Java如何调用接口API并返回数据（两种方法）
java处理请求接口后返回的json数据-直接处理json字符串
处理思路：
将返回的数据接收到一个String对象中（有时候需要自己选择性的取舍接收）
再将string转换为JSONObject对象
用get（）方法获取到对应的值
注意：基于第三点的特殊情况，如果返回的json里面出现多组数据的情况，则需要转换为数据（用JSONObject.parseArrat()转换再进行操作 ，可无限套娃）
调用接口，请求数据
1.post方法
import com.alibaba.fastjson.JSONObject;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
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.client.utils.URIBuilder;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
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.springframework.beans.factory.annotation.Autowired;
import java.io.IOException;
import java.net.URI;
import java.util.*;
public static JSONObject postResponse(String url,JSONObject jsonParam){
HttpClient client = HttpClients.createDefault();
// 要调用的接口方法
HttpPost post = new HttpPost(url);
JSONObject jsonObject = null;
try {
StringEntity s = new StringEntity(jsonParam.toString(),"UTF-8");
s.setContentType("application/json");
post.setEntity(s);
post.setHeader("Content-Type","application/json");
HttpResponse res = client.execute(post);
if(res.getStatusLine().getStatusCode() == HttpStatus.SC_OK){
/*返回json格式*/
jsonObject = JSONObject.parseObject(EntityUtils.toString(res.getEntity()));
}
} catch (IOException e) {
System.out.println("接口调用出错！");
e.printStackTrace();
throw new RuntimeException(e);
}
return jsonObject;
}
2.get方法
import com.alibaba.fastjson.JSONObject;
import edu.zhku.fire_ant_project.config.WxConstant;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
public class HttpCallOtherInterfaceUtils {
public static void main(String args[]) {
HttpClient client = HttpClients.createDefault();
// 要调用的接口方法
String url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid="+ WxConstant.appid +"&secret="+WxConstant.secret;
HttpGet httpGet=new HttpGet(url);
JSONObject jsonObject = null;
try {
HttpResponse res = client.execute(httpGet);
if (res.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
// 返回json格式：
jsonObject = JSONObject.parseObject(EntityUtils.toString(res.getEntity()));
System.out.println(jsonObject);
}
} catch (Exception e) {
System.out.println("服务间接口调用出错！");
e.printStackTrace();
}
}
}
处理返回后的json数据
参考代码：
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
public class JsonStr {
public static void main(String[] args) {
//1.比如从前端接收的是这个样子的json字符串,但是我们是不能直接获取到经度 纬度所对应的值的，所以必须要对这个字符串进行解析，
String str = "{\"code\":\"0\"," +
"\"error\":null," +
"\"msg\":\"success\"," +
"\"detail\":[\n" +
" {\"phoneNum\":\"013012401091\",\n" +
" \"lat\":34.431864,\n" +
" \"lon\":109.25992,\n" +
" \"height\":360,\n" +
" \"speed\":33,\n" +
" \"direction\":10,\n" +
" \"gpsTime\":1615420800000,\n" +
" \"gpsDateTime\":1615420800000,\n" +
" \"mileage\":253830800,\n" +
" \"alarms\":[24],\n" +
" \"status\":[1,2,21],\n" +
" \"property\":{}\n" +
" }" +
" ]" +
" }";
//先转换成JSONObject类型
JSONObject jsonObj = JSON.parseObject(str);
//通过JSONObject中的getString("key")方法，得到对应的值 {"code":"0","error":null,"msg":"success"}这种类型
System.out.println("code："+jsonObj.getString("code"));
//2.字符串中含有数组的，比如像detail中的数据
JSONArray jsonInfo = JSONObject.parseArray(jsonObj.getString("detail"));//将jsonObj解析成json数组
for (int i = 0; i < jsonInfo.size(); i++) {//遍历detail信息
JSONObject jsonDetailInfo = jsonInfo.getJSONObject(i);//根据下标以此拿数据，每一个数据又是一个JSONObject对象，所以用JSONObject接收
String lat = jsonDetailInfo.getString("lat");
String lon = jsonDetailInfo.getString("lon");
String gpsDateTime = jsonDetailInfo.getString("gpsDateTime");
//然后进行其他处理
System.out.println("lat："+lat+";lon:"+lon+";gpsDateTime："+gpsDateTime);
}
}
}
例子： 请求数据要求分页 所以采取循环
返回值说明：
{
"code": "200",
"data": {
"endRow": 2,
"firstPage": 1,
"hasNextPage": true,
"hasPreviousPage": false,
"isFirstPage": true,
"isLastPage": false,
"lastPage": 8,
"list": [
{
"packingUnit": "盒", //包装单位
"factory": "河北百善药业有限公司", //生产企业
"salePrice": 11.7, //销售价
"fullSalePrice": 11.5, //整件销售价
"inventoryQuantity": 172, //库存
"pictureUrl": "/upload/product/pic/2021/11/20101013-2-424389.png", //商品图片
"policyTitle": "10盒起积0.5分/盒，20盒起积1分/盒",//商品政策：比如10盒积1分意思是10盒每盒减1元，10s5：表示买10盒送5盒
"policyStartDate": "2022-11-01",//商品政策开始日期
"policyEndDate": "2022-11-30",//商品政策结束日期
"validDateStr": "2024-09-07",//最近批号有效期
"batchNumber": "2207012", //最近批号
"registerFileUrl": "https://img.zc511.com/data/uploadRegisterFileOne.shtml?productCode=20101013-2", // 注册资料下载URL
"authorizeNumber": "国药准字Z20063720",
"rowId": 1,
"barCode": "6909557000263",//商品条码
"parseProductName": "接骨片",//商品名称
"productCode": "20101013-2",//商品条码
"countryCode": "ZG01AAJ0247010302685",//国家码 医保码
"packingAmount": 200,//大包装
"parseProductSpec": "60片",//规格
"retailPrice": 196,//市场零售价
"minPackingNumber": 0//最小购买包装
}
],
"navigatePages": 8,
"navigatepageNums": [
1,
2,
3,
4,
5,
6,
7,
8
],
"nextPage": 2,
"pageNum": 1,
"pageSize": 2,
"pages": 5627,
"prePage": 0,
"size": 2,
"startRow": 1,
"total": 11254
},
"msg": "",
"success": true
}
HttpCilentutil
请求接口数据
import com.alibaba.fastjson.JSONObject;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
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.client.utils.URIBuilder;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
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.springframework.beans.factory.annotation.Autowired;
import java.io.IOException;
import java.net.URI;
import java.util.*;
public class HttpClientUtil
{
public static JSONObject postResponse(String url,JSONObject jsonParam){
HttpClient client = HttpClients.createDefault();
// 要调用的接口方法
HttpPost post = new HttpPost(url);
JSONObject jsonObject = null;
try {
StringEntity s = new StringEntity(jsonParam.toString(),"UTF-8");
s.setContentType("application/json");
post.setEntity(s);
post.setHeader("Content-Type","application/json");
HttpResponse res = client.execute(post);
if(res.getStatusLine().getStatusCode() == HttpStatus.SC_OK){
/*返回json格式*/
jsonObject = JSONObject.parseObject(EntityUtils.toString(res.getEntity()));
}
} catch (IOException e) {
System.out.println("接口调用出错！");
e.printStackTrace();
throw new RuntimeException(e);
}
return jsonObject;
}
//请求一次接口 先获取分页后的总数据
public static Map<String,Object> getOneRequest(){
String url ="http://gateway.zc511.com/getway/v2/product_list_get.shtml";
JSONObject params = new JSONObject();
params.put("timestamp","1650865510301");
params.put("appKey","ZBKJ");
params.put("secret","123");
params.put("sign","1186D2A92FC3AB4E5671EBF58B9896A6");
params.put("buyerCode","3330020298-1");
params.put("pageNum","1");
params.put("pageSize","2000");
JSONObject jsonObject = HttpClientUtil.postResponse(url,params);
// System.out.println("第一次请求："+jsonObject);
Boolean success = (Boolean) jsonObject.get("success");
JSONObject data = (JSONObject) jsonObject.get("data");
Boolean isLastPage =(Boolean) data.get("isLastPage");//是否为最后一页
Integer pages =(Integer) data.get("pages");//一共多少页 按每页取多少条进行计算的(共可以获取多少次)
Integer total = (Integer)data.get("total");// 总数据
Integer pageNum = (Integer) data.get("pageNum");//当前页数
Map<String, Object> response = new HashMap<>();
response.put("pages",pages);
response.put("isLastPage",isLastPage);
response.put("total",total);
response.put("data",data);
response.put("pageNum",pageNum);
return response;
}
}
controller
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import com.sun.org.apache.xpath.internal.operations.Bool;
import com.zc.zcdj.domain.LhkjHzhnData;
import com.zc.zcdj.domain.ResponseEntity;
import com.zc.zcdj.mapper.LhkjHzhnDataMapper;
import com.zc.zcdj.service.ILhkjHzhnDataService;
import com.zc.zcdj.utils.HttpClientUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcOperations;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collector;
import java.util.stream.Collectors;
/**
* <p>
* 前端控制器
* </p>
*
* @author guoshanshan
* @since 2023-03-21
*/
@Component
public class LhkjHzhnDataController {
@Autowired
private ILhkjHzhnDataService lhkjHzhnDataService;
@Autowired
private LhkjHzhnDataMapper lhkjHzhnDataMapper;
@Autowired
private JdbcOperations jdbcTemplate;
private static final Logger log = LoggerFactory.getLogger("获取珍诚全量数据");
/**
* 获取珍诚全量数据
*/
// @Scheduled(cron = "0 14 13 ? * *")
// public void getAll(){
// System.out.println("111111111111111111111111111111");
// lhkjHzhnDataService.getProductList();
// }
@Scheduled(cron = "0 49 19 ? * *")
public void getProductList() {
Map<String, String> AllTybm = lhkjHzhnDataMapper.getTybm().stream().filter(s -> s.get统一商品编码() != null).filter(s -> s.get规则() != null).collect(Collectors.toMap(s -> s.get规则(), s -> s.get统一商品编码()));
log.info("第一次请求珍诚接口...");
// 请求第一次获取数据总条数 以及分页后循环次数
Map<String, Object> response = HttpClientUtil.getOneRequest();
Integer pages = (Integer) response.get("pages");//
Integer total = (Integer) response.get("total");
Integer pageNum = (Integer) response.get("pageNum");//当前页数
// Boolean isLastPage = (Boolean) response.get("isLastPage");
// JSONObject data = (JSONObject) response.get("data");
log.info("获取珍诚商品列表全量数据共有" + total + "条,共有" + pages + "页数据");
log.info("珍诚全量开始执行...");
for (int i = 1; i <= pages; i++) {
String url = "http://gateway.zc511.com/getway/v2/product_list_get.shtml";
JSONObject params = new JSONObject();
params.put("timestamp", "1650865510301");
params.put("appKey", "ZBKJ");
params.put("secret", "123");
params.put("sign", "1186D2A92FC3AB4E5671EBF58B9896A6");
params.put("buyerCode", "3330020298-1");
params.put("pageNum", pageNum);
params.put("pageSize", "2000");
JSONObject jsonObject = HttpClientUtil.postResponse(url, params);
log.info("开始获取第" + i + "页数据");
JSONObject data = (JSONObject) jsonObject.get("data");
Boolean isLastPage = (Boolean) data.get("isLastPage");//是否为最后一页
// 获取list中的商品数据 JSONArray
JSONArray list = data.getJSONArray("list");
for (int j = 0; j < list.size(); j++) {
LhkjHzhnData hzhnData = new LhkjHzhnData();
String packingUnit = list.getJSONObject(j).getString("packingUnit");//包装单位
Double salePrice = list.getJSONObject(j).getDouble("salePrice");//销售价
String factory = list.getJSONObject(j).getString("factory");//生产企业
Integer inventoryQuantity = list.getJSONObject(j).getInteger("inventoryQuantity");//库存
Date validDateStr = list.getJSONObject(j).getDate("validDateStr");//有效期
String authorizeNumber = list.getJSONObject(j).getString("authorizeNumber");//国药准字
String barCode = list.getJSONObject(j).getString("barCode");//商品条码
String parseProductName = list.getJSONObject(j).getString("parseProductName");//商品名称
String packingAmount = list.getJSONObject(j).getString("packingAmount");//大包装
String parseProductSpec = list.getJSONObject(j).getString("parseProductSpec");//规格
String minPackingNumber = list.getJSONObject(j).getString("minPackingNumber");//最小购买包装
if (authorizeNumber != null && parseProductSpec != null) {
String authorizeNumberNew = authorizeNumber.replaceAll("[^a-zA-Z/0-9]", "");
String parseProductSpecNew = parseProductSpec.replaceAll("[^0-9]", "");
String tj = authorizeNumberNew.toUpperCase() + parseProductSpecNew;
hzhnData.set统一编码("0");
String tybm = (String) AllTybm.get(tj);
if (tybm != null && tybm != "0") {
hzhnData.set统一编码(tybm);
}
}
hzhnData.set药品名称(parseProductName);
hzhnData.set规格(parseProductSpec);
hzhnData.set产地(factory);
hzhnData.set单位(packingUnit);
hzhnData.set大包装(packingAmount);
hzhnData.set批准文号(authorizeNumber);
hzhnData.set库存数量(inventoryQuantity);
hzhnData.set价格(salePrice);
hzhnData.setTxm(barCode);
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
if (validDateStr != null) {
hzhnData.set有效期(sdf.format(validDateStr));
} else {
hzhnData.set有效期(null);
}
hzhnData.set库区("珍诚");
hzhnData.set供应商("珍诚");
hzhnData.set中包装(minPackingNumber);
Date date = new Date();
SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
hzhnData.setStoragedate(sdf1.format(date));
// hzhnData.set备注();
// hzhnData.setHyid();
System.out.println("第" + (j + 1) + "条" + hzhnData);
lhkjHzhnDataMapper.insert(hzhnData);
}
pageNum += 1;
}
log.info("获取珍诚全量数据运行完毕...");
}
}
若是使用频率比较多，推荐使用对象的形式处理
利用阿里的fastjson，请注意前引用
关于Java对json字符串的处理，可以直接获取；但当使用频率较多的时候，就不太方便了。既然是面向对象编程，那就向json的数据转化为对象！
处理思路：
需要根据接收到的json对象构建对象。
将所有需要的数据全部封装为对象！
再利用阿里（fastjson）/google(Gson)的json转对象的方法
直接转为对象，再直接操作对象
假设以下是我们接收到的json，我们需要的是detail中的数据；
则需要构建实体dataItems以及包含dataItems的实体
然后直接进行转换：
示例代码：实体（假设都是String类型）
dataItems
@Data
public class DataIteams {
private String phoneNum;
private String aramDateTime;
private String aramType;
private String lon;
private String lat;
private String devNo;
private String descripton;
private String since;
private String amc;
}
detail的实体
import java.util.List;
@Data
public class Detail {
private String pageCount;
private String totalCount;
private String pageIndex;
private String pageSize;
/**
*这个实体就是DataItems里面的数据体
*/
private List<DataItems> dataItems;
}
当构建了实体以后就可以利用方法转换了！
示例代码：
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import java.util.HashMap;
public class Main {
public static void main(String[] args) {
String str = "{\n" +
" \"code\": \"0\",\n" +
" \"error\": \"\",\n" +
" \"msg\": \"success\",\n" +
" \"detail\": {\n" +
" \"pageCount\": 1,\n" +
" \"totalCount\": 9,\n" +
" \"pageIndex\": 1,\n" +
" \"pageSize\": 1000,\n" +
" \"dataItems\": [\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1616990185000,\n" +
" \"aramType\": 1,\n" +
" \"lon\": 114.224438,\n" +
" \"lat\": 30.55706,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1616990186000,\n" +
" \"aramType\": 1,\n" +
" \"lon\": 114.224457,\n" +
" \"lat\": 30.557187,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1616990190000,\n" +
" \"aramType\": 1,\n" +
" \"lon\": 114.224484,\n" +
" \"lat\": 30.557565,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1616990195000,\n" +
" \"aramType\": 1,\n" +
" \"lon\": 114.224434,\n" +
" \"lat\": 30.557971,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1616990196000,\n" +
" \"aramType\": 1,\n" +
" \"lon\": 114.224388,\n" +
" \"lat\": 30.558073,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1616990200000,\n" +
" \"aramType\": 1,\n" +
" \"lon\": 114.224297,\n" +
" \"lat\": 30.558436,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1614736039000,\n" +
" \"aramType\": 27,\n" +
" \"lon\": 114.204813,\n" +
" \"lat\": 30.553443,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1615342530000,\n" +
" \"aramType\": 27,\n" +
" \"lon\": 114.216378,\n" +
" \"lat\": 30.561051,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" },\n" +
" {\n" +
" \"phoneNum\": \"027044039989\",\n" +
" \"aramDateTime\": 1616990178000,\n" +
" \"aramType\": 27,\n" +
" \"lon\": 114.222609,\n" +
" \"lat\": 30.554516,\n" +
" \"devNo\": \"\",\n" +
" \"descripton\": \"\",\n" +
" \"since\": \"\",\n" +
" \"amc\": \"\"\n" +
" }\n" +
" ]\n" +
" },\n" +
"}";
//先转换成JSONObject类型
String json = JSON.parseObject(str).getString("detail");
Detail detail = JSONObject.parseObject(json, Detail.class);
System.out.println(detail);
}
}
获得的对象就可以直接使用get和set方法获取数据了
方法：
//Javabean对象转换成String类型的JSON字符串
JSONObject.toJSONString(Javabean对象)
//String类型的JSON字符串转换成Javabean对象
JSONObject.toJavaObject(JSON字符串,Javabean.class)
//Json字符串转换成JSONObject对象
JSONObject.parseObject(JSON字符串)
//JSON字符串转换成Javabean对象
JSONObject.parseObject(JSON字符串,Javabean.class)
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