前面的文章中，我们曾经实现了一个HTTP的GET 和 POST 请求；
此处我封装了一个HTTP的get和post的辅助类，能够更好的使用；
类名：HttpRequestUtil
提供了如下功能：
(1)模拟GET请求；
(2)模拟POST请求；
(3)模拟文件上传请求；
(4)发送XML数据；
发送GET请求
参数：
(1)url：单纯的URL，不带任何参数；
(2)params：参数；
(3)headers：需要设置的HTTP请求头；
返回：
HttpURLConnection
发送POST请求
(2)public static URLConnection sendPostRequest(String url, Map<String, String> params, Map<String, String> headers)
参数：
(1)url：单纯的URL，不带任何参数；
(2)params：参数；
(3)headers：需要设置的HTTP请求头；
返回：
HttpURLConnection
文件上传
(3)public static boolean uploadFiles(String url, Map<String, String> params, FormFile[] files)
参数：
(1)url：单纯URL
(2)params：参数；
(3)files：多个文件
返回：是否上传成功
(4)public static boolean uploadFile(String path, Map<String, String> params, FormFile file)
参数：
(1)url：单纯URL
(2)params：参数；
(3)file：一个文件
返回：是否上传成功
发送XML数据
(5)public static byte[] postXml(String url, String xml, String encoding)
参数：
(1)url：单纯URL
(2)xml：XML数据
(3)XML数据编码
对于上传文件，FormFile的构造函数声明如下：
(1)public FormFile(String filname, byte[] data, String parameterName, String contentType)
参数：
(1)filname：文件的名称
(2)data：文件的数据
(3)parameterName：HTML的文件上传控件的参数的名字
(4)contentType：文件类型，比如text/plain为txt
(2)public FormFile(String filname, File file, String parameterName, String contentType)
参数：
(1)filname：文件的名称
(2)file：文件名
(3)parameterName：HTML的文件上传控件的参数的名字
(4)contentType：文件类型，比如text/plain为txt
FormFile.java
package com.xiazdong.netword.http.util;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.InputStream;/** * 上传文件 */public class FormFile { /* 上传文件的数据 */ private byte[] data; private InputStream inStream; private File file; /* 文件名称 */ private String filname; /* 请求参数名称*/ private String parameterName; /* 内容类型 */ private String contentType = "application/octet-stream"; /** * 此函数用来传输小文件 * @param filname * @param data * @param parameterName * @param contentType */ public FormFile(String filname, byte[] data, String parameterName, String contentType) { this.data = data; this.filname = filname; this.parameterName = parameterName; if(contentType!=null) this.contentType = contentType; } /** * 此函数用来传输大文件 * @param filname * @param file * @param parameterName * @param contentType */ public FormFile(String filname, File file, String parameterName, String contentType) { this.filname = filname; this.parameterName = parameterName; this.file = file; try { this.inStream = new FileInputStream(file); } catch (FileNotFoundException e) { e.printStackTrace(); } if(contentType!=null) this.contentType = contentType; } public File getFile() { return file; } public InputStream getInStream() { return inStream; } public byte[] getData() { return data; } public String getFilname() { return filname; } public void setFilname(String filname) { this.filname = filname; } public String getParameterName() { return parameterName; } public void setParameterName(String parameterName) { this.parameterName = parameterName; } public String getContentType() { return contentType; } public void setContentType(String contentType) { this.contentType = contentType; } }HttpRequestUtil.java
package com.xiazdong.netword.http.util;import java.io.BufferedReader;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.InputStream;import java.io.InputStreamReader;import java.io.OutputStream;import java.net.HttpURLConnection;import java.net.InetAddress;import java.net.Socket;import java.net.URL;import java.net.URLConnection;import java.net.URLEncoder;import java.util.HashMap;import java.util.Map;import java.util.Map.Entry;import java.util.Set;/* * 此类用来发送HTTP请求 * */public class HttpRequestUtil { /** * 发送GET请求 * @param url * @param params * @param headers * @return * @throws Exception */ public static URLConnection sendGetRequest(String url, Map<String, String> params, Map<String, String> headers) throws Exception { StringBuilder buf = new StringBuilder(url); Set<Entry<String, String>> entrys = null; // 如果是GET请求，则请求参数在URL中 if (params != null && !params.isEmpty()) { buf.append("?"); entrys = params.entrySet(); for (Map.Entry<String, String> entry : entrys) { buf.append(entry.getKey()).append("=") .append(URLEncoder.encode(entry.getValue(), "UTF-8")) .append("&"); } buf.deleteCharAt(buf.length() - 1); } URL url1 = new URL(buf.toString()); HttpURLConnection conn = (HttpURLConnection) url1.openConnection(); conn.setRequestMethod("GET"); // 设置请求头 if (headers != null && !headers.isEmpty()) { entrys = headers.entrySet(); for (Map.Entry<String, String> entry : entrys) { conn.setRequestProperty(entry.getKey(), entry.getValue()); } } conn.getResponseCode(); return conn; } /** * 发送POST请求 * @param url * @param params * @param headers * @return * @throws Exception */ public static URLConnection sendPostRequest(String url, Map<String, String> params, Map<String, String> headers) throws Exception { StringBuilder buf = new StringBuilder(); Set<Entry<String, String>> entrys = null; // 如果存在参数，则放在HTTP请求体，形如name=aaa&age=10 if (params != null && !params.isEmpty()) { entrys = params.entrySet(); for (Map.Entry<String, String> entry : entrys) { buf.append(entry.getKey()).append("=") .append(URLEncoder.encode(entry.getValue(), "UTF-8")) .append("&"); } buf.deleteCharAt(buf.length() - 1); } URL url1 = new URL(url); HttpURLConnection conn = (HttpURLConnection) url1.openConnection(); conn.setRequestMethod("POST"); conn.setDoOutput(true); OutputStream out = conn.getOutputStream(); out.write(buf.toString().getBytes("UTF-8")); if (headers != null && !headers.isEmpty()) { entrys = headers.entrySet(); for (Map.Entry<String, String> entry : entrys) { conn.setRequestProperty(entry.getKey(), entry.getValue()); } } conn.getResponseCode(); // 为了发送成功 return conn; } /** * 直接通过HTTP协议提交数据到服务器,实现如下面表单提交功能: * <FORM METHOD=POST ACTION="http://192.168.0.200:8080/ssi/fileload/test.do" enctype="multipart/form-data"> <INPUT TYPE="text" NAME="name"> <INPUT TYPE="text" NAME="id"> <input type="file" name="imagefile"/> <input type="file" name="zip"/> </FORM> * @param path 上传路径(注：避免使用localhost或127.0.0.1这样的路径测试，因为它会指向手机模拟器，你可以使用http://www.itcast.cn或http://192.168.1.10:8080这样的路径测试) * @param params 请求参数 key为参数名,value为参数值 * @param file 上传文件 */ public static boolean uploadFiles(String path, Map<String, String> params, FormFile[] files) throws Exception{ final String BOUNDARY = "---------------------------7da2137580612"; //数据分隔线 final String endline = "--" + BOUNDARY + "--\r\n";//数据结束标志 int fileDataLength = 0; if(files!=null&&files.length!=0){ for(FormFile uploadFile : files){//得到文件类型数据的总长度 StringBuilder fileExplain = new StringBuilder(); fileExplain.append("--"); fileExplain.append(BOUNDARY); fileExplain.append("\r\n"); fileExplain.append("Content-Disposition: form-data;name=\""+ uploadFile.getParameterName()+"\";filename=\""+ uploadFile.getFilname() + "\"\r\n"); fileExplain.append("Content-Type: "+ uploadFile.getContentType()+"\r\n\r\n"); fileExplain.append("\r\n"); fileDataLength += fileExplain.length(); if(uploadFile.getInStream()!=null){ fileDataLength += uploadFile.getFile().length(); }else{ fileDataLength += uploadFile.getData().length; } } } StringBuilder textEntity = new StringBuilder(); if(params!=null&&!params.isEmpty()){ for (Map.Entry<String, String> entry : params.entrySet()) {//构造文本类型参数的实体数据 textEntity.append("--"); textEntity.append(BOUNDARY); textEntity.append("\r\n"); textEntity.append("Content-Disposition: form-data; name=\""+ entry.getKey() + "\"\r\n\r\n"); textEntity.append(entry.getValue()); textEntity.append("\r\n"); } } //计算传输给服务器的实体数据总长度 int dataLength = textEntity.toString().getBytes().length + fileDataLength + endline.getBytes().length; URL url = new URL(path); int port = url.getPort()==-1 ? 80 : url.getPort(); Socket socket = new Socket(InetAddress.getByName(url.getHost()), port); OutputStream outStream = socket.getOutputStream(); //下面完成HTTP请求头的发送 String requestmethod = "POST "+ url.getPath()+" HTTP/1.1\r\n"; outStream.write(requestmethod.getBytes()); String accept = "Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*\r\n"; outStream.write(accept.getBytes()); String language = "Accept-Language: zh-CN\r\n"; outStream.write(language.getBytes()); String contenttype = "Content-Type: multipart/form-data; boundary="+ BOUNDARY+ "\r\n"; outStream.write(contenttype.getBytes()); String contentlength = "Content-Length: "+ dataLength + "\r\n"; outStream.write(contentlength.getBytes()); String alive = "Connection: Keep-Alive\r\n"; outStream.write(alive.getBytes()); String host = "Host: "+ url.getHost() +":"+ port +"\r\n"; outStream.write(host.getBytes()); //写完HTTP请求头后根据HTTP协议再写一个回车换行 outStream.write("\r\n".getBytes()); //把所有文本类型的实体数据发送出来 outStream.write(textEntity.toString().getBytes()); //把所有文件类型的实体数据发送出来 if(files!=null&&files.length!=0){ for(FormFile uploadFile : files){ StringBuilder fileEntity = new StringBuilder(); fileEntity.append("--"); fileEntity.append(BOUNDARY); fileEntity.append("\r\n"); fileEntity.append("Content-Disposition: form-data;name=\""+ uploadFile.getParameterName()+"\";filename=\""+ uploadFile.getFilname() + "\"\r\n"); fileEntity.append("Content-Type: "+ uploadFile.getContentType()+"\r\n\r\n"); outStream.write(fileEntity.toString().getBytes()); if(uploadFile.getInStream()!=null){ byte[] buffer = new byte[1024]; int len = 0; while((len = uploadFile.getInStream().read(buffer, 0, 1024))!=-1){ outStream.write(buffer, 0, len); } uploadFile.getInStream().close(); }else{ outStream.write(uploadFile.getData(), 0, uploadFile.getData().length); } outStream.write("\r\n".getBytes()); } } //下面发送数据结束标志，表示数据已经结束 outStream.write(endline.getBytes()); BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream())); if(reader.readLine().indexOf("200")==-1){//读取web服务器返回的数据，判断请求码是否为200，如果不是200，代表请求失败 return false; } outStream.flush(); outStream.close(); reader.close(); socket.close(); return true; } /** * 提交数据到服务器 * @param path 上传路径(注：避免使用localhost或127.0.0.1这样的路径测试，因为它会指向手机模拟器，你可以使用http://www.itcast.cn或http://192.168.1.10:8080这样的路径测试) * @param params 请求参数 key为参数名,value为参数值 * @param file 上传文件 */ public static boolean uploadFile(String path, Map<String, String> params, FormFile file) throws Exception{ return uploadFiles(path, params, new FormFile[]{file}); } /** * 将输入流转为字节数组 * @param inStream * @return * @throws Exception */ public static byte[] read2Byte(InputStream inStream)throws Exception{ ByteArrayOutputStream outSteam = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = 0; while( (len = inStream.read(buffer)) !=-1 ){ outSteam.write(buffer, 0, len); } outSteam.close(); inStream.close(); return outSteam.toByteArray(); } /** * 将输入流转为字符串 * @param inStream * @return * @throws Exception */ public static String read2String(InputStream inStream)throws Exception{ ByteArrayOutputStream outSteam = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = 0; while( (len = inStream.read(buffer)) !=-1 ){ outSteam.write(buffer, 0, len); } outSteam.close(); inStream.close(); return new String(outSteam.toByteArray(),"UTF-8"); } /** * 发送xml数据 * @param path 请求地址 * @param xml xml数据 * @param encoding 编码 * @return * @throws Exception */ public static byte[] postXml(String path, String xml, String encoding) throws Exception{ byte[] data = xml.getBytes(encoding); URL url = new URL(path); HttpURLConnection conn = (HttpURLConnection)url.openConnection(); conn.setRequestMethod("POST"); conn.setDoOutput(true); conn.setRequestProperty("Content-Type", "text/xml; charset="+ encoding); conn.setRequestProperty("Content-Length", String.valueOf(data.length)); conn.setConnectTimeout(5 * 1000); OutputStream outStream = conn.getOutputStream(); outStream.write(data); outStream.flush(); outStream.close(); if(conn.getResponseCode()==200){ return read2Byte(conn.getInputStream()); } return null; } //测试函数 public static void main(String args[]) throws Exception { Map<String, String> params = new HashMap<String, String>(); params.put("name", "xiazdong"); params.put("age", "10"); HttpURLConnection conn = (HttpURLConnection) HttpRequestUtil .sendGetRequest( "http://192.168.0.103:8080/Server/PrintServlet", params, null); int code = conn.getResponseCode(); InputStream in = conn.getInputStream(); byte[]data = read2Byte(in); }}测试代码：
Map<String,String> params = new HashMap<String,String>();params.put("name", name.getText().toString());params.put("age", age.getText().toString());HttpURLConnection conn = (HttpURLConnection) HttpRequestUtil.sendGetRequest("http://192.168.0.103:8080/Server/PrintServlet", params, null);文件上传测试代码：
FormFile formFile = new FormFile(file.getName(), file, "document", "text/plain");boolean isSuccess = HttpRequestUtil.uploadFile("http://192.168.0.103:8080/Server/FileServlet", null, formFile);简单了很多，对吧？