+
+class SplitString {
+	
+	public static void main(String[] args) {
+		String s = "My dog ate my homework; Can I turn it in tomorrow?";
+
+		String[] ss = s.split(" ");
+		System.out.println(Arrays.toString(ss));
+
+		ss = s.split(";");
+		System.out.println(Arrays.toString(ss));
+
+		// you must escape special chars because the split parameter is a regex
+		// special chars include \ . + ^ $ | ? * ( ) [ {
+		String t = "54.25-128.17";
+		String[] tt = t.split("\\.");
+		System.out.println(Arrays.toString(tt));
+
+		// include multiple split chars inside brackets
+		tt = t.split("[.-]");
+		System.out.println(Arrays.toString(tt));
+
+	}
+}
+
+
+
+
+
+
+
+
+
diff --git a/StringToInt.java b/StringToInt.java
@@ -0,0 +1,26 @@
+// Java - Convert String to an Int
+
+class StringToInt {
+	public static void main(String[] args) {
+		String s = "222";
+		int i;
+		Integer integer;
+		
+		// returns an int
+		i = Integer.parseInt(s); 
+		System.out.println(i + 1);
+
+		// returns an Integer
+		integer = Integer.valueOf(s); 
+		System.out.println(integer + 2);
+
+		// Best Practice: safely returns an Integer
+		try {
+			integer = Integer.valueOf(s); 
+		} catch (NumberFormatException e) {
+			integer = 0;
+		}
+		System.out.println(integer + 3);
+	}
+
+}
