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Java Generics: List, List<Object>, List<?>

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你的背包 2020-11-22 17:08

Can someone explained, as detailed as possible, the differences between the following types?

List
List
List



Let me m         


        
      
      
      

        

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                 一生所求 
              
              
    
                
                   一生所求
                                             
                
                
                (楼主)
            
              
                  
    
                2020-11-22 17:54
              
    

            
    
            
    
              
              

    Simplest explanation which is not "RTFM":
    


    List

    


    Will generate lots of compiler warnings, but is mostly equivalent to:
    


    List



    While:
    


    List

    


    basically means its something generic, but you don't know what the generic type is.  Its great for getting rid of compiler warnings when you cant modify the return types of other things that just returned List.  Its much more useful in the form:
    


    List

    
    
    
             
    
                                                        
    
            
            
    
              
                
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