URLConnection 和 HttpClients 发送请求范例

笔记，未完全标准.

java.net.URLConnection

package test;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.OutputStreamWriter;

import java.io.PrintWriter;

import java.net.URL;

import java.net.URLConnection;

public class Test {

    public static void main(String[] args) throws Exception{

        try {

            //String info=HttpTool.sendRequestData("searchArg=宝马740", "http://localhost:8080/vhl/VhlSearch.act", new Long(300000));

            String info=invoke("vhlName=大众","http://localhost:8080/vhl/vhlSearch.html");

            System.out.println("接收到的车辆信息："+info);

        } catch (IOException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }

private static String invoke(String param, String url) throws Exception {

        PrintWriter out = null;

        BufferedReader in = null;

        String result = "";

        try {

            URL realUrl = new URL(url);

            // 打开和URL之间的连接

            URLConnection conn = realUrl.openConnection();

            // 设置通用的请求属性

            conn.setRequestProperty("vhlsinfo", "<?xml version=\"1.0\" encoding=\"UTF-8\" ?> <PACKET><TOTAL>哈哈</TOTAL> <VHL_LIST /></PACKET>");

            conn.setRequestProperty("accept", "*/*");

            conn.setRequestProperty("connection", "Keep-Alive");

            conn.setRequestProperty("user-agent","Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");

            // 发送POST请求必须设置如下两行

            conn.setDoOutput(true);

            conn.setDoInput(true);

            // 获取URLConnection对象对应的输出流

            out = new PrintWriter(new OutputStreamWriter(conn.getOutputStream(),"UTF-8"));//请求编码设置

            // 发送请求参数

            out.print(param);

            // flush输出流的缓冲

            out.flush();

            // 定义BufferedReader输入流来读取URL的响应

            in = new BufferedReader(new InputStreamReader(conn.getInputStream(),"UTF-8"));//返回编码设置

            String line;

            while ((line = in.readLine()) != null) {

                result += line;

            }

        } catch (Exception e) {

            System.out.println("发送 POST 请求出现异常！" + e);

            e.printStackTrace();

        }

        // 使用finally块来关闭输出流、输入流

        finally {

            try {

                if (out != null) {

                    out.close();

                }

                if (in != null) {

                    in.close();

                }

            } catch (IOException ex) {

                ex.printStackTrace();

            }

        }

        return result;

    }

}

.

org.apache.http.impl.client.HttpClients

package com.testdemo.validate.tool;

import java.io.IOException;

import org.apache.http.HttpEntity;

import org.apache.http.HttpResponse;

import org.apache.http.client.ClientProtocolException;

import org.apache.http.client.ResponseHandler;

import org.apache.http.client.entity.EntityBuilder;

import org.apache.http.client.methods.HttpPost;

import org.apache.http.entity.ContentType;

import org.apache.http.impl.client.CloseableHttpClient;

import org.apache.http.impl.client.HttpClients;

import org.apache.http.util.EntityUtils;

public class ESB {

    public static String invoke(String paramStr,String url,String systemName) throws Exception{

        CloseableHttpClient httpclient = null;

        String response = null;

        httpclient = HttpClients.custom().build();

        HttpPost httppost = new HttpPost(url);

        HttpEntity reqEntity = EntityBuilder.create()

        .setContentType(ContentType.APPLICATION_JSON)

        .setContentEncoding("UTF-8")

        .setText(paramStr)

        .build();

        httppost.setEntity(reqEntity);

        httppost.setHeader("userName", systemName);//在head中设置属性,后台服务端提取系统名

        try {

            response = httpclient.execute(httppost,

                    new ResponseHandler<String>() {

                        // 处理响应

                        @Override

                        public String handleResponse(final HttpResponse response) throws ClientProtocolException, IOException {

                            String responseJson = null;

                            HttpEntity entity = null;

                            int status = response.getStatusLine().getStatusCode();

                            if (status >= 200 && status < 300) {

                                entity = response.getEntity();

                                if (entity != null) {

                                    String sentity = EntityUtils.toString(entity, "UTF-8");

                                    if (sentity == null|| sentity.trim().length() == 0)

                                        return null;

                                    responseJson = sentity;

                                    //write(responseJson);

                                } else {

                                    responseJson = response.getStatusLine().getReasonPhrase()+ "  返回的结果为空！";

                                }

                            } else {

                                responseJson = response.getStatusLine().toString();

                            }

                            //System.out.println(responseJson);

                            return responseJson;

                        }

                    });

        } catch (Exception e) {

            e.printStackTrace();

            throw e;

        } finally {

            // 5. 释放连接

            httppost.releaseConnection();

            httpclient.close();

        }

        return response;

    }

    public static void main(String[] args) throws Exception{

        String systemName = "echannel";

        System.out.print(invoke("VHL_NAME=马自达&RET_TYPE=json","http://192.168.1.2:8012/vhl/vhlSearch.do",null));

//        System.out.print(invoke("VHL_NAME=马自达&RET_TYPE=json","http://localhost:8080/vhl/vhlSearch.do",systemName));

    }

}