Why Does \'==\' Fail to Compare Strings Correctly in Java?

String Comparison with ==

In Java, comparing strings using "==" may return unexpected results. Contrary to expectation, applying "==" to two string variables may result in "false" even if they appear identical.

Consider the following code:

String parts[] = {"231", "CA-California", "Sacramento-155328", "aleee", "Customer Service Clerk", "Alegra Keith.doc.txt"};

System.out.println("231" == parts[0]); // False

Explanation:

The "==" operator in Java tests whether two objects refer to the same memory location. In the above example, parts[0] and "231" are two separate objects in memory, even though they both hold the same value ("231"). Hence, "231" == parts[0] evaluates to false.

Solution:

To compare the values of strings in Java, use the equals method. The equals method, inherited from Object, returns true if two strings have the same value.

System.out.println("231".equals(parts[0])); // True

Best Practice:

In Java, always use equals for comparing objects, including strings. This practice ensures that you are comparing the values of the objects, not their memory references.

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