数据库Clob类型转String类型

Clob c=(Clob)sqlRowSet.getObject("SERVICE_XQUERY");
String str="";
if(c!=null){
	Reader is = null;				
	try {
	is = c.getCharacterStream();
		BufferedReader br = new BufferedReader(is);  
		str=br.readLine();  
	} catch (Exception e) {
		e.printStackTrace();
	}
}