使用 HttpClient 实现文件上传

package com.pinyougou.httpclient.login;

import org.apache.commons.httpclient.Cookie;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.cookie.CookiePolicy;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.util.EntityUtils;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

/**
 * Created by xiaohuihui on 2018-05-12
 */


public static void main(String[] args) {
    String respStr = null;

    // 1. 登录pinyougou,同时存入cookie
//  HttpClient httpClient = getCookie("http://localhost:9102/login");
    TestHttpClient testHttpClient = new TestHttpClient();
    CloseableHttpClient httpClient = null;
    try {
        httpClient = testHttpClient.testLogin();
    } catch (Exception e) {
        e.printStackTrace();
    }

    // 2. 使用HttpClient完成文件上传
//        String afterLoginUrl = "http://localhost:9102/itemCat/findByParentId.do?parentId=1";
//        afterLogin(httpClient, afterLoginUrl);

    // 3. 使用HttpClient完成文件上传
    String uploadUrl = "http://localhost:9102/upload.do";
    HttpPost httpPost = new HttpPost(uploadUrl);
    FileBody fileBody = new FileBody(new File("C:/Users/Administrator/Desktop/timg.jpg"));
    MultipartEntityBuilder multipartEntityBuilder = MultipartEntityBuilder.create();
    multipartEntityBuilder.addPart("file",fileBody);

    // 设置其他参数
    List<NameValuePair> nvps = new ArrayList<NameValuePair>();
    nvps.add(new NameValuePair("Accept","application/json, text/plain, */*"));
    nvps.add(new NameValuePair("Accept-Encoding","gzip, deflate, br"));
    nvps.add(new NameValuePair("Accept-Language","zh-CN,zh;q=0.9"));
    nvps.add(new NameValuePair("Connection","keep-alive"));
    nvps.add(new NameValuePair("Content-Length","28700"));
    nvps.add(new NameValuePair("Content-Type","multipart/form-data; boundary=----WebKitFormBoundarypaEfQmIQBbUrkI0c"));
    nvps.add(new NameValuePair("Host","localhost:9102"));
    nvps.add(new NameValuePair("Origin","http://localhost:9102"));
    nvps.add(new NameValuePair("Referer","http://localhost:9102/admin/goods_edit.html"));
    nvps.add(new NameValuePair("User-Agent","Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.146 Safari/537.36"));

    HttpEntity reqEntity  = multipartEntityBuilder.build();
    httpPost.setEntity(reqEntity);

    try {
        CloseableHttpResponse response = httpClient.execute(httpPost);
        System.out.println("上传之后返回的状态码:"+response.getStatusLine().getStatusCode());
        try {
            HttpEntity resEntity = response.getEntity();
            respStr = getRespString(resEntity);
            EntityUtils.consume(reqEntity);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
          response.close();
        }
    } catch (IOException e) {
        e.printStackTrace();
    }

    System.out.println("resp=" + respStr);


}


/**
 * 将返回结果转化为String
 *
 * @param entity
 * @return
 * @throws Exception
 */
private static String getRespString(HttpEntity entity) throws Exception {
    if (entity == null) {
        return null;
    }
    InputStream is = entity.getContent();
    StringBuffer strBuf = new StringBuffer();
    byte[] buffer = new byte[4096];
    int r = 0;
    while ((r = is.read(buffer)) > 0) {
        strBuf.append(new String(buffer, 0, r, "UTF-8"));
    }
    return strBuf.toString();
}

/**
 * 登陆后检测
 *
 * @param httpClient
 * @param afterLoginUrl
 */
private static void afterLogin(HttpClient httpClient, String afterLoginUrl) {
    // 进行登录后的操作
    GetMethod getMethod = new GetMethod(afterLoginUrl);
    try {
        httpClient.executeMethod(getMethod);
        // 打印出返回数据，检验一下是否成功
        String responseText = getMethod.getResponseBodyAsString();
        System.out.println(responseText);

    } catch (IOException e) {
        e.printStackTrace();
    }
}


/**
 * 使用HttpClient进行登录同时返回带有cookie信息的HttpClient对象
 * @param loginUrl
 * @return
 */
private static HttpClient getCookie(String loginUrl) {

//        String loginUrl = "http://localhost:9102/login";

    HttpClient httpClient = new HttpClient();
    // 使用post方式进行登录
    PostMethod postMethod = new PostMethod(loginUrl);
    // 设置登录信息
    NameValuePair[] data = {
            new NameValuePair("username", "wangyi"), new NameValuePair("password", "123456"),
            new NameValuePair("m1", "2")
    };

    postMethod.setRequestBody(data);

    // 设置 HttpClient 接收 Cookie,用与浏览器一样的策略
    httpClient.getParams().setCookiePolicy(CookiePolicy.BROWSER_COMPATIBILITY);
    try {
        httpClient.executeMethod(postMethod);
    } catch (IOException e) {
        e.printStackTrace();
    }
    // 获得登陆后的 Cookie
    Cookie[] cookies = httpClient.getState().getCookies();
    StringBuffer tmpcookies = new StringBuffer();
    for (Cookie c : cookies) {
        tmpcookies.append(c.toString() + ";");
    }

    return httpClient;
}

}

HttpClient4.x可以自带维持会话功能，只要使用同一个HttpClient且未关闭连接，则可以使用相同会话来访问其他要求登录验证的服务（见TestLogin()方法中的“执行get请求”部分）。
如果需要使用HttpClient池，并且想要做到一次登录的会话供多个HttpClient连接使用，就需要自己保存会话信息。因为客户端的会话信息是保存在cookie中的（JSESSIONID），所以只需要将登录成功返回的cookie复制到各个HttpClient使用即可。
使用Cookie的方法有两种，可以自己使用CookieStore来保存（见TestCookieStore()方法），也可以通过HttpClientContext上下文来维持（见TestContext()方法）。
附带HttpClient4.3示例代码 http://www.myexception.cn/program/1459749.html 。

package com.pinyougou.httpclient.login;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import org.apache.http.HeaderIterator;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.client.CookieStore;
import org.apache.http.client.config.CookieSpecs;
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.client.protocol.HttpClientContext;
import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.cookie.CookieSpecProvider;
import org.apache.http.impl.client.BasicCookieStore;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.cookie.BasicClientCookie;
import org.apache.http.impl.cookie.BestMatchSpecFactory;
import org.apache.http.impl.cookie.BrowserCompatSpecFactory;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.junit.Test;

/**
 * Created by xiaohuihui on 2018-05-12
 */
public class TestHttpClient {
// 创建CookieStore实例
static CookieStore cookieStore = null;
static HttpClientContext context = null;
String loginUrl = "http://localhost:9102/login";
String testUrl = "http://localhost:9102/itemCat/findByParentId.do?parentId=1";
String loginErrorUrl = "http://localhost:9102/login";

public CloseableHttpClient testLogin() throws Exception {
    System.out.println("----testLogin");

    // // 创建HttpClientBuilder
    // HttpClientBuilder httpClientBuilder = HttpClientBuilder.create();
    // // HttpClient
    // CloseableHttpClient client = httpClientBuilder.build();
    // 直接创建client
    CloseableHttpClient client = HttpClients.createDefault();

    HttpPost httpPost = new HttpPost(loginUrl);
    Map parameterMap = new HashMap();
    parameterMap.put("username", "wangyi");
    parameterMap.put("password", "123456");
    UrlEncodedFormEntity postEntity = new UrlEncodedFormEntity(
            getParam(parameterMap), "UTF-8");
    httpPost.setEntity(postEntity);
    System.out.println("request line:" + httpPost.getRequestLine());
    try {
        // 执行post请求
        HttpResponse httpResponse = client.execute(httpPost);
        String location = httpResponse.getFirstHeader("Location")
                .getValue();
        if (location != null && location.startsWith(loginErrorUrl)) {
            System.out.println("----loginError");
        }
        printResponse(httpResponse);

        // 执行get请求
        System.out.println("----the same client");
        HttpGet httpGet = new HttpGet(testUrl);
        System.out.println("request line:" + httpGet.getRequestLine());
        HttpResponse httpResponse1 = client.execute(httpGet);
        printResponse(httpResponse1);


        // cookie store
        setCookieStore(httpResponse);
        // context
        setContext();
        return client;

    } catch (IOException e) {
        e.printStackTrace();
        throw new RuntimeException(e);
    }
//        finally {
//            try {
//                // 关闭流并释放资源
//                client.close();
//            } catch (IOException e) {
//                e.printStackTrace();
//            }
//        }
}

@Test
public void testContext() throws Exception {
    System.out.println("----testContext");
    // 使用context方式
    CloseableHttpClient client = HttpClients.createDefault();
    HttpGet httpGet = new HttpGet(testUrl);
    System.out.println("request line:" + httpGet.getRequestLine());
    try {
        // 执行get请求
        HttpResponse httpResponse = client.execute(httpGet, context);
        printResponse(httpResponse);
        System.out.println("context cookies:"
                + context.getCookieStore().getCookies());
        printResponse(httpResponse);
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            // 关闭流并释放资源
            client.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

@Test
public void testCookieStore() throws Exception {
    System.out.println("----testCookieStore");
    // 使用cookieStore方式
    CloseableHttpClient client = HttpClients.custom()
            .setDefaultCookieStore(cookieStore).build();
    HttpGet httpGet = new HttpGet(testUrl);
    System.out.println("request line:" + httpGet.getRequestLine());
    try {
        // 执行get请求
        HttpResponse httpResponse = client.execute(httpGet);
        System.out.println("cookie store:" + cookieStore.getCookies());
        printResponse(httpResponse);
    } catch (IOException e) {
        e.printStackTrace();
    } finally {
        try {
            // 关闭流并释放资源
            client.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

public static void printResponse(HttpResponse httpResponse)
        throws ParseException, IOException {
    // 获取响应消息实体
    HttpEntity entity = httpResponse.getEntity();
    // 响应状态
    System.out.println("status:" + httpResponse.getStatusLine());
    System.out.println("headers:");
    HeaderIterator iterator = httpResponse.headerIterator();
    while (iterator.hasNext()) {
        System.out.println("\t" + iterator.next());
    }
    // 判断响应实体是否为空
    if (entity != null) {
        String responseString = EntityUtils.toString(entity);
        System.out.println("response length:" + responseString.length());
        System.out.println("response content:"
                + responseString.replace("\r\n", ""));
    }
}

public static void setContext() {
    System.out.println("----setContext");
    context = HttpClientContext.create();
    Registry<CookieSpecProvider> registry = RegistryBuilder
            .<CookieSpecProvider>create()
            .register(CookieSpecs.BEST_MATCH, new BestMatchSpecFactory())
            .register(CookieSpecs.BROWSER_COMPATIBILITY,
                    new BrowserCompatSpecFactory()).build();
    context.setCookieSpecRegistry(registry);
    context.setCookieStore(cookieStore);
}

public static void setCookieStore(HttpResponse httpResponse) {
    System.out.println("----setCookieStore");
    cookieStore = new BasicCookieStore();
    // JSESSIONID
    String setCookie = httpResponse.getFirstHeader("Set-Cookie")
            .getValue();
    String JSESSIONID = setCookie.substring("JSESSIONID=".length(),
            setCookie.indexOf(";"));
    System.out.println("JSESSIONID:" + JSESSIONID);
    // 新建一个Cookie
    BasicClientCookie cookie = new BasicClientCookie("JSESSIONID",
            JSESSIONID);
    cookie.setVersion(0);
    cookie.setDomain("127.0.0.1");
    cookie.setPath("/CwlProClient");
    // cookie.setAttribute(ClientCookie.VERSION_ATTR, "0");
    // cookie.setAttribute(ClientCookie.DOMAIN_ATTR, "127.0.0.1");
    // cookie.setAttribute(ClientCookie.PORT_ATTR, "8080");
    // cookie.setAttribute(ClientCookie.PATH_ATTR, "/CwlProWeb");
    cookieStore.addCookie(cookie);
}

public static List<NameValuePair> getParam(Map parameterMap) {
    List<NameValuePair> param = new ArrayList<NameValuePair>();
    Iterator it = parameterMap.entrySet().iterator();
    while (it.hasNext()) {
        Entry parmEntry = (Entry) it.next();
        param.add(new BasicNameValuePair((String) parmEntry.getKey(),
                (String) parmEntry.getValue()));
    }
    return param;
}


}