使用httpclient4上传文件

1.模拟form表单上传文件，主要是通过httpmime包中MultipartEntity对象，核心代码如下：

File file = new File(filePath);FileBody fb = new FileBody(file);MultipartEntity reqEntity = new MultipartEntity();reqEntity.addPart("myFile", fb);

2.以字节流的形式上传文件，主要通过FileEntity，核心代码如下：

File file = new File(filePath);FileEntity reqEntity = new FileEntity(file);postMethod.setEntity(reqEntity);

简单的demo程序：

package com.pengkw.client;import java.io.File;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import java.util.Map;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.NameValuePair;import org.apache.http.client.ClientProtocolException;import org.apache.http.client.HttpClient;import org.apache.http.client.entity.UrlEncodedFormEntity;import org.apache.http.client.methods.HttpGet;import org.apache.http.client.methods.HttpPost;import org.apache.http.entity.FileEntity;import org.apache.http.entity.mime.MultipartEntity;import org.apache.http.entity.mime.content.FileBody;import org.apache.http.entity.mime.content.StringBody;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.message.BasicNameValuePair;import org.apache.http.params.CoreConnectionPNames;import org.apache.http.util.EntityUtils;public class Client {/** * 读超时时间 */public static final int READ_TIME_OUT = 3000;/** * 连接超时时间 */public static final int CONNECTION_TIME_OUT = 3000;private HttpClient client;public Client(){init();}public void init(){this.client = new DefaultHttpClient();this.client.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, CONNECTION_TIME_OUT);this.client.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, READ_TIME_OUT);}public void get(String url){HttpGet getMethod = new HttpGet(url);try {HttpResponse response = client.execute(getMethod);HttpEntity entity = response.getEntity();System.out.println(response.getStatusLine().getStatusCode());System.out.println(EntityUtils.toString(entity));} catch (ClientProtocolException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {getMethod.releaseConnection();}}/** * 普通的post请求 * @param url * @param params */public void post(String url, Map<String, String> params){HttpPost postMethod = new HttpPost(url);try {if(params != null){List<NameValuePair> nvps = new ArrayList<NameValuePair>();Iterator<String> it = params.keySet().iterator();while(it.hasNext()){String name = it.next();nvps.add(new BasicNameValuePair(name, params.get(name)));}postMethod.setEntity(new UrlEncodedFormEntity(nvps));}HttpResponse response = client.execute(postMethod);HttpEntity entity = response.getEntity();System.out.println(response.getStatusLine().getStatusCode());System.out.println(EntityUtils.toString(entity));} catch (UnsupportedEncodingException e) {e.printStackTrace();} catch (ClientProtocolException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {postMethod.releaseConnection();}}/** * 模拟form表单上传 * @param url * @param filePath * @param params */public void uploadFileAsForm(String url, String filePath, Map<String, String> params){HttpPost postMethod = new HttpPost(url);try {File file = new File(filePath);FileBody fb = new FileBody(file);MultipartEntity reqEntity = new MultipartEntity();reqEntity.addPart("myFile", fb);if(params != null){Iterator<String> it = params.keySet().iterator();while(it.hasNext()){String name = it.next();reqEntity.addPart(name, new StringBody(params.get(name)));}}postMethod.setEntity(reqEntity);HttpResponse response = client.execute(postMethod);HttpEntity entity = response.getEntity();System.out.println(response.getStatusLine().getStatusCode());System.out.println(EntityUtils.toString(entity));} catch (ClientProtocolException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {postMethod.releaseConnection();}}/** * 以字节流的形式上传 * @param url * @param filePath */public void uploadFileAsStream(String url, String filePath){HttpPost postMethod = new HttpPost(url);File file = new File(filePath);FileEntity reqEntity = new FileEntity(file);postMethod.setEntity(reqEntity);try {HttpResponse response = client.execute(postMethod);HttpEntity entity = response.getEntity();System.out.println(response.getStatusLine().getStatusCode());System.out.println(EntityUtils.toString(entity));} catch (ClientProtocolException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} finally {postMethod.releaseConnection();}}/** * close http client */public void shutdown(){this.client.getConnectionManager().shutdown();}public static void main(String[] args) {Client client = new Client();client.get("http://www.baidu.com");client.shutdown();}}