Angular4 JSONP + JAVA代码

一、在app.module.ts模块中，注入JsonpModule模块

import {JsonpModule} from "@angular/http";

@NgModule({
    imports: [
        JsonpModule    //注入JSonpModule模块
    ]
})

二、创建服务httpService，并注入jsonp和map（分装好的服务 可以直接调用）

import {Injectable} from '@angular/core';
import {Jsonp, URLSearchParams} from "@angular/http";

@Injectable()
export class HttpService {

    private jsonpTimes = 0;   // 用于记录jsonp请求的次数

    constructor(private jsonp: Jsonp) {

    }

    jsonpGet(apiURL, req){
        let params = new URLSearchParams();
        //设置参数
        for (let key in req) {
            params.set(key, req[key]);
        }
        params.set('format', 'json');
        params.set("callback", `__ng_jsonp__.__req${this.jsonpTimes}.finished`);
        this.jsonpTimes++;

        let request = this.jsonp.get(apiURL, { search: params })
            .map((res) => {
                let response = res.json();
                return response;
            });
        return request;
    }

}

三、业务组件调用httpService

let newUrl = localServer + "/search"; //查询网址 

let req = { id: 123, name: "abc" }; //查询参数

this.httpService.jsonpGet(newUrl, req).subscribe(data => {
            let result = data.data;
        });

后端JAVA代码

@RequestMapping(value = "mergeJson")
     public void exchangeJson(HttpServletRequest request,HttpServletResponse response)  throws Exception {
              String businessnum = request.getParameter("businessnum");
              String paths = request.getParameter("paths");
              List<String>  pathList =  Arrays.asList( paths.split(","));  

              List<String> resultPath = mergeService.merge(businessnum, pathList);
              String return_JSONP = String.join(",", resultPath);
              String jsonCallback = request.getParameter("callback"); //jsonpCallback 客户端请求参数
              Map<String,Object> map = new HashMap<>();
              map.put("data",return_JSONP);
              JSONObject resultJSON = new JSONObject(map);//根据需要拼装json  

              PrintWriter pw = response.getWriter();
              pw.write(jsonCallback+"("+resultJSON+")");
              pw.close();
              pw = null;
        }  

参考资料：https://www.cnblogs.com/minigrasshopper/p/7692368.html