How to make a class or a bean serializable?

Java Interview Questions and Answers (part 3)

(Continued from previous question...)

436. How to make a class or a bean serializable?

By implementing either the java.io.Serializable interface, or the java.io.Externalizable interface. As long as one class in a class's inheritance hierarchy implements Serializable or Externalizable, that class is serializable.

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Other Interview Questions

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• What does it mean that a class or member is final?
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• What is the package?
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• Can main() method be overloaded?
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• Explain the new Features of JDBC 2.0 Core API?
• Explain garbage collection?
• How you can force the garbage collection?
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• Explain the Polymorphism principle.
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• What is Data Access Object pattern?
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• When and How is an object considered as Garbage by a GC?
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• When to Use the Throughput Collector?
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• What is a Concurrent Low Pause Collector?
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• 472. State the significance of public, private, protected, default modifiers both singly and in combination and state the effect of package relationships on declared items qualified by these modifiers.
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• What is static in java?
• What is final?
• What if the main method is declared as private?
• What if the static modifier is removed from the signature of the main method?
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• What is the first argument of the String array in main method?
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• How can one prove that the array is not null but empty using one line of code?
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