Java Array Equal equals(Object array1, Object array2)

Description

Determines if the given two arrays are equal, as determined by comparing their contents for equality.

License

Apache License

Parameter

Parameter	Description
array1	an array
array2	another array

Exception

Parameter	Description
IllegalArgumentException	if array1 is not actually an array

Return

true if array2 is an array of the same type as array1 and has equal elements

Declaration

public static boolean equals(Object array1, Object array2) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

import java.util.Arrays;

public class Main {
    /**// ww w.j  a  v a2  s. c  om
     * Determines if the given two arrays are equal, as determined by comparing their contents for
     * equality. This provides a convenience above and beyond similar methods in {@link Arrays}
     * because it accepts any array type, including primitive array types.
     *
     * @param array1 an array
     * @param array2 another array
     * @return true if {@code array2} is an array of the same type as {@code array1} and has equal
     *    elements
     * @throws IllegalArgumentException if {@code array1} is not actually an array
     * 
     * @see Arrays#equals(Object[], Object[])
     */
    public static boolean equals(Object array1, Object array2) {
        Class<?> arrayType = array1.getClass();
        if (!arrayType.isArray()) {
            throw new IllegalArgumentException("specified object is not an array");
        }
        Class<?> componentType = arrayType.getComponentType();
        if (componentType.isPrimitive()) {
            if (componentType == boolean.class) {
                return array2 instanceof boolean[] && Arrays.equals((boolean[]) array1, (boolean[]) array2);
            } else if (componentType == byte.class) {
                return array2 instanceof byte[] && Arrays.equals((byte[]) array1, (byte[]) array2);
            } else if (componentType == char.class) {
                return array2 instanceof char[] && Arrays.equals((char[]) array1, (char[]) array2);
            } else if (componentType == short.class) {
                return array2 instanceof short[] && Arrays.equals((short[]) array1, (short[]) array2);
            } else if (componentType == int.class) {
                return array2 instanceof int[] && Arrays.equals((int[]) array1, (int[]) array2);
            } else if (componentType == long.class) {
                return array2 instanceof long[] && Arrays.equals((long[]) array1, (long[]) array2);
            } else if (componentType == float.class) {
                return array2 instanceof float[] && Arrays.equals((float[]) array1, (float[]) array2);
            } else if (componentType == double.class) {
                return array2 instanceof double[] && Arrays.equals((double[]) array1, (double[]) array2);
            } else {
                throw new AssertionError("Unrecognized primitive type: " + componentType);
            }
        } else {
            return array2 instanceof Object[] && Arrays.equals((Object[]) array1, (Object[]) array2);
        }
    }
}

Related

1. equals(long[] a, long[] a2)
2. equals(Map a, Map b)
3. equals(Map map1, Map map2)
4. equals(Object array1, Object array2)
5. equals(Object array1, Object array2)
6. equals(Object[] objs1, Object[] objs2)
7. equals(String[] fullSet, String[] subSet)
8. equals(T[] array1, T[] array2)
9. equals3(double[][][] arr1, double[][][] arr2)