代码如下：
package com.yanek.util;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
public class HttpUtil {
/**
* @param args
*/
public static void main(String[] args) {
Map<String, String> paramValues = new HashMap<String, String>();
paramValues.put("b", "2");
paramValues.put("a", "1");
paramValues.put("c","3");
paramValues.put("d","4");
paramValues.put("e","5");
System.out.println("post params：：：："+getParams("post",paramValues));
System.out.println("get params：：：："+getParams("get",paramValues));
System.out.println("post params：：：："+getParamsOrderByKey("post",paramValues));
System.out.println("get params：：：："+getParamsOrderByKey("get",paramValues));
}
/**
* 得到参数列表字符串
* @param method 请求类型 get or post
* @param paramValues 参数map对象
* @return 参数列表字符串
*/
public static String getParams(String method,Map<String, String> paramValues)
{
String params="";
Set<String> key = paramValues.keySet();
String beginLetter="";
if (method.equalsIgnoreCase("get"))
{
beginLetter="?";
}
for (Iterator<String> it = key.iterator(); it.hasNext();) {
String s = (String) it.next();
if (params.equals(""))
{
params += beginLetter + s + "=" + paramValues.get(s);
}
else
{
params += "&" + s + "=" + paramValues.get(s);
}
}
return params;
}
/**
* 按照key排序得到参数列表字符串
* @param method 请求类型 get or post
* @param paramValues 参数map对象
* @return 参数列表字符串
*/
public static String getParamsOrderByKey(String method,Map<String, String> paramValues)
{
String params="";
Set<String> key = paramValues.keySet();
String beginLetter="";
if (method.equalsIgnoreCase("get"))
{
beginLetter="?";
}
List<String> paramNames = new ArrayList<String>(paramValues.size());
paramNames.addAll(paramValues.keySet());
Collections.sort(paramNames);
for (String paramName : paramNames) {
if (params.equals(""))
{
params += beginLetter + paramName + "=" + paramValues.get(paramName);
}
else
{
params += "&" + paramName + "=" + paramValues.get(paramName);
}
}
return params;
}
}
输出如下：
post params：：：：d=4&e=5&b=2&c=3&a=1 get params：：：：?d=4&e=5&b=2&c=3&a=1 post params：：：：a=1&b=2&c=3&d=4&e=5 get params：：：：?a=1&b=2&c=3&d=4&e=5
