1.懶漢式
public class singleinstance1
private static singleinstance1 instance;
public static singleinstance1 getinstance()
return instance;
}}
public class singleinstance1
private static singleinstance1 instance;
public synchronized static singleinstance1 getinstance()
return instance;
}}
2.餓漢式
public class singleinstance2
private static singleinstance2 instance = new singleinstance2();
public static singleinstance2 getinstance()
}
3.延長初始化佔位類模式
public class singleinstance3
private static class singleinstance3holder
public static singleinstance3 getinstance()
}
4.dcl
public class singleinstance4
private static singleinstance4 instance;
public static singleinstance4 getinstance()
}} return instance;
}}
5.dcl改進
public class singleinstance5
private static volatile singleinstance5 instance;
public static singleinstance5 getinstance()
}} return instance;
}}
綜上,建議使用延遲初始化佔位類模式的單利模式
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