增加生成授权链接方法，重定向链接可直接读取配置。

weixin-java-cp/src/main/java/me/chanjar/weixin/cp/api/WxCpService.java

@@ -392,6 +392,16 @@ public interface WxCpService {
    */
   void tagAddUsers(String tagId, List<String> userIds, List<String> partyIds) throws WxErrorException;
 
+  /**
+   *  <pre>
+   * 构造oauth2授权的url连接
+   * </pre>
+   * 
+   * @param state
+   * @return
+   */
+  String oauth2buildAuthorizationUrl(String state);
+  
   /**
    * <pre>
    * 构造oauth2授权的url连接

weixin-java-cp/src/main/java/me/chanjar/weixin/cp/api/WxCpServiceImpl.java

@@ -444,6 +444,14 @@ public class WxCpServiceImpl implements WxCpService {
   }
 
   @Override
+	public String oauth2buildAuthorizationUrl(String state) {
+  	return this.oauth2buildAuthorizationUrl(
+  		this.wxCpConfigStorage.getOauth2redirectUri(),
+  		state
+  	);
+	}
+
+	@Override
   public String oauth2buildAuthorizationUrl(String redirectUri, String state) {
     String url = "https://open.weixin.qq.com/connect/oauth2/authorize?";
     url += "appid=" + wxCpConfigStorage.getCorpId();