Java中更换Map中的主键key的名称
package action;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class TestMap {
public static void main(String[] args) {
List<HashMap<String, String>> mapList = new ArrayList<HashMap<String, String>>();
HashMap<String, String> map = new HashMap<String, String>();
map.put("extdate", "6");
map.put("extdate1", "2");
map.put("extdate2", "3");
for(Object obj : map.keySet()){
Object value = map.get(obj);
System.out.println(obj+":"+value);
}
mapList.add(map);
for(HashMap<String, String> maps:mapList) {
maps.put("B", maps.remove("extdate"));
}
System.out.println("=======================");
for(HashMap<String, String> mapa:mapList) {
for(Object obj : mapa.keySet()){
Object value = mapa.get(obj);
System.out.println(obj+":"+value);
}
}
}
}