修正异常处理的问题

git-svn-id: http://code.alibabatech.com/svn/druid/trunk@20 b9813039-fb51-4c41-a8b9-e21c2acb5095

src/main/java/com/alibaba/druid/pool/DruidDataAbstractSource.java

@@ -491,9 +491,15 @@ public abstract class DruidDataAbstractSource implements DataSource, DataSourceP
     }
 
     @Override
-    public PrintWriter getLogWriter() throws SQLException {
+    public PrintWriter getLogWriter() {
         return logWriter;
     }
+    
+    protected void printStackTrace(Throwable e) {
+        if (logWriter != null) {
+            e.printStackTrace(logWriter);
+        }
+    }
 
     @Override
     public void setLogWriter(PrintWriter out) throws SQLException {