发表新帖
发表新帖

What are the risks of explicitly casting from a list of type List<? extends MyObject> to a list of type List in Java?

后端 未结
关注
5 1162
说谎
说谎 2021-01-12 16:26

I think the title should explain it all but just in case...

I want to know what risks and potential issues relating to casting can arise from the following snippet o

5条回答
  • 迷失自我
    迷失自我 (楼主)
    2021-01-12 16:27

    This is similar to 

    List obj = (List) new ArrayList();



    I hope the problem is evident. List of subtypes can't be cast to Lists of supertypes. 
    
    
    
             
    
                                                        
    
            
            
    
              
                
                0
              
                   
                
               讨论(0)
              
                                                  
              
              
    
                          
             
       
          
              
    
                                       
    

    

                
    
                         
          
                              			
        
        
        
    
          
    
            
            
    
              
              
    
            
    


                                 
              
    
            
    
                          
    

        
         
    
                
                
    
                  
                
    
                
    
                   看不清?
                
    
              
    
                                  
    
                    
   
                 
             
              
    提交回复
    
            
    
          
    
        
    
      
       
      
    
    
    
          
 
     
 
    
        
    热议问题