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java 利用范型返回动态类型

2010-07-01 11:16:30| 分类： java | 标签： |举报 |字号大中小订阅

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public class Test{
        public <T> T toDo(Class<T> clazz){
                    //do something...
         }
         public static void main(String[] args){
                      Test t=new Test();
                      User u=t.toDo(User.class);
                      Student s=t.toDo(Student.class);
         }
}
我们可以利用这个特性建立一个基础的DAO类，让这个类可以操作和返回任意的 POJO。而且主要是返回类型不再需要强制转换为指定的POJO。

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