java - Struts2Jsonの結果HibernateLazyInitialization-Hibernateセッション内で逆シリアル化する方法

Question

LazyInitializationExceptionStruts2でのjsonの結果を回避するために、Hibernateセッション/トランザクションインターセプターを実装しようとしていますが、とにかくこの例外が発生します。

245968 [http-8080-7] ERROR util.HibernateEndTransInterceptor  - org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: java.lang.reflect.InvocationTargetException
org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: java.lang.reflect.InvocationTargetException
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:238)
    at org.apache.struts2.json.JSONWriter.processCustom(JSONWriter.java:171)
    at org.apache.struts2.json.JSONWriter.process(JSONWriter.java:161)
    at org.apache.struts2.json.JSONWriter.value(JSONWriter.java:127)
    at org.apache.struts2.json.JSONWriter.write(JSONWriter.java:95)
    at org.apache.struts2.json.JSONUtil.serialize(JSONUtil.java:116)
    at org.apache.struts2.json.JSONResult.createJSONString(JSONResult.java:196)
    at org.apache.struts2.json.JSONResult.execute(JSONResult.java:170)
    at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:374)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:278)
    at util.HibernateEndTransInterceptor.intercept(HibernateEndTransInterceptor.java:55)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
    at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:236)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:236)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:90)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:192)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at util.HibernateBeginTransInterceptor.intercept(HibernateBeginTransInterceptor.java:32)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at util.LoginInterceptor.intercept(LoginInterceptor.java:36)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
    at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:511)
    at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
    at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
    at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:831)
    at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:652)
    at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1203)
    at java.lang.Thread.run(Thread.java:722)
Caused by: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: java.lang.reflect.InvocationTargetException
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:238)
    at org.apache.struts2.json.JSONWriter.processCustom(JSONWriter.java:171)
    at org.apache.struts2.json.JSONWriter.process(JSONWriter.java:161)
    at org.apache.struts2.json.JSONWriter.value(JSONWriter.java:127)
    at org.apache.struts2.json.JSONWriter.add(JSONWriter.java:363)
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:223)
    ... 73 more
Caused by: org.apache.struts2.json.JSONException: org.apache.struts2.json.JSONException: java.lang.reflect.InvocationTargetException
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:238)
    at org.apache.struts2.json.JSONWriter.processCustom(JSONWriter.java:171)
    at org.apache.struts2.json.JSONWriter.process(JSONWriter.java:161)
    at org.apache.struts2.json.JSONWriter.value(JSONWriter.java:127)
    at org.apache.struts2.json.JSONWriter.add(JSONWriter.java:363)
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:223)
    ... 78 more
Caused by: org.apache.struts2.json.JSONException: java.lang.reflect.InvocationTargetException
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:238)
    at org.apache.struts2.json.JSONWriter.processCustom(JSONWriter.java:171)
    at org.apache.struts2.json.JSONWriter.process(JSONWriter.java:161)
    at org.apache.struts2.json.JSONWriter.value(JSONWriter.java:127)
    at org.apache.struts2.json.JSONWriter.add(JSONWriter.java:363)
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:223)
    ... 83 more
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at org.apache.struts2.json.JSONWriter.bean(JSONWriter.java:218)
    ... 88 more
Caused by: org.hibernate.LazyInitializationException: could not initialize proxy - no Session
    at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:165)
    at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:272)
    at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:185)
    at com.lm.model.common.Language_$$_javassist_0.getName(Language_$$_javassist_0.java)
    ... 93 more

私のインターセプターは次のようになります。

package util;

import java.util.Map;

import org.apache.log4j.Logger;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;

import util.hibernate.HibernateUtil;

import com.lm.action.ActionsConstants;
import com.lm.action.user.Constants;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;

public class HibernateEndTransInterceptor implements Interceptor, Constants, ActionsConstants {


    private static final long serialVersionUID = -8734958511612355789L;

    private static SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
    private transient Logger log = Logger.getLogger(HibernateEndTransInterceptor.class);
    private Session s=null;
    private Transaction t=null;

    @Override
    public void destroy() {
    }

    @Override
    public void init() {
    }

    @Override
    public String intercept(final ActionInvocation invocation) throws Exception {
        /*invocation.addPreResultListener(new PreResultListener() {

            @Override
            public void beforeResult(ActionInvocation arg0, String arg1) {
                Map<String, ResultConfig> resultsMap = invocation.getProxy().getConfig().getResults();
                //ResultConfig finalResultConfig = resultsMap.get(resultCode);

            }
        });*/


        Map<String,Object> strutsSession = invocation.getInvocationContext().getSession();
        String res=null;
        try {
            s=sessionFactory.openSession();
            t = s.beginTransaction();
            strutsSession.put("hibernateSession", s);
            strutsSession.put("hibernateTransaction", t);
            res=invocation.invoke();
            t.commit();
        } catch (Throwable t2) {
            log.error(t2,t2);
            try {
                t.rollback();
            } catch (Throwable t3) {
                log.error(t3,t3);
            }
        } finally {
            try {
                s.close();
            } catch (Throwable t) {
                log.error(t,t);
            }
            strutsSession.remove("hibernateSession");
            strutsSession.remove("hibernateTransaction");
        }
        return res;
    }

}

これは機能していません、私はLazyInitializationException前にさえ得ていますtrans.commit()そしてsession.close();

score 1 · Accepted Answer

ウィールを再実装しないでください。ビューコンセプトでオープンセッションを実装する必要がある場合は、Hibernateフルプラグインを使用してください。コレクションのLazyInitializationException配置を修正したい場合。FetchType.EAGER

score 1 · Accepted Answer

さて、ついに私はジェネリックDAO（セッションとトランザクションを含む）のインジェクションをgenericActionに追加することを解決しました。これは、怠惰な休止状態のBeanを使用するJSONResultsおよびjspで機能します。

「bmorris591」と「RomanC」への貢献に感謝します（このプラグインはすべて必要ありません）。

私は私の例を残します、私は何も忘れないことを願っています...

インターセプター構成（struts.xmlフラグメント）：

<package name="lmp" extends="struts-default,json-default">
    <interceptors>
        <interceptor name="login" class="util.LoginInterceptor"/>
        <interceptor name="hibernateSessionTransInjector" class="util.HibernateSessionTransInjectorInterceptor"/>
        <interceptor-stack name="loggingStack">
            <interceptor-ref name="login" />
            <interceptor-ref name="defaultStack" />
            <interceptor-ref name="hibernateSessionTransInjector"/>
        </interceptor-stack>
    </interceptors>

    <default-interceptor-ref name="loggingStack"/>

    <global-results>
        <result name="login" type="redirectAction">login</result>
    </global-results>
</package>
<package name="myAction" extends="lmp">

    <action name="myAction" class="com.lmp.MyAction">
        <result name="json" type="json">
            <param name="ignoreHierarchy">false</param>
        </result>
        <result name="*">/jsp/myAction.jsp</result>
    </action>
</package>

インターセプターの実装：

package util;

import org.apache.log4j.Logger;
import org.hibernate.Session;
import org.hibernate.SessionFactory;

import util.hibernate.HibernateUtil;

import com.lm.action.ActionsConstants;
import com.lm.action.user.Constants;
import com.lm.dao.DAO;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;

public class HibernateSessionTransInjectorInterceptor implements Interceptor, Constants, ActionsConstants {


    private static final long serialVersionUID = -8734958511612355789L;

    private static SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
    private transient Logger log = Logger.getLogger(HibernateSessionTransInjectorInterceptor.class);

    @Override
    public void destroy() {
    }

    @Override
    public void init() {
    }

    @Override
    public String intercept(final ActionInvocation invocation) throws Exception {
        String res=null;
        DAO dao=null;
        try {
            Session s=sessionFactory.openSession();
            dao = new DAO(s);
            dao.beginTransaction();
            **invocation.getStack().setValue("dao", dao, true);**
            res=invocation.invoke();
            boolean rollback=(Boolean)invocation.getStack().findValue("rollbackTransaction", Boolean.class);
            if (rollback)
                dao.rollBackTransaction();
            if (!dao.getT().wasRolledBack())
                dao.commitTransaction();
        } catch (Throwable t2) {
            log.error(t2,t2);
            if (dao!=null)
            try {
                dao.rollBackTransaction();
            } catch (Throwable t3) {
                log.error(t3,t3);
            }
        } finally {
            if (dao!=null)
            try {
                dao.finallyClose();
            } catch (Throwable t) {
                log.error(t,t);
            }
        }
        return res;
    }

}

UserDAOの例：

public class UserDAO extends DAO {

[...]
    public UserDAO(Session s) {
        super(s);
    }
[...]
}

GenericDAOの例：

public class DAO {

    protected static final transient Logger log = Logger.getLogger(DAO.class);

    public static SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
    public Session s = null;
    public Transaction t = null;

    public DAO(Session s) {
        this.s=s;
    }

    public void beginTransaction(Transaction t) {
        this.t=t;
    }

    private int exceptionErr=0;
    public void beginTransaction() {
        try {
            t=s.beginTransaction();
        } catch (Throwable t) {
            log.error(t,t);
        }
    }
    public void rollBackTransaction() {
        if (t!=null && t.isActive())
            t.rollback();
    }
    public void commitTransaction() {
        if (t!=null && t.isActive())
            t.commit();
    }

    public void finallyClose() {
        if (t!=null && t.isActive()) 
            t.rollback();
        if (s!=null && s.isOpen())
            s.close();
    }

    public Session getS() {
        return s;
    }

    public void setS(Session s) {
        this.s = s;
    }

    public Transaction getT() {
        return t;
    }

    public void setT(Transaction t) {
        this.t = t;
    }

}

GenericAction：

public class GenericAction extends ActionSupport  {

    private DAO dao=null;  //Interceptor injects here

    public GenericAction() {
    }

...
    @JSON(deserialize=false, serialize=false)
    public DAO getDao() {
        return dao;
    }

    @JSON(deserialize=false, serialize=false)
    public void setDao(DAO dao) {
        this.dao = dao;
    }

}

MyAction：

public class MyAction extends GenericAction {

    public MyAction() {
    }

    @Override
    public String execute() throws Exception {
        super.execute();
        UserDAO userDAO=new UserDAO(getDao().getS());
        OtherDAO otherDAO=new OtherDAO(getDao().getS());
        userDAO.loadUsers(...);
            return SUCCESS;
    }
}

score 0 · Accepted Answer

これがStruts2インターセプターである場合、これは絶対にそれを実装する方法ではありません。

アプリケーションには、すべてのリクエストに対してインターセプターの単一のインスタンスがあるため、1つのリクエストがメソッドに変数を設定し、intercept次に別のリクエストが入って、最初のリクエストがまだ処理されている間にそれらをリセットします。次に、最初のリクエストはsession.close()、2番目のリクエストのセッションの呼び出しで返されます。

インターセプターは次のようになります。

@Override
public String intercept(final ActionInvocation invocation) throws Exception {
    final Map<String, Object> strutsSession = invocation.getInvocationContext().getSession();
    String res = null;
    Session s = null;
    Transaction t = null;
    try {
        s = sessionFactory.openSession();
        t = s.beginTransaction();
        strutsSession.put("hibernateSession", s);
        strutsSession.put("hibernateTransaction", t);
        res = invocation.invoke();
        t.commit();
    } catch (Throwable t2) {
        log.error(t2, t2);
        t.rollback();
    } finally {
        s.close();
        strutsSession.remove("hibernateSession");
        strutsSession.remove("hibernateTransaction");
    }
    return res;
}

リクエスト間で共有したい場合を除いて、すべての変数がローカルであることに注意してください。

また、空のメソッドがすべてなくなるように拡張AbstractInterceptorすることをお勧めします。

java - Struts2Jsonの結果HibernateLazyInitialization-Hibernateセッション内で逆シリアル化する方法

3 に答える 3

Related

Reference