1:異常信息全部轉(zhuǎn)換字符串

private static String exception(Throwable t) throws IOException {

       if (t == null)

           return null;

       ByteArrayOutputStream baos = new ByteArrayOutputStream();

       try {

           t.printStackTrace(new PrintStream(baos));

       } finally {

           baos.close();

       }

       return baos.toString();

    }