List元素去重复方法集

1. 循环list中的所有元素然后删除重复
   
   
   

1. public   static   List  removeDuplicate(List list)  {       
2. for  ( int  i  =   0 ; i  <  list.size()  -   1 ; i ++ )  {       
3. for  ( int  j  =  list.size()  -   1 ; j  >  i; j -- )  {       
4. if  (list.get(j).equals(list.get(i)))  {       
5.               list.remove(j);       
6.             }        
7.         }        
8.       }        
9. return list;       
10. }

2. 通过HashSet踢除重复元素

1. public static List removeDuplicate(List list) {   
2. HashSet h = new HashSet(list);   
3. list.clear();   
4. list.addAll(h);   
5. return list;   
6. }

3. 删除ArrayList中重复元素，保持顺序

1. // 删除ArrayList中重复元素，保持顺序     
2. public static void removeDuplicateWithOrder(List list) {    
3. new HashSet();    
4. new ArrayList();    
5. for (Iterator iter = list.iterator(); iter.hasNext();) {    
6.          Object element = iter.next();    
7. if (set.add(element))    
8.             newList.add(element);    
9.       }     
10.      list.clear();    
11.      list.addAll(newList);    
12. " remove duplicate " + list);    
13.  }

4.把list里的对象遍历一遍，用list.contain()，如果不存在就放入到另外一个list集合中

1. public static List removeDuplicate(List list){  
2. new ArrayList();  
3. for(int i=0;i<list.size();i++){  
4. if(!listTemp.contains(list.get(i))){  
5.                 listTemp.add(list.get(i));  
6.             }  
7.         }  
8. return listTemp;  
9.     }