oracle中resultset错误

在oracle中用jdbc来连接数据库，为什么Resultset里面嵌套ResultSet,到循环的第二次就报空指针，哪位知道是怎么回事吗？
代码：Java code:
while(prors.next()){
System.out.println(prors.getRow());
Date startime = prors.getTime("starttime");
String st = sf.format(startime);
String ft = sf.format(prors.getTime("finishtime"));
int rt = (int) (sf.parse(ft).getTime()-sf.parse(st).getTime())/1000;
int ssid = prors.getInt("seresscriptid"); //找到系列的id
String ssql = "select * from seriescript where id ="+ssid;
ResultSet srs = stmt.executeQuery(ssql);
srs.absolute(1);
System.out.println(srs.getString("name"));//获取脚本系列的名字
srs.beforeFirst();
}



报错如下：
Java code:
Exception in thread "main" java.lang.NullPointerException
at oracle.jdbc.driver.ScrollableResultSet.cacheRowAt(ScrollableResultSet.java:1588)
at oracle.jdbc.driver.ScrollableResultSet.isValidRow(ScrollableResultSet.java:1571)
at oracle.jdbc.driver.ScrollableResultSet.next(ScrollableResultSet.java:301)
at test.main(test.java:49)