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Equality operators

Equality operators compare two values for equality or inequality and return a boolean result.

OperatorDescriptionExample
==Equal toa == b
!=Not equal toa != b

With primitives: Compare actual values.

int x = 5, y = 5;
System.out.println(x == y); // true

With objects: == compares references (whether they point to the same object), not content.

String s1 = "hello";
String s2 = "hello";
String s3 = new String("hello");


System.out.println(s1 == s2); // true (same string literal pool)
System.out.println(s1 == s3); // false (different objects)
System.out.println(s1.equals(s3)); // true (content comparison)

Important: Always use .equals() for object content comparison, unless you specifically want reference equality.

With null: You can check for null using == or !=.

String str = null;
if (str == null) {
    System.out.println("Null reference");
}