JavaʵÏÖ½«Mapת»»ÎªListµÄС´úÂë
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
public class ConvertMapToList {
/**
* ʵÏÖ½«HashMapת»»³ÉΪArrayList£¬²¢½«mapµÄKey ¡¢Value·Ö±ð´æ·Åµ½Á½¸öArrayListµ±ÖÐ
* @param args
*/
public static void main(String[] args) {
Map map = new HashMap();
map.put("a", "a1");
map.put("b", "b1");
map.put("c", "c1");
List listKey = new ArrayList();
List listValue = new ArrayList();
Iterator it = map.keySet().iterator();
while (it.hasNext()) {
String key = it.next().toString();
listKey.add(key);
listValue.add(map.get(key));
}
System.out.println("Convert Finished !");
//output the context of the ArrayList
for(int i =0 ;i<listKey.size();i++){
System.out.print("Key :"+listKey.get(i));
System.out.println(" Value :"+listValue.get(i));
}
}
}
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2.ÏòmapÖзÅÖµ,×¢Ò⣺mapÊÇkey-valueµÄÐÎʽ´æ·ÅµÄ.Èç:
map.put("sa","dd");
3.´ÓmapÖÐȡֵ:String str = map.get("sa").toString();½á¹ûÊÇ:str = "dd";
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JDK1.5
Map m = new HashMap();
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Map map = new HashMap();
Iterator it = map.entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry) it.next();
Object key = e ......