Update AbsoluteMax (TheAlgorithms#4140)

realDuYuanChao · web-flow · commit d1601560032b · 2023-04-03T22:39:17.000+08:00
diff --git a/src/main/java/com/thealgorithms/maths/AbsoluteMax.java b/src/main/java/com/thealgorithms/maths/AbsoluteMax.java
@@ -1,30 +1,24 @@
 package com.thealgorithms.maths;
 
-import java.util.Arrays;
-
 public class AbsoluteMax {
 
     /**
-     * Compares the numbers given as arguments to get the absolute max value.
+     * Finds the absolute maximum value among the given numbers.
      *
-     * @param numbers The numbers to compare
-     * @return The absolute max value
+     * @param numbers The numbers to compare.
+     * @return The absolute maximum value.
+     * @throws IllegalArgumentException If the input array is empty or null.
      */
     public static int getMaxValue(int... numbers) {
-        if (numbers.length == 0) {
-            throw new IllegalArgumentException("Numbers array cannot be empty");
+        if (numbers == null || numbers.length == 0) {
+            throw new IllegalArgumentException("Numbers array cannot be empty or null");
         }
-
-        var absMaxWrapper = new Object() {
-            int value = numbers[0];
-        };
-
-        Arrays
-            .stream(numbers)
-            .skip(1)
-            .filter(number -> Math.abs(number) > Math.abs(absMaxWrapper.value))
-            .forEach(number -> absMaxWrapper.value = number);
-
-        return absMaxWrapper.value;
+        int absMax = numbers[0];
+        for (int i = 1; i < numbers.length; i++) {
+            if (Math.abs(numbers[i]) > Math.abs(absMax)) {
+                absMax = numbers[i];
+            }
+        }
+        return absMax;
     }
 }
diff --git a/src/test/java/com/thealgorithms/maths/AbsoluteMaxTest.java b/src/test/java/com/thealgorithms/maths/AbsoluteMaxTest.java
@@ -10,15 +10,12 @@ public class AbsoluteMaxTest {
     @Test
     void testGetMaxValue() {
         assertEquals(16, AbsoluteMax.getMaxValue(-2, 0, 16));
-        assertEquals(-10, AbsoluteMax.getMaxValue(3, -10, -2));
+        assertEquals(-22, AbsoluteMax.getMaxValue(-3, -10, -22));
+        assertEquals(-888, AbsoluteMax.getMaxValue(-888));
     }
 
     @Test
     void testGetMaxValueWithNoArguments() {
-        Exception exception = assertThrows(
-            IllegalArgumentException.class,
-            () -> AbsoluteMax.getMaxValue()
-        );
-        assertEquals("Numbers array cannot be empty", exception.getMessage());
+        assertThrows(IllegalArgumentException.class, AbsoluteMax::getMaxValue);
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -10,15 +10,12 @@ public class AbsoluteMaxTest {`
`10`	`10`	`@Test`
`11`	`11`	`void testGetMaxValue() {`
`12`	`12`	`assertEquals(16, AbsoluteMax.getMaxValue(-2, 0, 16));`
`13`		`- assertEquals(-10, AbsoluteMax.getMaxValue(3, -10, -2));`
	`13`	`+ assertEquals(-22, AbsoluteMax.getMaxValue(-3, -10, -22));`
	`14`	`+ assertEquals(-888, AbsoluteMax.getMaxValue(-888));`
`14`	`15`	`}`
`15`	`16`
`16`	`17`	`@Test`
`17`	`18`	`void testGetMaxValueWithNoArguments() {`
`18`		`- Exception exception = assertThrows(`
`19`		`- IllegalArgumentException.class,`
`20`		`- () -> AbsoluteMax.getMaxValue()`
`21`		`- );`
`22`		`- assertEquals("Numbers array cannot be empty", exception.getMessage());`
	`19`	`+ assertThrows(IllegalArgumentException.class, AbsoluteMax::getMaxValue);`
`23`	`20`	`}`
`24`	`21`	`}`