httpclient入门例子 demos

package com.test;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.KeyManagementException;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.util.ArrayList;
import java.util.List;

import javax.net.ssl.SSLContext;

import org.apache.http.HttpEntity;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.client.ClientProtocolException;
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.ssl.SSLConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLContexts;
import org.apache.http.conn.ssl.TrustSelfSignedStrategy;
import org.apache.http.entity.ContentType;
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.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.junit.Test;

public class HttpClientTest {

    @Test
    public void jUnitTest() {
        get();
    }

    /**
     * HttpClient连接SSL
     */
    public void ssl() {
        CloseableHttpClient httpclient = null;
        try {
            KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
            FileInputStream instream = new FileInputStream(new File("d:\tomcat.keystore"));
            try {
                // 加载keyStore d:\tomcat.keystore  
                trustStore.load(instream, "123456".toCharArray());
            } catch (CertificateException e) {
                e.printStackTrace();
            } finally {
                try {
                    instream.close();
                } catch (Exception ignore) {
                }
            }
            // 相信自己的CA和所有自签名的证书
            SSLContext sslcontext = SSLContexts.custom().loadTrustMaterial(trustStore, new TrustSelfSignedStrategy()).build();
            // 只允许使用TLSv1协议
            SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslcontext, new String[] { "TLSv1" }, null,
                    SSLConnectionSocketFactory.BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);
            httpclient = HttpClients.custom().setSSLSocketFactory(sslsf).build();
            // 创建http请求(get方式)
            HttpGet httpget = new HttpGet("https://localhost:8443/myDemo/Ajax/serivceJ.action");
            System.out.println("executing request" + httpget.getRequestLine());
            CloseableHttpResponse response = httpclient.execute(httpget);
            try {
                HttpEntity entity = response.getEntity();
                System.out.println("----------------------------------------");
                System.out.println(response.getStatusLine());
                if (entity != null) {
                    System.out.println("Response content length: " + entity.getContentLength());
                    System.out.println(EntityUtils.toString(entity));
                    EntityUtils.consume(entity);
                }
            } finally {
                response.close();
            }
        } catch (ParseException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (KeyManagementException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (KeyStoreException e) {
            e.printStackTrace();
        } finally {
            if (httpclient != null) {
                try {
                    httpclient.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    /**
     * post方式提交表单(模拟用户登录请求)
     */
    public void postForm() {
        // 创建默认的httpClient实例.  
        CloseableHttpClient httpclient = HttpClients.createDefault();
        // 创建httppost  
        HttpPost httppost = new HttpPost("http://localhost:8080/myDemo/Ajax/serivceJ.action");
        // 创建参数队列  
        List<namevaluepair> formparams = new ArrayList<namevaluepair>();
        formparams.add(new BasicNameValuePair("username", "admin"));
        formparams.add(new BasicNameValuePair("password", "123456"));
        UrlEncodedFormEntity uefEntity;
        try {
            uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8");
            httppost.setEntity(uefEntity);
            System.out.println("executing request " + httppost.getURI());
            CloseableHttpResponse response = httpclient.execute(httppost);
            try {
                HttpEntity entity = response.getEntity();
                if (entity != null) {
                    System.out.println("--------------------------------------");
                    System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8"));
                    System.out.println("--------------------------------------");
                }
            } finally {
                response.close();
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e1) {
            e1.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭连接,释放资源  
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 发送 post请求访问本地应用并根据传递参数不同返回不同结果
     */
    public void post() {
        // 创建默认的httpClient实例.  
        CloseableHttpClient httpclient = HttpClients.createDefault();
        // 创建httppost  
        HttpPost httppost = new HttpPost("http://localhost:8080/myDemo/Ajax/serivceJ.action");
        // 创建参数队列  
        List<namevaluepair> formparams = new ArrayList<namevaluepair>();
        formparams.add(new BasicNameValuePair("type", "house"));
        UrlEncodedFormEntity uefEntity;
        try {
            uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8");
            httppost.setEntity(uefEntity);
            System.out.println("executing request " + httppost.getURI());
            CloseableHttpResponse response = httpclient.execute(httppost);
            try {
                HttpEntity entity = response.getEntity();
                if (entity != null) {
                    System.out.println("--------------------------------------");
                    System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8"));
                    System.out.println("--------------------------------------");
                }
            } finally {
                response.close();
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e1) {
            e1.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭连接,释放资源  
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 发送 get请求
     */
    public void get() {
        CloseableHttpClient httpclient = HttpClients.createDefault();
        try {
            // 创建httpget.  
            HttpGet httpget = new HttpGet("http://www.baidu.com/");
            System.out.println("executing request " + httpget.getURI());
            // 执行get请求.  
            CloseableHttpResponse response = httpclient.execute(httpget);
            try {
                // 获取响应实体  
                HttpEntity entity = response.getEntity();
                System.out.println("--------------------------------------");
                // 打印响应状态  
                System.out.println(response.getStatusLine());
                if (entity != null) {
                    // 打印响应内容长度  
                    System.out.println("Response content length: " + entity.getContentLength());
                    // 打印响应内容  
                    System.out.println("Response content: " + EntityUtils.toString(entity));
                }
                System.out.println("------------------------------------");
            } finally {
                response.close();
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (ParseException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭连接,释放资源  
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 上传文件
     */
    public void upload() {
        CloseableHttpClient httpclient = HttpClients.createDefault();
        try {
            HttpPost httppost = new HttpPost("http://localhost:8080/myDemo/Ajax/serivceFile.action");

            FileBody bin = new FileBody(new File("F:\image\sendpix0.jpg"));
            StringBody comment = new StringBody("A binary file of some kind", ContentType.TEXT_PLAIN);

            HttpEntity reqEntity = MultipartEntityBuilder.create().addPart("bin", bin).addPart("comment", comment).build();

            httppost.setEntity(reqEntity);

            System.out.println("executing request " + httppost.getRequestLine());
            CloseableHttpResponse response = httpclient.execute(httppost);
            try {
                System.out.println("----------------------------------------");
                System.out.println(response.getStatusLine());
                HttpEntity resEntity = response.getEntity();
                if (resEntity != null) {
                    System.out.println("Response content length: " + resEntity.getContentLength());
                }
                EntityUtils.consume(resEntity);
            } finally {
                response.close();
            }
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}</namevaluepair></namevaluepair></namevaluepair></namevaluepair>
原文地址:https://www.cnblogs.com/blog-java/p/4531161.html