综合数据api接口使用

由于请求数据接口是跨域的，但是我们无法改变接口的代码

先从请求后台，然后从后台进行二次请求，请求数据接口

原生代码

package edu.nf.http.test;

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.methods.RequestBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.junit.Test;

import java.io.IOException;

/**
 * @Author Eric
 * @Date 2018/12/10
 */
public class HttpClientTest {
    @Test
    public void testGet(){
        //创建一个HttpClient对象，用于发送请求和接收响应信息
        CloseableHttpClient client = HttpClients.createDefault();
        //创建请求构建起（工厂）
        RequestBuilder builder = RequestBuilder.get();
        //设置请求的uri
        builder.setUri("http://c.3g.163.com/nc/article/list/T1348647853363/0-40.html");
        //创建一个get请求对象
        HttpUriRequest request = builder.build();
        //发送请求，并返回响应对象
        try {
            CloseableHttpResponse response = client.execute(request);
            //从响应对象中获取数据，这里使用了一个HttpEntity封装
            HttpEntity entity = response.getEntity();
            //从Entity中获取真正的响应内容
            String json = EntityUtils.toString(entity);
            System.out.println(json);
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException(e.getMessage());
        }
    }
    @Test
    public void testPost(){
        //创建一个HttpClient对象，用于发送请求和接收响应信息
        CloseableHttpClient client = HttpClients.createDefault();
        RequestBuilder builder = RequestBuilder.post();
        builder.setUri("http://c.3g.163.com/nc/article/list/T1348647853363/0-40.html");
        //可以提交参数
        builder.addParameter("user","admin").addParameter("age","18");
        //构建请求对象
        HttpUriRequest request = builder.build();
        //发送请求
        try {
            CloseableHttpResponse response = client.execute(request);
            //获取响应数据
            HttpEntity entity = response.getEntity();
            String json = EntityUtils.toString(entity);
            System.out.println(json);
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException(e.getMessage());
        }
    }
}

封装成工具类

package edu.nf.http.conmmons;

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.methods.RequestBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

import java.io.IOException;
import java.util.Map;

/**
 * @Author Eric
 * @Date 2018/12/10
 * 封装工具类
 */
public class HttpUtils {
    /**
     * 创建一个唯一的client对象
     */
    private static CloseableHttpClient client = HttpClients.createDefault();

    /**
     * 发送get请求
     * @param uri
     * @return
     */
    public static String get(String uri){
        //构建get请求
        HttpUriRequest request = RequestBuilder.get(uri).build();
        return execute(request);
    }

    /**
     * 发送post请求
     * @param uri
     * @param params post所提交的参数
     * @return
     */
    public static String post(String uri, Map<String,String>params){
        RequestBuilder builder = RequestBuilder.post(uri);
        //循环设置参数
        for (String name : params.keySet()) {
            builder.addParameter(name,params.get(name));
        }
        HttpUriRequest request = builder.build();
        return execute(request);
    }

    /**
     * 发送请求并返回响应内容
     * @param request
     * @return
     */
    private static String execute(HttpUriRequest request){
        try {
            //发送请求
            CloseableHttpResponse response = client.execute(request);
            HttpEntity entity = response.getEntity();
            return EntityUtils.toString(entity);
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException(e.getMessage());
        }
    }
}

json序列化工具类

（获取到的数据是字符串，序列化成json）

package edu.nf.http.conmmons;

import com.fasterxml.jackson.databind.ObjectMapper;

import java.io.IOException;

/**
 * @Author Eric
 * @Date 2018/12/10
 */
public class JsonUtils {
    public static<T> T convert(String json,Class<T> clazz){
        ObjectMapper mapper = new ObjectMapper();
        try {
            return mapper.readValue(json,clazz);
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException(e.getMessage());
        }
    }
}

Service过滤

package edu.nf.http.service;

import edu.nf.http.conmmons.HttpUtils;
import edu.nf.http.conmmons.JsonUtils;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Map;

/**
 * @Author Eric
 * @Date 2018/12/10
 */
@Service
public class NewsService {
    public List<Map<String,Object>> listNews(){
        String json = HttpUtils.get("http://c.3g.163.com/nc/article/list/T1348647853363/0-40.html");
        //将json转换成Map对象
        Map<String,List<Map<String,Object>>> map = JsonUtils.convert(json,Map.class);
        //进行数据清洗（过滤）
        List<Map<String,Object>>list = map.get("T1348647853363");
        //删除头行没用的数据
        list.remove(0);
        return list;
    }

    public static void main(String[] args) {
        List<Map<String,Object>>list = new NewsService().listNews();
        System.out.println(list.size());
    }
}

ResponseVO

package edu.nf.http.controller.vo;

/**
 * @Author Eric
 * @Date 2018/12/6
 */
public class ResponseVO<T> {
    private Integer code;
    private String message;
    private T data;

    @Override
    public String toString() {
        return "ResponseVO{" +
                "code=" + code +
                ", message='" + message + '\'' +
                ", data=" + data +
                '}';
    }

    public Integer getCode() {
        return code;
    }

    public void setCode(Integer code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public T getData() {
        return data;
    }

    public void setData(T data) {
        this.data = data;
    }
}

Controller

package edu.nf.http.controller;

import edu.nf.http.controller.vo.ResponseVO;
import edu.nf.http.service.NewsService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;
import java.util.Map;

/**
 * @Author Eric
 * @Date 2018/12/10
 */
@RestController
public class NewsController {
    @Autowired
    private NewsService newsService;
    @GetMapping("/listNews")
    public ResponseVO listNews(){
        ResponseVO vo = new ResponseVO();
        List<Map<String,Object>> list = newsService.listNews();
        vo.setCode(HttpStatus.OK.value());
        vo.setMessage("无数据");
        vo.setData(list);
        return vo;
    }
}

HTML

(使用Postman工具进行请求可以查看返回的字段，在页面可以用对象进行输出)

<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <title>新闻头条</title>
    </head>
    <body>
        <header class="bar bar-nav">
          <h1 class="title">今日头条</h1>
        </header>
        <div class="content">
          <div class="content-block-title">简单列表</div>
          <div class="list-block media-list">
            <ul id="news_id">
              <li>
                <div class="item-content">
                  <div class="item-media"><img src="http://gqianniu.alicdn.com/bao/uploaded/i4//tfscom/i3/TB10LfcHFXXXXXKXpXXXXXXXXXX_!!0-item_pic.jpg_250x250q60.jpg" style='width: 2.2rem;'></div>
                  <div class="item-inner">
                    <div class="item-title-row">
                      <div class="item-title">标题</div>
                    </div>
                    <div class="item-subtitle">子标题</div>
                  </div>
                </div>
              </li>
            </ul>
          </div>
        </div>
        <link rel="stylesheet" href="//g.alicdn.com/msui/sm/0.6.2/css/sm.min.css">
        <script type='text/javascript' src='//g.alicdn.com/sj/lib/zepto/zepto.min.js' charset='utf-8'></script>
        <script type='text/javascript' src='//g.alicdn.com/msui/sm/0.6.2/js/sm.min.js' charset='utf-8'></script>
        <script>
            $(function(){
                $.ajax({
                    type:"get",
                    url:"http://localhost:8080/listNews",
                    success:function(result){
                        $.each(result.data, function(index,news) {
                            $("#news_id").append(
                                "<li>"+
                                    "<div class='item-content'>"+
                                          "<div class='item-media'><img src='"+news.imgsrc+"'  style='width: 2.2rem;'></div>"+
                                              "<div class='item-inner'>"+
                                                "<div class='item-title-row'>"+
                                                  "<div class='item-title'>"+news.source+"</div>"+
                                                "</div>"+
                                            "<div class='item-subtitle'>"+news.title+"</div>"+
                                          "</div>"+
                                    "</div>"+
                                  "</li>"
                            );
                        });
                    }

                });
            });
        </script>
    </body>
</html>