使用UrlConnection实现后台模拟http请求的简单实例
使用UrlConnection实现后台模拟http请求的简单实例
这两天在整理看httpclient，然后想自己用UrlConnection后台模拟实现Http请求，于是一个简单的小例子就新鲜出炉了（支持代理哦）：
publicclassSimpleHttpTest{
publicstaticStringsend(StringurlStr,Map<String,String>map,Stringencoding){
Stringbody="";
StringBuffersbuf=newStringBuffer();
if(map!=null){
for(Entry<String,String>entry:map.entrySet()){
sbuf.append(entry.getKey()).append("=").append(entry.getValue()).append("&");
}
if(sbuf.length()>0){
sbuf.deleteCharAt(sbuf.length()-1);
}
}
//1、重新对请求报文进行GBK编码
byte[]postData=null;
try{
postData=sbuf.toString().getBytes(encoding);
}catch(UnsupportedEncodingExceptione){
e.printStackTrace();
}
//2、发送HTTP(S)请求
OutputStreamreqStream=null;
InputStreamresStream=null;
URLConnectionrequest=null;
try{
System.out.println("交易请求地址："+urlStr);
System.out.println("参数："+sbuf.toString());
//A、与服务器建立HTTP(S)连接
URLurl=null;
try{
Proxyproxy=newProxy(java.net.Proxy.Type.HTTP,newInetSocketAddress("127.0.0.1",8087));
url=newURL(urlStr);
request=url.openConnection(proxy);
request.setDoInput(true);
request.setDoOutput(true);
}catch(MalformedURLExceptione){
e.printStackTrace();
}catch(IOExceptione){
e.printStackTrace();
}
//B、指定报文头【Content-type】、【Content-length】与【Keep-alive】
request.setRequestProperty("Content-type","application/x-www-form-urlencoded");
request.setRequestProperty("Content-length",String.valueOf(postData.length));
request.setRequestProperty("Keep-alive","false");
request.setRequestProperty("User-Agent","Mozilla/4.0(compatible;MSIE5.0;WindowsNT;DigExt)");
//C、发送报文至服务器
reqStream=request.getOutputStream();
reqStream.write(postData);
reqStream.close();
//D、接收服务器返回结果
ByteArrayOutputStreamms=null;
resStream=request.getInputStream();
ms=newByteArrayOutputStream();
byte[]buf=newbyte[4096];
intcount;
while((count=resStream.read(buf,0,buf.length))>0){
ms.write(buf,0,count);
}
resStream.close();
body=newString(ms.toByteArray(),encoding);
}catch(UnknownHostExceptione){
System.err.println("服务器不可达【"+e.getMessage()+"】");
}catch(IOExceptione){
e.printStackTrace();
}finally{
try{
if(reqStream!=null)
reqStream.close();
if(resStream!=null)
resStream.close();
}catch(Exceptionex){
}
}
System.out.println("交易响应结果：");
System.out.println(body);
returnbody;
}
publicstaticvoidmain(String[]args){
Stringurl="http://php.weather.sina.com.cn/iframe/index/w_cl.php";
Map<String,String>map=newHashMap<String,String>();
map.put("code","js");
map.put("day","0");
map.put("city","上海");
map.put("dfc","1");
map.put("charset","utf-8");
send(url,map,"utf-8");
}
}
结果如下：
交易请求地址：http://php.weather.sina.com.cn/iframe/index/w_cl.php
参数：dfc=1&charset=utf-8&day=0&code=js&city=上海
交易响应结果：
(function(){varw=[];w['上海']=[{s1:'阴',s2:'阴',f1:'yin',f2:'yin',t1:'17',t2:'14',p1:'≤3',p2:'≤3',
d1:'东北风',d2:'东北风'}];varadd={now:'2015-11-1119:04:33',time:'1447239873',update:'
北京时间11月11日17:10更新',error:'0',total:'1'};window.SWther={w:w,add:add};})();//0
代码中的步骤写的很明白了，如果你有心，还可以对该方法进行各种封装，方便使用。下篇我会分享一下httpclient是如何模拟后台来发送http请求的，还有配置ssl、代理、自定义header等等，敬请期待吧。
感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！