Android annotations REST

使用前：

public class BookmarksToClipboardActivity extends Activity {
  
  BookmarkAdapter adapter;
 
  ListView bookmarkList;
 
  EditText search;
 
  BookmarkApplication application;
 
  Animation fadeIn;
 
  ClipboardManager clipboardManager;
 
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
 
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(FLAG_FULLSCREEN, FLAG_FULLSCREEN);
 
    setContentView(R.layout.bookmarks);
 
    bookmarkList = (ListView) findViewById(R.id.bookmarkList);
    search = (EditText) findViewById(R.id.search);
    application = (BookmarkApplication) getApplication();
    fadeIn = AnimationUtils.loadAnimation(this, anim.fade_in);
    clipboardManager = (ClipboardManager) getSystemService(CLIPBOARD_SERVICE);
 
    View updateBookmarksButton1 = findViewById(R.id.updateBookmarksButton1);
    updateBookmarksButton1.setOnClickListener(new OnClickListener() {
 
      @Override
      public void onClick(View v) {
        updateBookmarksClicked();
      }
    });
 
    View updateBookmarksButton2 = findViewById(R.id.updateBookmarksButton2);
    updateBookmarksButton2.setOnClickListener(new OnClickListener() {
 
      @Override
      public void onClick(View v) {
        updateBookmarksClicked();
      }
    });
 
    bookmarkList.setOnItemClickListener(new OnItemClickListener() {
 
      @Override
      public void onItemClick(AdapterView<?> p, View v, int pos, long id) {
        Bookmark selectedBookmark = (Bookmark) p.getAdapter().getItem(pos);
        bookmarkListItemClicked(selectedBookmark);
      }
    });
 
    initBookmarkList();
  }
 
  void initBookmarkList() {
    adapter = new BookmarkAdapter(this);
    bookmarkList.setAdapter(adapter);
  }
 
  void updateBookmarksClicked() {
    UpdateBookmarksTask task = new UpdateBookmarksTask();
 
    task.execute(search.getText().toString(), application.getUserId());
  }
  
  private static final String BOOKMARK_URL = //
  "http://www.bookmarks.com/bookmarks/{userId}?search={search}";
  
  
  class UpdateBookmarksTask extends AsyncTask<String, Void, Bookmarks> {
 
    @Override
    protected Bookmarks doInBackground(String... params) {
      String searchString = params[0];
      String userId = params[1];
 
      RestTemplate client = new RestTemplate();
      HashMap<String, Object> args = new HashMap<String, Object>();
      args.put("search", searchString);
      args.put("userId", userId);
      HttpHeaders httpHeaders = new HttpHeaders();
      HttpEntity<Bookmarks> request = new HttpEntity<Bookmarks>(httpHeaders);
      ResponseEntity<Bookmarks> response = client.exchange( //
          BOOKMARK_URL, HttpMethod.GET, request, Bookmarks.class, args);
      Bookmarks bookmarks = response.getBody();
 
      return bookmarks;
    }
 
    @Override
    protected void onPostExecute(Bookmarks result) {
      adapter.updateBookmarks(result);
      bookmarkList.startAnimation(fadeIn);
    }
    
  }
 
  void bookmarkListItemClicked(Bookmark selectedBookmark) {
    clipboardManager.setText(selectedBookmark.getUrl());
  }
 
}

使用后：

@NoTitle
@Fullscreen
@EActivity(R.layout.bookmarks)
public class BookmarksToClipboardActivity extends Activity {
  
  BookmarkAdapter adapter;
  
  @ViewById
  ListView bookmarkList;
 
  @ViewById
  EditText search;
  
  @App
  BookmarkApplication application;
  
  @RestService
  BookmarkClient restClient;
 
  @AnimationRes
  Animation fadeIn;
  
  @SystemService
  ClipboardManager clipboardManager;
 
  @AfterViews
  void initBookmarkList() {
    adapter = new BookmarkAdapter(this);
    bookmarkList.setAdapter(adapter);
  }
  
  @Click({R.id.updateBookmarksButton1, R.id.updateBookmarksButton2})
  void updateBookmarksClicked() {
    searchAsync(search.getText().toString(), application.getUserId());
  }
  
  @Background
  void searchAsync(String searchString, String userId) {
    Bookmarks bookmarks = restClient.getBookmarks(searchString, userId);
    updateBookmarks(bookmarks);
  }
 
  @UiThread
  void updateBookmarks(Bookmarks bookmarks) {
    adapter.updateBookmarks(bookmarks);
    bookmarkList.startAnimation(fadeIn);
  }
  
  @ItemClick
  void bookmarkListItemClicked(Bookmark selectedBookmark) {
    clipboardManager.setText(selectedBookmark.getUrl());
  }
 
}

@Rest("http://www.bookmarks.com")
public interface BookmarkClient {
  
  @Get("/bookmarks/{userId}?search={search}")
  Bookmarks getBookmarks(String search, String userId);
 
}

且利用androidannotations的Rest注解替换手工建立Spring Android RestTemplate对象，不仅可以减少很多代码，同时使工程结构更简洁、严谨，利于复用。

自己构造RestTemplate的原生写法：

HttpHeaders requestHeaders = new HttpHeaders();  
List<MediaType> acceptableMediaTypes = new ArrayList<MediaType>();  
acceptableMediaTypes.add(MediaType.APPLICATION_JSON);  
requestHeaders.setAccept(acceptableMediaTypes);  
                  
HttpEntity<?> requestEntity = new HttpEntity<Object>(requestHeaders);  
                  
RestTemplate restTemplate = new RestTemplate();  
restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());  
                  
ResponseEntity<User[]> responseEntity = restTemplate.exchange(url, HttpMethod.GET, requestEntity, User[].class);  

利用androidannotations的Rest注解替换后的代码：

//初始化
@RestService  
RestApiService restApiService;
ResponseEntity<User[]> responseEntity = restApiService.getByStatus(); 

@Rest(rootUrl = "http://10.0.2.2:8080/together/api", converters = { MappingJackson2HttpMessageConverter.class })  
public interface RestApiService {  
      
    @Get("/user/getByStatus.do?status=1")  
    ResponseEntity<User[]> getUsersByStatus();  
  
}  

wiki api :

https://github.com/excilys/androidannotations/wiki/Rest-API