使用RestTemplate發送post請求

最近使用RestTemplate發送post請求，遇到了很多問題，如轉換httpMessage失敗、中文亂碼等，調了好久才找到下面較為簡便的方法：

RestTemplate restTemplate = new RestTemplate();
        HttpHeaders headers = new HttpHeaders();
        MediaType type = MediaType.parseMediaType("application/json; charset=UTF-8");
        headers.setContentType(type);
        headers.add("Accept", MediaType.APPLICATION_JSON.toString());
        
        JSONObject jsonObj = JSONObject.fromObject(params);
        
        HttpEntity<String> formEntity = new HttpEntity<String>(jsonObj.toString(), headers);

        String result = restTemplate.postForObject(url, formEntity, String.class);

如果直接使用在postForObject中把對象傳入很容易出現no suitable HttpMessageConverter found for request type的錯誤，建議直接先轉成字符串，見jsonObj.otString()，
網上有人說設置RestTemplate的HttpMessageConverter，試了一下要引入各種包。
另外要注意中文編碼問題，網上有人說StringHttpMessageConverter默認使用ISO-8859-1，要指定為UTF-8編碼，自己嘗試沒有成功，最后通過指定contentType的方式解決了。

 

http://liuxing.info/2015/05/21/RestTemplate實踐/

http://www.cnblogs.com/zemliu/archive/2013/07/28/3220517.html

 

 /**
        *
        * This is going to setup the REST server configuration in the applicationContext
        * you can see that I am using the new Spring's Java Configuration style and not some OLD XML file
        *
        */
       ApplicationContext context = new AnnotationConfigApplicationContext(RESTConfiguration.class);

       /**
        *
        * We now get a RESTServer bean from the ApplicationContext which has all the data we need to
        * log into the REST service with.
        *
        */
       RESTServer mRESTServer = context.getBean(RESTServer.class);

       /**
        *
        * Setting up BASIC Authentication access
        *
        */

        HttpClient client = new HttpClient();
       UsernamePasswordCredentials credentials =
               new UsernamePasswordCredentials(mRESTServer.getUser(), mRESTServer.getPassword());

       client.getState().setCredentials(
               new AuthScope(mRESTServer.getHost(), 8080, AuthScope.ANY_REALM),
               credentials);

       CommonsClientHttpRequestFactory commons = new CommonsClientHttpRequestFactory(client);



       /**
        *
        * Setting up data to be sent to REST service
        *
        */
       Map<String, String> vars = new HashMap<String, String>();
       vars.put("id", "INID");

       /**
        *
        * Doing the REST call and then displaying the data/user object
        *
        */
       try
       {

           /*

               This is code to post and return a user object

            */

           RestTemplate rt = new RestTemplate(commons); // Added the CommonsClientHttpRequestFactory

           rt.getMessageConverters().add(new MappingJacksonHttpMessageConverter());
           rt.getMessageConverters().add(new StringHttpMessageConverter());

           String uri = new String("http://" + mRESTServer.getHost() + ":8080/springmvc-resttemplate-auth-test/api/{id}");

           User u = new User();
           u.setName("Johnathan M Smith");
           u.setUser("JMS");


           User returns = rt.postForObject(uri, u, User.class, vars);

           LOGGER.debug("User:  " + u.toString());

https://github.com/JohnathanMarkSmith/springmvc-resttemplate-auth-test

        /**
         *
         * This is going to setup the REST server configuration in the applicationContext
         * you can see that I am using the new Spring's Java Configuration style and not some OLD XML file
         *
         */
        ApplicationContext context = new AnnotationConfigApplicationContext(RESTConfiguration.class);

        /**
         *
         * We now get a RESTServer bean from the ApplicationContext which has all the data we need to
         * log into the REST service with.
         *
         */
        RESTServer mRESTServer = context.getBean(RESTServer.class);



        /**
         *
         * Setting up data to be sent to REST service
         *
         */
        Map<String, String> vars = new HashMap<String, String>();
        vars.put("id", "JS01");




        /**
         *
         * Doing the REST call and then displaying the data/user object
         *
         */


        try
        {

            /*

                This is code to post and return a user object

             */

            RestTemplate rt = new RestTemplate();
            rt.getMessageConverters().add(new MappingJacksonHttpMessageConverter());
            rt.getMessageConverters().add(new StringHttpMessageConverter());

            String uri = new String("http://" + mRESTServer.getHost() + ":8080/springmvc-resttemplate-test/api/{id}");

            User u = new User();
            u.setName("Johnathan M Smith");
            u.setUser("JS01");


            User returns = rt.postForObject(uri, u, User.class, vars);
            LOGGER.debug("User:  " + u.toString());

https://github.com/JohnathanMarkSmith/springmvc-resttemplate-test