Java / Design Patterns

In Java singleton, how do you prevent creating instance using reflection?

Create a constructor and throw InstantiationError when the private singleton instance reference is not null.

private Singleton() {
    if( Singleton.singleton != null ) {
        throw new InstantiationError( "Creating of this object is not allowed." );
    }
}

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Java / Design Patterns

In Java singleton, how do you prevent creating instance using reflection?

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