添加菜单API的支持

src/main/java/chanjarster/weixin/api/WxServiceImpl.java

@@ -0,0 +1,173 @@
+package chanjarster.weixin.api;
+
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.methods.CloseableHttpResponse;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.entity.StringEntity;
+import org.apache.http.impl.client.BasicResponseHandler;
+import org.apache.http.impl.client.CloseableHttpClient;
+import org.apache.http.impl.client.HttpClients;
+
+import chanjarster.weixin.bean.WxAccessToken;
+import chanjarster.weixin.bean.WxCustomMessage;
+import chanjarster.weixin.bean.WxError;
+import chanjarster.weixin.bean.WxMenu;
+import chanjarster.weixin.exception.WxErrorException;
+
+public class WxServiceImpl implements WxService {
+
+  /**
+   * 全局的是否正在刷新Access Token的flag
+   * true: 正在刷新
+   * false: 没有刷新
+   */
+  protected static final AtomicBoolean GLOBAL_ACCESS_TOKEN_REFRESH_FLAG = new AtomicBoolean(false);
+  
+  protected static final CloseableHttpClient httpclient = HttpClients.createDefault();
+  
+  protected static final Charset UTF8 = Charset.forName("UTF-8");
+  
+  protected WxConfigProvider wxConfigProvider;
+  
+  public void refreshAccessToken() throws WxErrorException {
+    if (!GLOBAL_ACCESS_TOKEN_REFRESH_FLAG.getAndSet(true)) {
+      try {
+        String url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential"
+            + "&appid=" + wxConfigProvider.getAppId() 
+            + "&secret=" + wxConfigProvider.getSecret()
+            ;
+        try {
+          HttpGet httpGet = new HttpGet(url);
+          CloseableHttpResponse response = httpclient.execute(httpGet);
+          String resultContent = new BasicResponseHandler().handleResponse(response);
+          WxAccessToken accessToken = WxAccessToken.fromJson(resultContent);
+          wxConfigProvider.updateAccessToken(accessToken.getAccess_token(), accessToken.getExpires_in());
+        } catch (ClientProtocolException e) {
+          throw new RuntimeException(e);
+        } catch (IOException e) {
+          throw new RuntimeException(e);
+        }
+      } finally {
+        GLOBAL_ACCESS_TOKEN_REFRESH_FLAG.set(false);
+      }
+    } else {
+      // 每隔100ms检查一下是否刷新完毕了
+      while (GLOBAL_ACCESS_TOKEN_REFRESH_FLAG.get()) {
+        try {
+          Thread.sleep(100);
+        } catch (InterruptedException e) {
+        }
+      }
+      // 刷新完毕了，就没他什么事儿了
+    }
+  }
+  
+  /**
+   * 发送客服消息
+   * 详情请见: http://mp.weixin.qq.com/wiki/index.php?title=发送客服消息
+   * @param message
+   * @throws WxErrorException
+   */
+  public String sendCustomMessage(WxCustomMessage message) throws WxErrorException {
+    String url = "https://api.weixin.qq.com/cgi-bin/message/custom/send";
+    return post(url, message.toJson());
+  }
+  
+  protected String post(String uri, String data) throws WxErrorException {
+    return execute("POST", uri, data);
+  }
+  
+  protected String get(String uri, String data) throws WxErrorException {
+    return execute("GET", uri, data);
+  }
+
+  /**
+   * 向微信端发送请求，在这里执行的策略是当发生access_token过期时才去刷新，然后重新执行请求，而不是全局定时请求
+   * @param request
+   * @return 微信服务端返回的结果
+   * @throws WxErrorException 
+   */
+  protected String execute(String method, String uri, String data) throws WxErrorException {
+    if (StringUtils.isBlank(wxConfigProvider.getAccessToken())) {
+      refreshAccessToken();
+    }
+    String accessToken = wxConfigProvider.getAccessToken();
+    
+    String uriWithAccessToken = uri;
+    uriWithAccessToken += uri.indexOf('?') == -1 ? "?access_token=" + accessToken : "&access_token=" + accessToken;
+    
+    try {
+      String resultContent = null;
+      if ("POST".equals(method)) {
+        HttpPost httpPost = new HttpPost(uriWithAccessToken);
+        StringEntity entity = new StringEntity(data, UTF8);
+        httpPost.setEntity(entity);
+        CloseableHttpResponse response = httpclient.execute(httpPost);
+        resultContent = new BasicResponseHandler().handleResponse(response);
+      } else if ("GET".equals(method)) {
+        HttpGet httpGet = new HttpGet(uriWithAccessToken);
+        CloseableHttpResponse response = httpclient.execute(httpGet);
+        resultContent = new BasicResponseHandler().handleResponse(response);
+      }
+      
+      WxError error = WxError.fromJson(resultContent);
+      /*
+       * 关于微信返回错误码 详情请看 http://mp.weixin.qq.com/wiki/index.php?title=全局返回码说明
+       * 40001 微信图片不对
+       * 42001 access_token超时
+       */
+      if (error.getErrcode() == 42001 || error.getErrcode() == 40001) {
+        refreshAccessToken();
+        return execute(method, uri, data);
+      }
+      if (error.getErrcode() != 0) {
+        throw new WxErrorException(error);
+      }
+      return resultContent;
+    } catch (ClientProtocolException e) {
+      throw new RuntimeException(e);
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+  }
+  
+  /**
+   * 
+   * @param menu
+   * @throws WxErrorException
+   */
+  public String createMenu(WxMenu menu) throws WxErrorException {
+    // TODO
+    return null;
+  }
+  
+  /**
+   * 
+   * @throws WxErrorException
+   */
+  public String deleteMenu() throws WxErrorException {
+ // TODO
+    return null;
+  }
+
+  /**
+   * 
+   * @return
+   * @throws WxErrorException
+   */
+  public WxMenu getMenu() throws WxErrorException {
+    // TODO
+    return null;
+  }
+  
+  public void setWxConfigProvider(WxConfigProvider wxConfigProvider) {
+    this.wxConfigProvider = wxConfigProvider;
+  }
+
+}