httpclient的使用

Posted 2021-02-19 mr-k404

最近工作中经常调用第三方接口，选择使用了httpclient,简单记录下代码的实现过程
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import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URL;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

import org.apache.http.Consts;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.entity.UrlEncodedFormEntity;
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.conn.scheme.Scheme;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.conn.ssl.X509HostnameVerifier;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.alibaba.fastjson.JSONObject;

/**

• http请求的工具类
  /
  public class HttpClientUtil {
  private static final Logger log = LoggerFactory.getLogger(HttpClientUtil.class);
  /*

  • 初始化HttpClient
    */
    private CloseableHttpClient httpClient = HttpClients.createDefault();

  /**

  • POST方式调用
  • @param url
  • @param params 参数为NameValuePair键值对对象
  • @return 响应字符串
  • @throws java.io.UnsupportedEncodingException
    */
    public String executeByPOST(String url, List params) {
    HttpPost post = new HttpPost(url);
    ResponseHandler responseHandler = new BasicResponseHandler();
    String responseJson = null;
    try {
    if (params != null) {
    post.setEntity(new UrlEncodedFormEntity(params));
    }
    responseJson = httpClient.execute(post, responseHandler);
    log.info("HttpClient POST请求结果：" + responseJson);
    }
    catch (ClientProtocolException e) {
    e.printStackTrace();
    log.info("HttpClient POST请求异常：" + e.getMessage());
    }
    catch (IOException e) {
    e.printStackTrace();
    }
    finally {
    httpClient.getConnectionManager().closeExpiredConnections();
    httpClient.getConnectionManager().closeIdleConnections(30, TimeUnit.SECONDS);
    }
    return responseJson;
    }

  /**

  • Get方式请求
  • @param url 带参数占位符的URL，例：http://ip/User/user/center.aspx?_action=GetSimpleUserInfo&codes={0}&email={1}
  • @param params 参数值数组，需要与url中占位符顺序对应
  • @return 响应字符串
  • @throws java.io.UnsupportedEncodingException
    */
    public String executeByGET(String url, Object[] params) {
    String messages = MessageFormat.format(url, params);
    HttpGet get = new HttpGet(messages);
    ResponseHandler responseHandler = new BasicResponseHandler();
    String responseJson = null;
    try {
    responseJson = httpClient.execute(get, responseHandler);
    log.info("HttpClient GET请求结果：" + responseJson);
    }
    catch (ClientProtocolException e) {
    e.printStackTrace();
    log.error("HttpClient GET请求异常：" + e.getMessage());
    }
    catch (IOException e) {
    e.printStackTrace();
    log.error("HttpClient GET请求异常：" + e.getMessage());
    }
    finally {
    httpClient.getConnectionManager().closeExpiredConnections();
    httpClient.getConnectionManager().closeIdleConnections(30, TimeUnit.SECONDS);
    }
    return responseJson;
    }

  /**

  • @param url
  • @return
    */
    public String executeByGET(String url) {
    HttpGet get = new HttpGet(url);
    ResponseHandler responseHandler = new BasicResponseHandler();
    String responseJson = null;
    try {
    responseJson = httpClient.execute(get, responseHandler);
    log.info("HttpClient GET请求结果：" + responseJson);
    }
    catch (ClientProtocolException e) {
    e.printStackTrace();
    log.error("HttpClient GET请求异常：" + e.getMessage());
    }
    catch (IOException e) {
    e.printStackTrace();
    log.error("HttpClient GET请求异常：" + e.getMessage());
    }
    finally {
    httpClient.getConnectionManager().closeExpiredConnections();
    httpClient.getConnectionManager().closeIdleConnections(30, TimeUnit.SECONDS);
    }
    return responseJson;
    }

  /**

  • https posp请求，可以绕过证书校验
  • @param url
  • @param params
  • @return
    */
    public static final String sendHttpsRequestByPost(String url, Map<String, String> params) {
    String responseContent = null;
    HttpClient httpClient = new DefaultHttpClient();
    //创建TrustManager
    X509TrustManager xtm = new X509TrustManager() {
    public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {}
    public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {}
    public X509Certificate[] getAcceptedIssuers() {
    return null;
    }
    };

//这个好像是HOST验证
X509HostnameVerifier hostnameVerifier = new X509HostnameVerifier() {
public boolean verify(String arg0, SSLSession arg1) {
return true;
}
public void verify(String arg0, SSLSocket arg1) throws IOException {}
public void verify(String arg0, String[] arg1, String[] arg2) throws SSLException {}
public void verify(String arg0, X509Certificate arg1) throws SSLException {}
};
try {
//TLS1.0与SSL3.0基本上没有太大的差别，可粗略理解为TLS是SSL的继承者，但它们使用的是相同的SSLContext
SSLContext ctx = SSLContext.getInstance("TLS");
//使用TrustManager来初始化该上下文，TrustManager只是被SSL的Socket所使用
ctx.init(null, new TrustManager[] { xtm }, null);
//创建SSLSocketFactory
SSLSocketFactory socketFactory = new SSLSocketFactory(ctx);
socketFactory.setHostnameVerifier(hostnameVerifier);
//通过SchemeRegistry将SSLSocketFactory注册到我们的HttpClient上
httpClient.getConnectionManager().getSchemeRegistry().register(new Scheme("https", socketFactory, 443));
HttpPost httpPost = new HttpPost(url);
List formParams = new ArrayList(); // 构建POST请求的表单参数
for (Map.Entry<String, String> entry : params.entrySet()) {
formParams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
}
httpPost.setEntity(new UrlEncodedFormEntity(formParams, "UTF-8"));
HttpResponse response = httpClient.execute(httpPost);
HttpEntity entity = response.getEntity(); // 获取响应实体
if (entity != null) {
responseContent = EntityUtils.toString(entity, "UTF-8");
}
} catch (KeyManagementException e) {
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (ParseException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
// 关闭连接,释放资源
httpClient.getConnectionManager().shutdown();
}
return responseContent;
}
/**

• 发送HTTP_POST请求,json格式数据
• @param url
• @param body
• @return
• @throws Exception
  /
  public static String sendPostByJson(String url, String body,String token) throws Exception {
  CloseableHttpClient httpclient = HttpClients.custom().build();
  HttpPost post = null;
  String resData = null;
  CloseableHttpResponse result = null;
  try {
  post = new HttpPost(url);
  HttpEntity entity2 = new StringEntity(body, Consts.UTF_8);
  post.setConfig(RequestConfig.custom().setConnectTimeout(30000).setSocketTimeout(30000).build());
  post.setHeader("Content-Type", "application/json");
  post.setHeader("Authorization","bearer "+token);
  post.setEntity(entity2);
  result = httpclient.execute(post);
  if (HttpStatus.SC_OK == result.getStatusLine().getStatusCode()) {
  resData = EntityUtils.toString(result.getEntity());
  }
  } finally {
  if (result != null) {
  result.close();
  }
  if (post != null) {
  post.releaseConnection();
  }
  httpclient.close();
  }
  return resData;
  }
  public static String sendPostByJson(String url, String body) throws Exception {
  CloseableHttpClient httpclient = HttpClients.custom().build();
  HttpPost post = null;
  String resData = null;
  CloseableHttpResponse result = null;
  try {
  post = new HttpPost(url);
  HttpEntity entity2 = new StringEntity(body, Consts.UTF_8);
  post.setConfig(RequestConfig.custom().setConnectTimeout(30000).setSocketTimeout(30000).build());
  post.setHeader("Content-Type", "application/json");
  post.setEntity(entity2);
  result = httpclient.execute(post);
  if (HttpStatus.SC_OK == result.getStatusLine().getStatusCode()) {
  resData = EntityUtils.toString(result.getEntity());
  }
  } finally {
  if (result != null) {
  result.close();
  }
  if (post != null) {
  post.releaseConnection();
  }
  httpclient.close();
  }
  return resData;
  }
  /*
• 发送HTTP_GET请求
• @see 该方法会自动关闭连接,释放资源
• @param requestURL 请求地址(含参数)
• @param decodeCharset 解码字符集,解析响应数据时用之,其为null时默认采用UTF-8解码
• @return 远程主机响应正文
  */
  public static String sendGetRequest(String reqURL, String decodeCharset){
  long responseLength = 0; //响应长度
  String responseContent = null; //响应内容
  HttpClient httpClient = new DefaultHttpClient(); //创建默认的httpClient实例
  HttpGet httpGet = new HttpGet(reqURL); //创建org.apache.http.client.methods.HttpGet
  try{
  HttpResponse response = httpClient.execute(httpGet); //执行GET请求
  HttpEntity entity = response.getEntity(); //获取响应实体
  if(null != entity){
  responseLength = entity.getContentLength();
  responseContent = EntityUtils.toString(entity, decodeCharset==null ? "UTF-8" : decodeCharset);
  EntityUtils.consume(entity); //Consume response content
  }
  System.out.println("请求地址: " + httpGet.getURI());
  System.out.println("响应状态: " + response.getStatusLine());
  System.out.println("响应长度: " + responseLength);
  System.out.println("响应内容: " + responseContent);
  }catch(ClientProtocolException e){
  log.debug("该异常通常是协议错误导致,比如构造HttpGet对象时传入的协议不对(将‘http‘写成‘htp‘)或者服务器端返回的内容不符合HTTP协议要求等,堆栈信息如下", e);
  }catch(ParseException e){
  log.debug(e.getMessage(), e);
  }catch(IOException e){
  log.debug("该异常通常是网络原因引起的,如HTTP服务器未启动等,堆栈信息如下", e);
  }finally{
  httpClient.getConnectionManager().shutdown(); //关闭连接,释放资源
  }
  return responseContent;
  }

}
`