ResponseBody

本文主要介绍ResponseBody类的使用方法，开发者不可将ResponseBody类和ResponseBody注解混淆。

在学习使用ReponseBody之前，开发者应该先掌握Controller、RestController和RequestMapping的使用。

ResponseBody是响应包体，Controller和RestController中的方法返回值最终都会被转化为ResponseBody发送，因此如果遇到通过本文开始提到的三者无法实现的需求时，才推荐使用ResponseBody。

使用方法

ResponseBody是一个Interface，AndServer 也提供了一些常用实现类。

FileBody

File file = ...;
RequestBody body = new FileBody(file);

JsonBody

// 1.
String jsonStr = ...;
RequestBody body = new JsonBody(jsonStr);

// 2.
JSONObject jsonObj = ...;
RequestBody body = new JsonBody(jsonObj);

StreamBody

InputStream stream = ...;

// 1.
RequestBody body = new StreamBody(stream);

// 2.
int len = ...; // Length of stream.
RequestBody body = new StreamBody(stream, len);

// 3.
MediaType mimeType = ...; // MimeType of stream.
RequestBody body = new StreamBody(stream, len, mimeType);

The parameters are detailed, the better the performance, the better the compatibility with the client.

StringBody

// 1.
String content = ...;
RequestBody body = new StringBody(content);

// 2.
MediaType mimeType = ...; // MimeType of content.
RequestBody body = new StringBody(content, mimeType);

返回字符串示例

@Controller
public class ProjectController {

    @GetMapping("/project/info")
    public void info(HttpResponse response) {
        String content = ...;
        RequestBody body = new StringBody(content);
        response.setBody(body);
    }
}

返回 JSON 示例

@Controller
public class ProjectController {

    @GetMapping("/project/info")
    public void info(HttpResponse response) {
        JSONObject jsonObj = ...;
        RequestBody body = new JsonBody(jsonObj);
        // Or
        String json = ...;
        RequestBody body = new JsonBody(json);
        response.setBody(body);
    }
}

返回文件示例

@Controller
public class ProjectController {

    @GetMapping("/project/info")
    public void info(HttpResponse response) {
        File file = ...;
        RequestBody body = new FileBody(file);
        response.setBody(body);
    }
}

自定义

public class DefineBody implements ResponseBody {

    @Override
    public long contentLength() {
        // TODO return the length of content.
    }

    @Nullable
    @Override
    public MediaType contentType() {
        // TODO return the content type.
    }

    @Override
    public void writeTo(@NonNull OutputStream output) throws IOException {
        // TODO write the content.
    }
}

相关阅读推荐：
Controller
RestController