如何通过Java发送HTTP请求,通俗点讲,如何通过Java(模拟浏览器)发送HTTP请求。下面是由本站小编为大家整理的java如何利用onnection发送HTTP请求,喜欢的可以收藏一下!了解更多详情资讯,请关注应届毕业生考试网!
运用原生Java Api发送简单的Get请求、Post请求步骤
1.通过统一资源定位器()获取连接器(onnection)
2.设置请求的参数
3.发送请求
4.以输入流的.形式获取返回内容
5.关闭输入流
发送请求与接收响应流类 HttpRequestor
package ;
import eredReader;
import ception;
import tStream;
import tStreamReader;
import utStream;
import utStreamWriter;
import URLConnection;
import SocketAddress;
import y;
import ;
import onnection;
import ator;
import ;
public class HttpRequestor {
private String charset = "utf-8";
private Integer connectTimeout = null;
private Integer socketTimeout = null;
private String proxyHost = null;
private Integer proxyPort = null;
/**
* Do GET request
* @param url
* @return
* @throws Exception
* @throws IOException
*/
public String doGet(String url) throws Exception {URL localURL = new URL(url);
URLConnection connection = Connection(localURL);HttpURLConnection httpURLConnection = (HttpURLConnection)connection;equestProperty("Accept-Charset", charset);equestProperty("Content-Type", "application/x-www-form-urlencoded");InputStream inputStream = null;
InputStreamReader inputStreamReader = null;BufferedReader reader = null;
StringBuffer resultBuffer = new StringBuffer();String tempLine = null;
//响应失败
if (esponseCode() >= 300) {throw new Exception("HTTP Request is not success, Response code is " + esponseCode());}
try {
inputStream = nputStream();inputStreamReader = new InputStreamReader(inputStream);reader = new BufferedReader(inputStreamReader);while ((tempLine = Line()) != null) {nd(tempLine);
}
} finally {
if (reader != null) {
e();
}
if (inputStreamReader != null) {
e();
}
if (inputStream != null) {
e();
}
}
return ring();
}
/**
* Do POST request
* @param url
* @param parameterMap
* @return
* @throws Exception
*/
public String doPost(String url, Map parameterMap) throws Exception {/* Translate parameter map to parameter date string */StringBuffer parameterBuffer = new StringBuffer();if (parameterMap != null) {
Iterator iterator = et()ator();String key = null;
String value = null;
while (ext()) {
key = (String)();
if ((key) != null) {
value = (String)(key);
} else {
value = "";
}
nd(key)nd("=")nd(value);if (ext()) {
nd("&");
}
}
}
tln("POST parameter : " + ring());URL localURL = new URL(url);
URLConnection connection = Connection(localURL);HttpURLConnection httpURLConnection = (HttpURLConnection)connection;oOutput(true);
equestMethod("POST");equestProperty("Accept-Charset", charset);equestProperty("Content-Type", "application/x-www-form-urlencoded");equestProperty("Content-Length", eOf(th()));OutputStream outputStream = null;
OutputStreamWriter outputStreamWriter = null;InputStream inputStream = null;
InputStreamReader inputStreamReader = null;BufferedReader reader = null;
StringBuffer resultBuffer = new StringBuffer();String tempLine = null;
try {
outputStream = utputStream();outputStreamWriter = new OutputStreamWriter(outputStream);e(ring());h();
//响应失败
if (esponseCode() >= 300) {throw new Exception("HTTP Request is not success, Response code is " + esponseCode());}
//接收响应流
inputStream = nputStream();inputStreamReader = new InputStreamReader(inputStream);reader = new BufferedReader(inputStreamReader);while ((tempLine = Line()) != null) {nd(tempLine);
}
} finally {
if (outputStreamWriter != null) {
e();
}
if (outputStream != null) {
e();
}
if (reader != null) {
e();
}
if (inputStreamReader != null) {
e();
}
if (inputStream != null) {
e();
}
}
return ring();
}
private URLConnection openConnection(URL localURL) throws IOException {URLConnection connection;
if (proxyHost != null && proxyPort != null) {Proxy proxy = new Proxy(, new InetSocketAddress(proxyHost, proxyPort));connection = Connection(proxy);} else {
connection = Connection();
}
return connection;
}
/**
* Render request according setting
* @param request
*/
private void renderRequest(URLConnection connection) {if (connectTimeout != null) {
onnectTimeout(connectTimeout);}
if (socketTimeout != null) {
eadTimeout(socketTimeout);}
}
/*
* Getter & Setter
*/
public Integer getConnectTimeout() {
return connectTimeout;
}
public void setConnectTimeout(Integer connectTimeout) {ectTimeout = connectTimeout;
}
public Integer getSocketTimeout() {
return socketTimeout;
}
public void setSocketTimeout(Integer socketTimeout) {etTimeout = socketTimeout;
}
public String getProxyHost() {
return proxyHost;
}
public void setProxyHost(String proxyHost) {yHost = proxyHost;
}
public Integer getProxyPort() {
return proxyPort;
}
public void setProxyPort(Integer proxyPort) {yPort = proxyPort;
}
public String getCharset() {
return charset;
}
public void setCharset(String charset) {
set = charset;
}
}
为测试方便,新建一个项目,并新建一个Servlet,接收post请求并对HttpRequestor请求响应,发出响应流:此处使用了
注解: @WebServlet("/LoginServlet") ,也可以在配置Servletpackage nServlet;
import ception;
import letException;
import ervlet;import Servlet;
import ServletRequest;import ServletResponse;/**
* Servlet implementation class LoginServlet*/
@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {private static final long serialVersionUID = 1L;/**
* @see HttpServlet#HttpServlet()
*/
public LoginServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stub
tln("111");
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stub
String username = arameter("username");String blog = arameter("blog");tln(username);
tln(blog);
ontentType("text/plain; charset=UTF-8");haracterEncoding("UTF-8");
//响应流
riter()e("It is ok!");
}
}
测试类
package ;
import Map;
import ;
public class Test {
public static void main(String[] args) {
/* Post Request */
Map dataMap = new HashMap();
("username", "Nick Huang");
("blog", "IT");
try {
tln(new HttpRequestor()st("http://localhost:8081/TestProgect2/LoginServlet", dataMap));//tln(new HttpRequestor()t("http://localhost:8081/TestProgect2/LoginServlet"));} catch (Exception e) {
// TODO Auto-generated catch block
tStackTrace();
}
/* Get Request */
}
}
1.接收post请求类LoginServlet,控制台测试结果Requestor接收LoginServlet返回的流
OK,完成
对于接收TestProgect2项目中类返回的流,在真实环境中可能是异步接收返回的流的,当一台机器A向另外一台机器B发送请求,B接收到A的信息,将信息处理后,需要将处理结果返回即响应返回给A,A会接收到B返回的信息可以另外建一个Servlet类来专门异步接收返回的信息package ;
import eredReader;
import ception;
import tStream;
import tStreamReader;
import letException;
import ervlet;import Servlet;
import ServletRequest;import ServletResponse;/**
* Servlet implementation class HttpListenerServlet*/
@WebServlet("/HttpListenerServlet")
public class HttpListenerServlet extends HttpServlet {private static final long serialVersionUID = 1L;/**
* @see HttpServlet#HttpServlet()
*/
public HttpListenerServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stub
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stub
InputStream inputStream = null;
inputStream = nputStream();
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);BufferedReader reader = new BufferedReader(inputStreamReader);String tempLine = null;
StringBuffer resultBuffer=new StringBuffer();while ((tempLine = Line()) != null) {nd(tempLine);
}
tln(ring());}
}