// 创建请求
MediaType MEDIA_TYPE = MediaType.parse("application/json; charset=utf-8");
Request request = new Request.Builder()
                        .post(RequestBody.create(MEDIA_TYPE, json))
                        .url(url)
                        .build();
// 创建响应
Response response = client.newCall(request).execute();  // sync
Response response = client.newCall(request).enqueue(new Callback() { // async
                   @Override
                    public void onFailure(Call call, IOException e) {
                    }
                    @Override
                    public void onResponse(Call call, Response response) throws IOException {
                    }
                });
// 获取结果
if (response.isSuccessful()) {
     response.body().string();
}
// 超时设置
// 提交JSON数据示例
    public static void postJsonExamAsync() {
        String url = "http:localhost:8080/login/commitUserInfo";
        String postJson = "{}";
        RequestBody body = RequestBody.create(MEDIA_TYPE, postJson);
        Request request = new Request.Builder()
                .url(url)
                .post(body)
                .build();
        client.newCall(request).enqueue(new Callback() {
            @Override
            public void onFailure(Call call, IOException e) {
                e.printStackTrace();
            }
            @Override
            public void onResponse(Call call, Response response) throws IOException {
                if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);
                Headers responseHeaders = response.headers();
                for (int i = 0; i < responseHeaders.size(); i++) {
                    System.out.println(responseHeaders.name(i) + ": " + responseHeaders.value(i));
                }
                System.out.println(response.body().string());
            }
        });
    }