java：接口请求_java 请求接口-优快云博客

本文链接：https://blog.youkuaiyun.com/a232884c/article/details/123261353

本文介绍了如何在SpringBoot中创建GET、POST等HTTP请求接口，并展示了如何使用Java工具类进行接口请求，包括无参、有参的POST请求和GET请求。通过示例代码展示了快速构建请求参数和处理响应的方法。

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java：接口请求

1 前言

构建java请求接口的工具类前，先使用SpringBoot增加get、post请求的有参、无参接口。如下：

package com.xiaoxu.controller;

import com.google.common.collect.ImmutableMap;
import com.xiaoxu.domain.Fruit;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.PropertySource;
import org.springframework.web.bind.annotation.*;

import javax.servlet.http.HttpServletRequest;
import java.util.*;

/**
 * @author xiaoxu
 * @date 2022-01-10
 * Ymybatis:com.xiaoxu.controller.FruitController
 */
@PropertySource(value = {"classpath:jdbc.properties","classpath:application.yml","classpath:ts.properties"},encoding = "utf-8")
@RestController
@Slf4j
public class FruitController {
//    @Autowired
//    @Qualifier(value = "myfruit")
//    Fruit f;

    @Autowired
//    @Qualifier(value = "myfruit")
    @Qualifier(value = "lizhi_fruit")
    Fruit f;

//    @Value("#{new BigDecimal(\"12.0\").add(new BigDecimal(\"15.0\"))}")
    @Value("#{'Xiaoxu'}")
    String a;

    @Value("${name}")
    String o;

    @GetMapping("/fruit/{id}/shop/{address}")
    public Map<String,Object> getFruitByAddress(@PathVariable("id") Integer myId,
                                                @PathVariable("address") String ads,
                                                @PathVariable Map<String,String> map,
                                                @RequestHeader("User-Agent") String header,
                                                @RequestHeader Map<String,String> headers)
                                                {
        return ImmutableMap.<String,Object>builder().put("number",myId)
                .put("MyAddress",ads)
                .put("KV",map)
                .put("singleUserAgent",header)
                .put("allHeaders",headers)
//                .put("body",body)
                .build();
    }

    @RequestMapping(path = "/fruit",method = RequestMethod.GET)
    public Map<String,Object> fruit(){
        return new HashMap<String,Object>(){{
            put("Get",f);
            put("你好","wohao");
            put("我很好","nine");
        }};
    }

    @RequestMapping(value = "/myfruit",method = RequestMethod.POST)
    public Map<String,Object> myfruit(){
        return ImmutableMap.<String,Object>builder()
                .put("value1",a)
                .put("value2",o)
                .build();
    }

    @RequestMapping(value = "/newFruit",method = RequestMethod.POST)
    public Map<String,Object> newFr(@RequestParam Map<String,Object> payload){
        return ImmutableMap.<String,Object>builder()
                .put("payload",payload)
                .build();
    }

    @RequestMapping(value = "/newFruit2",method = {RequestMethod.GET,RequestMethod.POST})
    public Map<String,Object> newFr2(HttpServletRequest request){
        String number = request.getParameter("number");
        String[] members = request.getParameter("members").split(",");
        List<String> m = Arrays.asList(members);
        log.info("我是成员们：{}",m);
        return ImmutableMap.<String,Object>builder()
                .put("拿到参数",number)
                .put("haha",new HashMap<String,String>(){{put("哈哈","嘿嘿");put("嘻嘻","到");}})
                .put("哇喔","11111111")
                .put("拿到成员",m)
                .build();
    }

    @RequestMapping(value = "/fruit222",method = RequestMethod.POST)
    public Map<String,Object> fruit1(){
        return new HashMap<String,Object>(){{
            put("Post",f);
        }};
    }

    @RequestMapping(value = "/fruit",method = RequestMethod.DELETE)
    public Map<String,Object> fruit2(){
        return new HashMap<String,Object>(){{
            put("Delete",f);
        }};
    }


    @RequestMapping(path = "/fruit",method=RequestMethod.PUT)
    public Map<String,Object> fruit3(){
        return ImmutableMap.<String,Object>builder().put("Put",f).build();
    }
}

2 构建java接口请求工具类

请求方式枚举：

package com.xiaoxu.enums;


public enum RequestMethodEnum {
    // 避免java.net.ProtocolException: Invalid HTTP method: get 以及
    // java.net.ProtocolException: Invalid HTTP method: post异常,应该是GET和POST
    GET("GET","get请求","01"),
    POST("POST","post请求","02");
    private String name;
    private String description;
    private String code;

    RequestMethodEnum(String name,String description,String code){
        this.name = name;
        this.description = description;
        this.code = code;
    }
    //根据code获取请求方式
    public static RequestMethodEnum getMethodByCode(String code){
        for (RequestMethodEnum value : RequestMethodEnum.values()) {
            if(value.getCode().equals(code)){
                return value;
            }
        }
        return null;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getCode() {
        return code;
    }

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

fastjson依赖：

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.79</version>
</dependency>

java接口请求封装的工具类：

package com.xiaoxu.utils;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.xiaoxu.enums.RequestMethodEnum;
import org.springframework.stereotype.Component;


import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.*;

/**
 * @author xiaoxu
 * @date 2022-03-03
 * spring_boot:com.xiaoxu.utils.RequestUtil
 */
@Component
public class RequestUtil {

    public static void main(String[] args) {
        RequestUtil.request();
    }

    public static void request(){

        //1  post 无参
        String path1 = "http://localhost:8088"+"/myfruit";
        //2  get  无参
        String path2 = "http://localhost:8088"+"/fruit";
        //3  post 有参
        String path3 = "http://localhost:8088"+"/newFruit";
        //4  get 有参
        String path4 = "http://localhost:8088"+"/newFruit2";

        //1  post 无参
        System.out.println("*************第1次请求************");
        RequestUtil.printPrettyJsonResult(RequestUtil.buildRequest(RequestMethodEnum.POST.getName(), path1,null,null));

        //2  get  无参
        System.out.println("*************第2次请求************");
        RequestUtil.printPrettyJsonResult(RequestUtil.buildRequest(RequestMethodEnum.GET.getName(), path2,"",null));

        //3  post 有参
        System.out.println("*************第3次请求************");
        String payload = RequestUtil.buildPayloadStr(new HashMap<String,Object>(){{
            put("name","xiaoxu");
            put("age",18);
            put("interests",new ArrayList<String>(){{add("羽毛球");add("sing");}});
        }});
        RequestUtil.printPrettyJsonResult(RequestUtil.buildRequest(RequestMethodEnum.POST.getName(),path3,payload,null));

        //4  get 有参
        System.out.println("*************第4次请求************");
        String param = RequestUtil.buildParamsStr(new HashMap<String,Object>(){{
            put("members",new ArrayList<String>(){{add("小徐");add("小李");}});
            put("number","9527");
            put("name","小黑");
            put("book","打字入门");
        }});
        RequestUtil.printPrettyJsonResult(RequestUtil.buildRequest(RequestMethodEnum.GET.getName(),path4,param,null));
    }


    public static String buildRequest(String method, String urlPath, String data, Map<String,String> headerMap){
        StringBuilder str = new StringBuilder();
        try {
            //处理data,如果data为null，转换成""，否则data.getBytes会抛出空指针异常
            data = Optional.ofNullable(data).orElse("");
            data = data.replace(" ","");
            if("get".equals(method.toLowerCase(Locale.ROOT))){
                //get请求需要拼接路径（无参数，data应该是""，有参数则拼接）
                urlPath+=data;
            }
//            System.out.println("请求的url："+urlPath);
            URL url = new URL(urlPath);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            if(headerMap!=null){
                //设置请求头的属性,比如：Cookie,Token等等
                //System.out.println("key:"+k+";"+"value:"+v);
                headerMap.forEach(connection::setRequestProperty);
            }
            //设置请求方式
            connection.setRequestMethod(method);
            //post不同于get，get只需要将请求参数拼接到url中，而post请求的是正文
            if("post".equals(method.toLowerCase(Locale.ROOT))){
                // post请求不能使用缓存
                connection.setUseCaches(false);
                // post参数不是放在URL字符串里，而是http请求的正文
                // post:http正文内，因此需要设为true
                connection.setDoOutput(true);
                //connection获取输出的流，write写入post请求的参数：格式：key=value&key1=value1
                OutputStream outputStream = connection.getOutputStream();
                //String的getBytes,字符串转字节
                byte[] postBytes = data.getBytes(StandardCharsets.UTF_8);
                outputStream.write(postBytes);
            }
            //获取URLConnection对象对应的输入流
            InputStream in = connection.getInputStream();
            //将接口请求的接口打印出来
            BufferedReader b = new BufferedReader(new InputStreamReader(in));
            String s;
            while((s=b.readLine())!=null){
                str.append(s);
            }
            //关闭流
            in.close();
            //关闭连接
            connection.disconnect();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return str.toString();
    }

    //构建post请求参数，类似：key = value & key1 = value1
    //当post请求是Content-Type：x-www-form-urlencoded（表单提交时使用）
    public static String buildPayloadStr(Map<String,Object> payloadMap){
        StringBuilder s = new StringBuilder();
        for(Map.Entry<String,Object> m:payloadMap.entrySet()){
            if(s.length()==0){
                s.append(m.getKey()).append("=").append(m.getValue());
            }else{
                s.append("&").append(m.getKey()).append("=").append(m.getValue());
            }
        }
        return s.toString();
    }

    //构建post请求2:json字符串格式，当请求头设置了"Content-Type","application/json;charset=UTF-8"时使用
    public static String buildJsonPayloadStr(Map<String,Object> payloadMap){
        return JSON.toJSONString(payloadMap);
    }

    //构建get请求的参数url，类似：?key=value&key1=value1
    public static String buildParamsStr(Map<String,Object> paramsMap){
        paramsMap = Optional.ofNullable(paramsMap).orElse(new HashMap<>());
        StringBuilder s = new StringBuilder();
        StringBuilder temp = new StringBuilder();
        try{
            for(Map.Entry<String,Object> m: paramsMap.entrySet()) {
                if (m.getValue() instanceof List) {
                    Iterator<?> iter =((List<?>) m.getValue()).iterator();
                    StringBuilder rep = new StringBuilder();
                    while(iter.hasNext()){
                        String s1 = String.valueOf(iter.next());
                        if(rep.length()==0){
                            rep.append(URLEncoder.encode(m.getKey(),"utf-8")).append("=").append(URLEncoder.encode(s1,"utf-8"));
                        }else{
                            rep.append(URLEncoder.encode(",","utf-8")).append(URLEncoder.encode(s1,"utf-8"));
                        }
                    }
                    if(temp.length()==0){
                        temp.append(rep);
                    }else{
                        temp.append("&").append(rep);
                    }
                } else if(m.getValue() instanceof String){
                    if(temp.length()==0){
                        temp.append(URLEncoder.encode(m.getKey(),"utf-8")).append("=").append(URLEncoder.encode(String.valueOf(m.getValue()),"utf-8"));
                    }else{
                        temp.append("&").append(URLEncoder.encode(m.getKey(),"utf-8")).append("=").append(URLEncoder.encode(String.valueOf(m.getValue()),"utf-8"));
                    }
                }else if(m.getValue() instanceof Integer){
                    if(temp.length()==0){
                        temp.append(URLEncoder.encode(m.getKey(),"utf-8")).append("=").append(URLEncoder.encode(String.valueOf(m.getValue()),"utf-8"));
                    }else{
                        temp.append("&").append(URLEncoder.encode(m.getKey(),"utf-8")).append("=").append(URLEncoder.encode(String.valueOf(m.getValue()),"utf-8"));
                    }
                }
                else{
                    throw new RuntimeException("存在value非String或者List或非Integer的数据");
                }
            }
        }catch (UnsupportedEncodingException e){
            e.printStackTrace();
        }catch (Exception e){
            throw new RuntimeException("未知异常：" + e.getMessage());
        }
        if (temp.length() != 0) {
            s.append("?").append(temp);
        }
        return s.toString();
    }

    public static void printPrettyJsonResult(String s){
        JSONObject jsonObject = JSON.parseObject(s);
        System.out.println("接口返回结果:");
        System.out.println(JSON.toJSONString(jsonObject, SerializerFeature.PrettyFormat));
    }
}

执行RequestUtil的main方法，结果如下：

*************第1次请求************
请求的url：http://localhost:8088/myfruit
接口返回结果:
{
	"value2":"李红",
	"value1":"Xiaoxu"
}
*************第2次请求************
请求的url：http://localhost:8088/fruit
接口返回结果:
{
	"你好":"wohao",
	"Get":{
		"fname":"菠萝",
		"price":14.6,
		"count":300,
		"dropDate":"2022-01-10T04:00:00.000+00:00"
	},
	"我很好":"nine"
}
*************第3次请求************
请求的url：http://localhost:8088/newFruit
接口返回结果:
{
	"payload":{
		"name":"xiaoxu",
		"interests":"[羽毛球,sing]",
		"age":"18"
	}
}
*************第4次请求************
请求的url：http://localhost:8088/newFruit2?number=9527&members=%E5%B0%8F%E5%BE%90%2C%E5%B0%8F%E6%9D%8E&book=%E6%89%93%E5%AD%97%E5%85%A5%E9%97%A8&name=%E5%B0%8F%E9%BB%91
接口返回结果:
{
	"拿到参数":"9527",
	"haha":{
		"哈哈":"嘿嘿",
		"嘻嘻":"到"
	},
	"哇喔":"11111111",
	"拿到成员":[
		"小徐",
		"小李"
	]
}