【JAVA】通过HttpClient发送HTTP请求的方法

时间:2023-05-16 22:36:20

HttpClient介绍

  HttpClient 不是一个浏览器。它是一个客户端的 HTTP 通信实现库。HttpClient的目标是发 送和接收HTTP 报文。HttpClient不会去缓存内容,执行 嵌入在 HTML 页面中的javascript 代码,猜测内容类型,重新格式化请求/重定向URI,或者其它和 HTTP 运输无关的功能。

HttpClient使用

  •   使用需要引入jar包,maven项目引入如下:
             <dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5</version>
    </dependency> <dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpcore</artifactId>
    <version>4.4.4</version>
    </dependency> <dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpmime</artifactId>
    <version>4.5</version>
    </dependency>
  •   使用方法,代码如下: 
     package com.test;
    
     import java.io.File;
    import java.io.IOException;
    import java.security.KeyManagementException;
    import java.security.KeyStoreException;
    import java.security.NoSuchAlgorithmException;
    import java.util.Iterator;
    import java.util.List;
    import java.util.Map; import org.apache.http.HttpEntity;
    import org.apache.http.HttpStatus;
    import org.apache.http.client.config.RequestConfig;
    import org.apache.http.client.methods.CloseableHttpResponse;
    import org.apache.http.client.methods.HttpGet;
    import org.apache.http.client.methods.HttpPost;
    import org.apache.http.config.Registry;
    import org.apache.http.config.RegistryBuilder;
    import org.apache.http.conn.socket.ConnectionSocketFactory;
    import org.apache.http.conn.socket.PlainConnectionSocketFactory;
    import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
    import org.apache.http.conn.ssl.SSLContextBuilder;
    import org.apache.http.conn.ssl.TrustSelfSignedStrategy;
    import org.apache.http.entity.ContentType;
    import org.apache.http.entity.StringEntity;
    import org.apache.http.entity.mime.MultipartEntityBuilder;
    import org.apache.http.entity.mime.content.FileBody;
    import org.apache.http.entity.mime.content.StringBody;
    import org.apache.http.impl.client.CloseableHttpClient;
    import org.apache.http.impl.client.DefaultHttpRequestRetryHandler;
    import org.apache.http.impl.client.HttpClients;
    import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
    import org.apache.http.util.EntityUtils; /**
    *
    * @author H__D
    * @date 2016年10月19日 上午11:27:25
    *
    */
    public class HttpClientUtil { // utf-8字符编码
    public static final String CHARSET_UTF_8 = "utf-8"; // HTTP内容类型。
    public static final String CONTENT_TYPE_TEXT_HTML = "text/xml"; // HTTP内容类型。相当于form表单的形式,提交数据
    public static final String CONTENT_TYPE_FORM_URL = "application/x-www-form-urlencoded"; // HTTP内容类型。相当于form表单的形式,提交数据
    public static final String CONTENT_TYPE_JSON_URL = "application/json;charset=utf-8"; // 连接管理器
    private static PoolingHttpClientConnectionManager pool; // 请求配置
    private static RequestConfig requestConfig; static { try {
    //System.out.println("初始化HttpClientTest~~~开始");
    SSLContextBuilder builder = new SSLContextBuilder();
    builder.loadTrustMaterial(null, new TrustSelfSignedStrategy());
    SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(
    builder.build());
    // 配置同时支持 HTTP 和 HTPPS
    Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory> create().register(
    "http", PlainConnectionSocketFactory.getSocketFactory()).register(
    "https", sslsf).build();
    // 初始化连接管理器
    pool = new PoolingHttpClientConnectionManager(
    socketFactoryRegistry);
    // 将最大连接数增加到200,实际项目最好从配置文件中读取这个值
    pool.setMaxTotal(200);
    // 设置最大路由
    pool.setDefaultMaxPerRoute(2);
    // 根据默认超时限制初始化requestConfig
    int socketTimeout = 10000;
    int connectTimeout = 10000;
    int connectionRequestTimeout = 10000;
    requestConfig = RequestConfig.custom().setConnectionRequestTimeout(
    connectionRequestTimeout).setSocketTimeout(socketTimeout).setConnectTimeout(
    connectTimeout).build(); //System.out.println("初始化HttpClientTest~~~结束");
    } catch (NoSuchAlgorithmException e) {
    e.printStackTrace();
    } catch (KeyStoreException e) {
    e.printStackTrace();
    } catch (KeyManagementException e) {
    e.printStackTrace();
    } // 设置请求超时时间
    requestConfig = RequestConfig.custom().setSocketTimeout(50000).setConnectTimeout(50000)
    .setConnectionRequestTimeout(50000).build();
    } public static CloseableHttpClient getHttpClient() { CloseableHttpClient httpClient = HttpClients.custom()
    // 设置连接池管理
    .setConnectionManager(pool)
    // 设置请求配置
    .setDefaultRequestConfig(requestConfig)
    // 设置重试次数
    .setRetryHandler(new DefaultHttpRequestRetryHandler(0, false))
    .build(); return httpClient;
    } /**
    * 发送Post请求
    *
    * @param httpPost
    * @return
    */
    private static String sendHttpPost(HttpPost httpPost) { CloseableHttpClient httpClient = null;
    CloseableHttpResponse response = null;
    // 响应内容
    String responseContent = null;
    try {
    // 创建默认的httpClient实例.
    httpClient = getHttpClient();
    // 配置请求信息
    httpPost.setConfig(requestConfig);
    // 执行请求
    response = httpClient.execute(httpPost);
    // 得到响应实例
    HttpEntity entity = response.getEntity(); // 可以获得响应头
    // Header[] headers = response.getHeaders(HttpHeaders.CONTENT_TYPE);
    // for (Header header : headers) {
    // System.out.println(header.getName());
    // } // 得到响应类型
    // System.out.println(ContentType.getOrDefault(response.getEntity()).getMimeType()); // 判断响应状态
    if (response.getStatusLine().getStatusCode() >= 300) {
    throw new Exception(
    "HTTP Request is not success, Response code is " + response.getStatusLine().getStatusCode());
    } if (HttpStatus.SC_OK == response.getStatusLine().getStatusCode()) {
    responseContent = EntityUtils.toString(entity, CHARSET_UTF_8);
    EntityUtils.consume(entity);
    } } catch (Exception e) {
    e.printStackTrace();
    } finally {
    try {
    // 释放资源
    if (response != null) {
    response.close();
    }
    } catch (IOException e) {
    e.printStackTrace();
    }
    }
    return responseContent;
    } /**
    * 发送Get请求
    *
    * @param httpGet
    * @return
    */
    private static String sendHttpGet(HttpGet httpGet) { CloseableHttpClient httpClient = null;
    CloseableHttpResponse response = null;
    // 响应内容
    String responseContent = null;
    try {
    // 创建默认的httpClient实例.
    httpClient = getHttpClient();
    // 配置请求信息
    httpGet.setConfig(requestConfig);
    // 执行请求
    response = httpClient.execute(httpGet);
    // 得到响应实例
    HttpEntity entity = response.getEntity(); // 可以获得响应头
    // Header[] headers = response.getHeaders(HttpHeaders.CONTENT_TYPE);
    // for (Header header : headers) {
    // System.out.println(header.getName());
    // } // 得到响应类型
    // System.out.println(ContentType.getOrDefault(response.getEntity()).getMimeType()); // 判断响应状态
    if (response.getStatusLine().getStatusCode() >= 300) {
    throw new Exception(
    "HTTP Request is not success, Response code is " + response.getStatusLine().getStatusCode());
    } if (HttpStatus.SC_OK == response.getStatusLine().getStatusCode()) {
    responseContent = EntityUtils.toString(entity, CHARSET_UTF_8);
    EntityUtils.consume(entity);
    } } catch (Exception e) {
    e.printStackTrace();
    } finally {
    try {
    // 释放资源
    if (response != null) {
    response.close();
    }
    } catch (IOException e) {
    e.printStackTrace();
    }
    }
    return responseContent;
    } /**
    * 发送 post请求
    *
    * @param httpUrl
    * 地址
    */
    public static String sendHttpPost(String httpUrl) {
    // 创建httpPost
    HttpPost httpPost = new HttpPost(httpUrl);
    return sendHttpPost(httpPost);
    } /**
    * 发送 get请求
    *
    * @param httpUrl
    */
    public static String sendHttpGet(String httpUrl) {
    // 创建get请求
    HttpGet httpGet = new HttpGet(httpUrl);
    return sendHttpGet(httpGet);
    } /**
    * 发送 post请求(带文件)
    *
    * @param httpUrl
    * 地址
    * @param maps
    * 参数
    * @param fileLists
    * 附件
    */
    public static String sendHttpPost(String httpUrl, Map<String, String> maps, List<File> fileLists) {
    HttpPost httpPost = new HttpPost(httpUrl);// 创建httpPost
    MultipartEntityBuilder meBuilder = MultipartEntityBuilder.create();
    if (maps != null) {
    for (String key : maps.keySet()) {
    meBuilder.addPart(key, new StringBody(maps.get(key), ContentType.TEXT_PLAIN));
    }
    }
    if (fileLists != null) {
    for (File file : fileLists) {
    FileBody fileBody = new FileBody(file);
    meBuilder.addPart("files", fileBody);
    }
    }
    HttpEntity reqEntity = meBuilder.build();
    httpPost.setEntity(reqEntity);
    return sendHttpPost(httpPost);
    } /**
    * 发送 post请求
    *
    * @param httpUrl
    * 地址
    * @param params
    * 参数(格式:key1=value1&key2=value2)
    *
    */
    public static String sendHttpPost(String httpUrl, String params) {
    HttpPost httpPost = new HttpPost(httpUrl);// 创建httpPost
    try {
    // 设置参数
    if (params != null && params.trim().length() > 0) {
    StringEntity stringEntity = new StringEntity(params, "UTF-8");
    stringEntity.setContentType(CONTENT_TYPE_FORM_URL);
    httpPost.setEntity(stringEntity);
    }
    } catch (Exception e) {
    e.printStackTrace();
    }
    return sendHttpPost(httpPost);
    } /**
    * 发送 post请求
    *
    * @param maps
    * 参数
    */
    public static String sendHttpPost(String httpUrl, Map<String, String> maps) {
    String parem = convertStringParamter(maps);
    return sendHttpPost(httpUrl, parem);
    } /**
    * 发送 post请求 发送json数据
    *
    * @param httpUrl
    * 地址
    * @param paramsJson
    * 参数(格式 json)
    *
    */
    public static String sendHttpPostJson(String httpUrl, String paramsJson) {
    HttpPost httpPost = new HttpPost(httpUrl);// 创建httpPost
    try {
    // 设置参数
    if (paramsJson != null && paramsJson.trim().length() > 0) {
    StringEntity stringEntity = new StringEntity(paramsJson, "UTF-8");
    stringEntity.setContentType(CONTENT_TYPE_JSON_URL);
    httpPost.setEntity(stringEntity);
    }
    } catch (Exception e) {
    e.printStackTrace();
    }
    return sendHttpPost(httpPost);
    } /**
    * 发送 post请求 发送xml数据
    *
    * @param httpUrl 地址
    * @param paramsXml 参数(格式 Xml)
    *
    */
    public static String sendHttpPostXml(String httpUrl, String paramsXml) {
    HttpPost httpPost = new HttpPost(httpUrl);// 创建httpPost
    try {
    // 设置参数
    if (paramsXml != null && paramsXml.trim().length() > 0) {
    StringEntity stringEntity = new StringEntity(paramsXml, "UTF-8");
    stringEntity.setContentType(CONTENT_TYPE_TEXT_HTML);
    httpPost.setEntity(stringEntity);
    }
    } catch (Exception e) {
    e.printStackTrace();
    }
    return sendHttpPost(httpPost);
    } /**
    * 将map集合的键值对转化成:key1=value1&key2=value2 的形式
    *
    * @param parameterMap
    * 需要转化的键值对集合
    * @return 字符串
    */
    public static String convertStringParamter(Map parameterMap) {
    StringBuffer parameterBuffer = new StringBuffer();
    if (parameterMap != null) {
    Iterator iterator = parameterMap.keySet().iterator();
    String key = null;
    String value = null;
    while (iterator.hasNext()) {
    key = (String) iterator.next();
    if (parameterMap.get(key) != null) {
    value = (String) parameterMap.get(key);
    } else {
    value = "";
    }
    parameterBuffer.append(key).append("=").append(value);
    if (iterator.hasNext()) {
    parameterBuffer.append("&");
    }
    }
    }
    return parameterBuffer.toString();
    } public static void main(String[] args) throws Exception { System.out.println(sendHttpGet("http://www.baidu.com")); }
    }