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Class Model<T>{

   private T t;

   .....


   private void someMethod(){
       //now t is null
       Class c = t.getClass();
   } 

   .....

}

Of course it throws NPE.

Class c = t.getClass();

What syntax should i use to get class of T if my instance is null? Is it possible?

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1 Answer

It's not possible due to type erasure.

There is the following workaround:

class Model<T> { 

    private T t; 
    private Class<T> tag;

    public Model(Class<T> tag) {
       this.tag = tag;
    }

    private void someMethod(){ 
       // use tag
    }  
} 

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
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