32 lines
941 B
Java
32 lines
941 B
Java
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Writing a Thread-Safe Singleton
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public class JGKSingleton
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{
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/* Here is the instance of the Singleton */
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private static JGKSingleton instance_;
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/* Need the following object to synchronize */
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/* a block */
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private static Object syncObject_;
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/* Prevent direct access to the constructor*/
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private JGKSingleton()
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{
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super();
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}
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public static JGKSingleton getInstance()
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{
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/* in a non-thread-safe version of a Singleton the following line could be executed, and the */
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/* thread could be immediately swapped out */
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if (instance_ == null)
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{
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synchronized(syncObject_)
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{
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if (instance_ == null)
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{
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instance_ = new JGKSingleton();
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}
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}
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}
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return instance_;
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}
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}
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