Question

List<实体> list = new List<实体>(); 如何去掉里面重复的数据

Answer 1

新建一个set，然后将list中的数据add进去

Answer 2

public static ArrayList<String> getSame(String[] str){
ArrayList<String> list=new ArrayList<String>();
String[] newStr=new String[str.length];
int index=0;
for (int i = 0; i < str.length; i++) {
boolean contained =false;
for (int j = 0; j < index; j++){
if (str[i].equals(newStr[j])) {
contained = true;
break;
}
}
if(!contained) newStr[index++]=str[i];
}
String[] resultStr=new String[index];
System.arraycopy(newStr, 0, resultStr, 0, index);
for (int i = 0; i < resultStr.length; i++) {
list.add(resultStr[i]);
}
return list;
}

Answer 3

去重复的话别用list，用hashset