发表新帖
发表新帖

Get generic type of java.util.List

后端 未结
关注
14 2666
广开言路
广开言路 2020-11-22 02:06

I have;

List stringList = new ArrayList();
List integerList = new ArrayList();

Is

14条回答
  • 面向向阳花
    面向向阳花 (楼主)
    2020-11-22 02:43

    Had the same problem, but I used instanceof instead. Did it this way:

    List listCheck = (List)(Object) stringList;
    if (!listCheck.isEmpty()) {
       if (listCheck.get(0) instanceof String) {
           System.out.println("List type is String");
       }
       if (listCheck.get(0) instanceof Integer) {
           System.out.println("List type is Integer");
       }
    }
}



    This involves using unchecked casts so only do this when you know it is a list, and what type it can be. 
    
    
    
             
    
                                                        
    
            
            
    
              
                
                0
              
                   
                
               讨论(0)
              
                                                  
              
              
    
                          
             
       
          
              
    
                                       
    

    

                
    
                         
          
                              			
        
        
        
    
          
    
            
            
    
              
              
    
            
    


                                 
              
    
            
    
                          
    

        
         
    
                
                
    
                  
                
    
                
    
                   看不清?
                
    
              
    
                                  
    
                    
   
                 
             
              
    提交回复
    
            
    
          
    
        
    
      
       
      
    
    
    
          
 
     
 
    
        
    热议问题