How is it possible for two String objects with identical values not to be equal under the == operator?

Java Interview Questions and Answers (part 2)

(Continued from previous question...)

308. How is it possible for two String objects with identical values not to be equal under the == operator?

The == operator compares two objects to determine if they are the same object in memory. It is possible for two String objects to have the same value, but located indifferent areas of memory.

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Other Interview Questions

• Which java.util classes and interfaces support event handling?
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• What are wrapper classes?
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• What is the immediate superclass of Menu?
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• What is the argument type of a program's main() method?
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• What is the Locale class?
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• What must a class do to implement an interface?
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• What is the advantage of the event-delegation model over the earlier event-inheritance model?
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• What is an abstract method?
• How are Java source code files named?
• What is the relationship between the Canvas class and the Graphics class?
• What are the high-level thread states?
• What value does read() return when it has reached the end of a file?
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• What is the difference between the String and StringBuffer classes?
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• What is an object's lock and which objects have locks?
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• What advantage do Java's layout managers provide over traditional windowing systems?
• What is the Collection interface?
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• What is casting?
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• Why are the methods of the Math class static?
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