黑马程序员————单例设计模式

<pre name="code" class="java"><pre name="code" class="java">public class Ehan {
private static Ehan ehan = new ehan;
private ehan(){}
public static ehan getInstance(){
return ehan;
}
}

<pre name="code" class="java">public class Ehan {
private static Ehan ehan =null;
private ehan(){}
public static ehan getInstance(){
if(ehan==null<span style="font-family: Arial, Helvetica, sans-serif;">) </span><span style="font-family: Arial, Helvetica, sans-serif;"> </span>

<span style="white-space:pre"></span><pre name="code" class="java">                synchronized(Object o){
if(ehan==null)
ehan=new Ehan();
}
return ehan;
}

}