java Map几种循环遍历方法小结

标注：由于平时写代码用到循环方法比较多，总结几种比较实用的循环

一、循环遍历JSONObject

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import net.sf.json.JSONObject;

@SuppressWarnings({ "rawtypes" })
public class JsonToMap {
public static void main(String[] args) {
System.out.println(getMapFromJsonObjStr("{\"operator\":\"yes\",\"name\":\"fangyukang\"}").toString());
}

public static Map getMapFromJsonObjStr(String jsonObjStr) {
JSONObject jsonObject = JSONObject.fromObject(jsonObjStr);
Map<String, Object> map = new HashMap<String, Object>();
for (Iterator iter = jsonObject.keys(); iter.hasNext();) {
String key = (String) iter.next();
map.put(key, jsonObject.get(key));
}
return map;
}
}

二、for循环（写的比较多的 for(int i=0;i<temp.size();i++){} 这种写法真心没有for循环好用）

List<Map<String, Object>> itemList = null;
for(Map<String, Object> map : itemList){
map.get(key);
map.put(key,value);
map.remove(key);
}

三、用for循环遍历Entry 得到Map ----------->key,value

public static String Post(String url, Map<String, Object> params){
try {
List<NameValuePair> param = new ArrayList<NameValuePair>();
NameValuePair nvp;
if (params != null) {
for (Entry<String, Object> entry : params.entrySet()) {
Object key = entry.getKey();
Object value = entry.getValue();
nvp = new BasicNameValuePair(
key.toString(), value.toString());
param.add(nvp);
}
}
return Request.Post(url)
.bodyForm(param, Charset.forName("utf-8")).execute()
.returnContent().asString();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}