Update DefaultDataHandler.java

tdenginewriter/src/main/java/com/alibaba/datax/plugin/writer/tdenginewriter/DefaultDataHandler.java

@@ -47,6 +47,16 @@ public class DefaultDataHandler implements DataHandler {
 
     private Map<String, List<ColumnMeta>> columnMetas;
 
+    
+    static {
+        try {
+            Class.forName("com.taosdata.jdbc.TSDBDriver");
+            Class.forName("com.taosdata.jdbc.rs.RestfulDriver");
+        } catch (ClassNotFoundException e) {
+            e.printStackTrace();
+        }
+    }
+    
     public DefaultDataHandler(Configuration configuration) {
         this.username = configuration.getString(Key.USERNAME, Constants.DEFAULT_USERNAME);
         this.password = configuration.getString(Key.PASSWORD, Constants.DEFAULT_PASSWORD);
@@ -460,4 +470,4 @@ public class DefaultDataHandler implements DataHandler {
                 "cannot find col: " + colName + " in columns: " + columns);
     }
 
-}
+}