1
嵌入式我有以下的模型類:在DataNucleus將
@Entity
public class A {
private B b;
}
@Embeddable
public class B {
...
}
我使用Spring MVC中,控制器標註有@Transactional和我指定了(其中包括)
datanucleus.detachAllOnCommit=true
datanucleus.detachAllOnClose=true
datanucleus.detachState=all
datanucleus.copyOnAttach=true
datanucleus.attachSameDatastore=true
datanucleus.maxFetchDepth=2
以下DataNucleus將性能
在視圖(JSP),當交易應該是在和對象分開,如果我嘗試訪問${a.b.whatever}
我得到這個錯誤
javax.jdo.JDODetachedFieldAccessException: You have just attempted to access field "b" yet this field was not detached when you detached the object. Either dont access this field, or detach it when detaching the object.
A.jdoGetb(A.java)
A.getB(A.java)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:597)
javax.el.BeanELResolver.getValue(BeanELResolver.java:62)
javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54)
org.apache.el.parser.AstValue.getValue(AstValue.java:123)
org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:935)
...
我在使用DataNucleus 3.1.3和MySQL。
任何想法爲什麼這個以及如何修復它?