What is the difference between == and .equals() in Java?

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Accepted Answer

The two operators look similar but compare different things. == operator — compares references (memory addresses) for objects, and values for primitives. Two new String("a") objects return false . .equals() method — compares logical content . Default in Object is reference equality, but classes like String , Integer , and collections override it for value equality. Rule — use == for primitives and reference identity; use .equals() for object content. Always override hashCode() when overriding equals() . The Integer caching gotcha (-128 to 127) is a classic interview question. Always mention the equals/hashCode contract. The String pool behavior explains why == sometimes works for Strings (misleading beginners).