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Arrays do not override the Object.equals() method; rather, the implementation of the equals() method compares array references rather than their contents. To compare the contents of two arrays, use the two-argument Arrays.equals() method instead. When intentionally testing reference equality, use the reference equality operators, == and !=. Inappropriate use of the equals() method can lead to unexpected results. Consequently, programs must reserve use of the array equality operators == and != for testing whether two array references specifically refer to the same array object, and are required to use the two-argument Arrays.equals() method for all other cases.

This rule is a specialization of EXP01-J. Do not confuse abstract object equality with reference equality.

Noncompliant Code Example

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