我查询少量数据时没问题，当查询上千条纪录时，出现一下错误

http://www.iteye.com/post/6107
我查询少量数据时没问题，当查询上千条纪录时，出现一下错误：
net.sf.hibernate.impl.IteratorImpl next 严重: could not get next result
  java.lang.OutOfMemoryError rethrown as net.sf.hibernate.InstantiationException: Could not instantiate entity with CGLIB:
wanzitest1.Wanzi
这是什么错误啊！
加大jvm的内存或者

Iterator cats = sess.iterate("from eg.Cat as cat");; //a huge result set  
while ( cats.hasNext(); ); {  
    Cat cat = (Cat); iter.next();;  
    doSomethingWithACat(cat);;  
    sess.evict(cat);;  
}