
让我们看看将执行什么:
main()创建一个新的实例
ObjectTest
ObjectTest类有一个字段
instanceObj,其将包含一个
ObjectTest
instanceObj用新的in初始化
ObjectTest
我认为您想要更多类似这样的东西:
public class ObjectTest { private static ObjectTest instanceObj; private ObjectTest() { } public static ObjectTest getInstance() { if (instanceObj != null) { instanceObj = new ObjectTest(); } return instanceObj; } public static void main(String[] args) { ObjectTest localObj = ObjectTest.getInstance(); }}或这个 :
public class ObjectTest { private static final ObjectTest instanceObj = new ObjectTest(); private ObjectTest() { } public static ObjectTest getInstance() { return instanceObj; } public static void main(String[] args) { ObjectTest localObj = ObjectTest.getInstance(); }}这是单例模式。