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| Code Block | ||
|---|---|---|
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public class MySingleton {
private static MySingleton _instance;
private MySingleton() {
// construct object . .
// private constructor prevents instantiation by outside callers
}
// lazy initialization
public static synchronized MySingleton getInstance() {
if (_instance==null) {
_instance = new MySingleton();
}
return _instance;
}
public Object clone() throws CloneNotSupportedException {
throw new CloneNotSupportedException();
}
// Remainder of class definition . . .
}
|
See MSC05- J Make your classes non Cloneable unless required for more details about restricting the clone() method.
Risk Assessment
Using lazy initialization of a Singleton without synchronizing the getInstance()method may lead in multiple instances.
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