dropbox preview api test

testPreview.java

@Test
    public final void testPreview() throws UnsupportedEncodingException {
        DropboxContentReq req = new DropboxContentReq(DropboxAPI.PREVIEW);
        req.setEnd_point(DropboxAPIConfig.content_endpoint);
        req.setHttp_method(HttpMethod.POST);
        DropboxPathReq path_req = new DropboxPathReq("");
        String path = "/blackdog/中文prd.docx";
        //convert Chinese to Unicode /blackdog/\\u4E2D\\u6587prd.docx
        path = StringEscapeUtils.escapeJava(path);
        path_req.setPath(path);
        String header_json = JsonUtils.writeValue(path_req);
        LoggerUtils.logInfo(this.getClass(), header_json);
        req.getHeaders().add("Dropbox-API-Arg",header_json);
        String json = dropbox_api_service.callDropbox(req);
        LoggerUtils.logInfo(this.getClass(), json);
    }
    
    
    
    //resttemplate with httpclient to send http request to dropbox api
    package com.future.auction.agent.service;

import org.springframework.boot.web.client.RestTemplateBuilder;
import org.springframework.http.HttpEntity;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import com.future.auction.agent.model.dropbox.DropboxContentReq;
import com.future.auction.agent.model.dropbox.DropboxReq;
import com.future.auction.utils.LoggerUtils;

@Service
public class DropboxAPIService {

    private RestTemplate restTemplate;

    public DropboxAPIService(RestTemplateBuilder restTemplateBuilder) {
        this.restTemplate = restTemplateBuilder.build();
    }


    public String callDropbox(DropboxReq req) {
        
        HttpEntity<DropboxReq> requestEntity = new HttpEntity<DropboxReq>(req, req.getHeaders());

        if(req instanceof DropboxContentReq){
            requestEntity = new HttpEntity<DropboxReq>(req.getHeaders());
        }
        ResponseEntity<String> resp_entity;
        try {
            resp_entity = restTemplate.exchange(req.buildReqURL(), req.getHttp_method(),
                    requestEntity, String.class);
            LoggerUtils.logInfo(this.getClass(), resp_entity);
            return resp_entity.getBody();
        } catch (Exception e) {
            LoggerUtils.logException(this.getClass(), "dropbox api service exception " + req.buildReqURL(),e);
        }
        return "";
    }
}