一个Hibernate中映射文件里设置引起的错误

昨天在试书里的一个例子，程序运行时提示如下错误：

ERROR [main] ( CGLIBLazyInitializer.java : 130 ) - CGLIB Enhancement failed: hibernate.ch05.section02.SC - [org.hibernate.proxy.CGLIBLazyInitializer] -org.hibernate.proxy.CGLIBLazyInitializer.getProxyFactory(CGLIBLazyInitializer.java:130)

net.sf.cglib.core.CodeGenerationException: java.lang.reflect.InvocationTargetException-->null

at net.sf.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:237)

at net.sf.cglib.proxy.Enhancer.createHelper(Enhancer.java:377)

at net.sf.cglib.proxy.Enhancer.createClass(Enhancer.java:317)

at org.hibernate.proxy.CGLIBLazyInitializer.getProxyFactory(CGLIBLazyInitializer.java:126)

at org.hibernate.proxy.CGLIBProxyFactory.postInstantiate(CGLIBProxyFactory.java:41)

at org.hibernate.tuple.PojoEntityTuplizer.buildProxyFactory(PojoEntityTuplizer.java:161)

at org.hibernate.tuple.AbstractEntityTuplizer.<init>(AbstractEntityTuplizer.java:131)

at org.hibernate.tuple.PojoEntityTuplizer.<init>(PojoEntityTuplizer.java:55)

at org.hibernate.tuple.TuplizerLookup.create(TuplizerLookup.java:64)

at org.hibernate.tuple.EntityMetamodel.<init>(EntityMetamodel.java:257)

at org.hibernate.persister.entity.AbstractEntityPersister.<init>(AbstractEntityPersister.java:412)

at org.hibernate.persister.entity.SingleTableEntityPersister.<init>(SingleTableEntityPersister.java:108)

at org.hibernate.persister.PersisterFactory.createClassPersister(PersisterFactory.java:55)

at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:216)

at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1176)

at hibernate.ch05.HibernateSessionFactory.<clinit>(HibernateSessionFactory.java:31)

at hibernate.ch05.HiloTest.save(HiloTest.java:13)

at hibernate.ch05.HiloTest.main(HiloTest.java:47)

Caused by: java.lang.reflect.InvocationTargetException

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:597)

at net.sf.cglib.core.ReflectUtils.defineClass(ReflectUtils.java:384)

at net.sf.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:219)

... 17 more

Caused by: java.lang.SecurityException: class "hibernate.ch05.section02.SC$$EnhancerByCGLIB$$daf9d65b"'s signer information does not match signer information of other classes in the same package

at java.lang.ClassLoader.checkCerts(ClassLoader.java:776)

at java.lang.ClassLoader.preDefineClass(ClassLoader.java:488)

at java.lang.ClassLoader.defineClass(ClassLoader.java:615)

... 23 more

在Google试了很多方法都没有解决，最后修改了hbm.xml里这句：

<class name="hibernate.ch05.section02.SC" table="ch05_sec02_sc" catalog="sxpres">

改成：

<class name="hibernate.ch05.section02.SC" table="ch05_sec02_sc" catalog="sxpres" lazy="false">

具体的原因还不确定，网上有个朋友对这个字段的说明是：

1---lazy="false"时，用Session.load()方法加载一个Customer对象时，就执行了SQL语句,而后面对Customer的调用,都是直接从最开始执行的SQL语句得到的结果中取值,不再执行SQL语句.

2---lazy="true"时,用Session.load()方法加载一个Customer对象时，不执行SQL语句,而后面对Customer的调用时,才会执行相应的SQL语句.