【SSH异常】InvalidDataAccessApiUsageException异常-白红宇

【SSH异常】InvalidDataAccessApiUsageException异常

阅读量：6451 次

发布时间：2019-06-23

本文共 9542 字，大约阅读时间需要 31 分钟。

　　今天在整合SSH的时候，一开始我再测试的时候service层添加了注解事务调用DAO可以正常的保存，在环境中我在XML中采用了spring的OpenSessionInViewFilter解决hibernate的no-session问题(防止页面采用蓝懒加载的对象，此过滤器在访问请求前打开session，访问结束关闭session)，xml配置如下:


         
             
      
       openSessionInView
              
      
       org.springframework.orm.hibernate5.support.OpenSessionInViewFilter
          
         
             
      
       openSessionInView
              
      
       /*

　　当我在service层将事务注解注释掉之后报错，代码如下，错误如下:

错误信息:

org.springframework.dao.InvalidDataAccessApiUsageException: Write operations are not allowed in read-only mode (FlushMode.MANUAL): Turn your Session into FlushMode.COMMIT/AUTO or remove 'readOnly' marker from transaction definition.

at org.springframework.orm.hibernate5.HibernateTemplate.checkWriteOperationAllowed(HibernateTemplate.java:1126)

原因:

上面的错误:

　　　　只读模式下(FlushMode.NEVER/MANUAL)写操作不被允许：把你的Session改成FlushMode.COMMIT/AUTO或者清除事务定义中的readOnly标记。

摘自一位大牛的解释:

OpenSessionInViewFilter在getSession的时候,会把获取回来的session的flush mode 设为FlushMode.NEVER。然后把该sessionFactory绑定到TransactionSynchronizationManager，使request的整个过程都使用同一个session，在请求过后再接除该sessionFactory的绑定，最后closeSessionIfNecessary根据该session是否已和transaction绑定来决定是否关闭session。在这个过程中，若HibernateTemplate 发现自当前session有不是readOnly的transaction，就会获取到FlushMode.AUTO Session，使方法拥有写权限。也即是，如果有不是readOnly的transaction就可以由Flush.NEVER转为Flush.AUTO,拥有insert,update,delete操作权限，如果没有transaction，并且没有另外人为地设flush model的话，则doFilter的整个过程都是Flush.NEVER。所以受transaction(声明式的事务)保护的方法有写权限，没受保护的则没有。

查看OpenSessionInViewFilter源码:

* Copyright 2002-2015 the original author or authors.package org.springframework.orm.hibernate5.support;import java.io.IOException;import javax.servlet.FilterChain;import javax.servlet.ServletException;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.hibernate.FlushMode;import org.hibernate.HibernateException;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.springframework.dao.DataAccessResourceFailureException;import org.springframework.orm.hibernate5.SessionFactoryUtils;import org.springframework.orm.hibernate5.SessionHolder;import org.springframework.transaction.support.TransactionSynchronizationManager;import org.springframework.web.context.WebApplicationContext;import org.springframework.web.context.request.async.WebAsyncManager;import org.springframework.web.context.request.async.WebAsyncUtils;import org.springframework.web.context.support.WebApplicationContextUtils;import org.springframework.web.filter.OncePerRequestFilter;public class OpenSessionInViewFilter extends OncePerRequestFilter {    public static final String DEFAULT_SESSION_FACTORY_BEAN_NAME = "sessionFactory";    private String sessionFactoryBeanName = DEFAULT_SESSION_FACTORY_BEAN_NAME;    public void setSessionFactoryBeanName(String sessionFactoryBeanName) {        this.sessionFactoryBeanName = sessionFactoryBeanName;    }    protected String getSessionFactoryBeanName() {        return this.sessionFactoryBeanName;    }    @Override    protected boolean shouldNotFilterAsyncDispatch() {        return false;    }    @Override    protected boolean shouldNotFilterErrorDispatch() {        return false;    }    @Override    protected void doFilterInternal(            HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)            throws ServletException, IOException {        SessionFactory sessionFactory = lookupSessionFactory(request);        boolean participate = false;        WebAsyncManager asyncManager = WebAsyncUtils.getAsyncManager(request);        String key = getAlreadyFilteredAttributeName();        if (TransactionSynchronizationManager.hasResource(sessionFactory)) {            // Do not modify the Session: just set the participate flag.            participate = true;        }        else {            boolean isFirstRequest = !isAsyncDispatch(request);            if (isFirstRequest || !applySessionBindingInterceptor(asyncManager, key)) {                logger.debug("Opening Hibernate Session in OpenSessionInViewFilter");                Session session = openSession(sessionFactory);                SessionHolder sessionHolder = new SessionHolder(session);                TransactionSynchronizationManager.bindResource(sessionFactory, sessionHolder);                AsyncRequestInterceptor interceptor = new AsyncRequestInterceptor(sessionFactory, sessionHolder);                asyncManager.registerCallableInterceptor(key, interceptor);                asyncManager.registerDeferredResultInterceptor(key, interceptor);            }        }        try {            filterChain.doFilter(request, response);        }        finally {            if (!participate) {                SessionHolder sessionHolder =                        (SessionHolder) TransactionSynchronizationManager.unbindResource(sessionFactory);                if (!isAsyncStarted(request)) {                    logger.debug("Closing Hibernate Session in OpenSessionInViewFilter");                    SessionFactoryUtils.closeSession(sessionHolder.getSession());                }            }        }    }    protected SessionFactory lookupSessionFactory(HttpServletRequest request) {        return lookupSessionFactory();    }    protected SessionFactory lookupSessionFactory() {        if (logger.isDebugEnabled()) {            logger.debug("Using SessionFactory '" + getSessionFactoryBeanName() + "' for OpenSessionInViewFilter");        }        WebApplicationContext wac = WebApplicationContextUtils.getRequiredWebApplicationContext(getServletContext());        return wac.getBean(getSessionFactoryBeanName(), SessionFactory.class);    }    protected Session openSession(SessionFactory sessionFactory) throws DataAccessResourceFailureException {        try {            Session session = sessionFactory.openSession();            session.setFlushMode(FlushMode.MANUAL);            return session;        }        catch (HibernateException ex) {            throw new DataAccessResourceFailureException("Could not open Hibernate Session", ex);        }    }    private boolean applySessionBindingInterceptor(WebAsyncManager asyncManager, String key) {        if (asyncManager.getCallableInterceptor(key) == null) {            return false;        }        ((AsyncRequestInterceptor) asyncManager.getCallableInterceptor(key)).bindSession();        return true;    }}

　　上面将FlushMode设置MANUAL，查看FlushMode源码:

package org.hibernate;import java.util.Locale;public enum FlushMode {
        @Deprecated    NEVER ( 0 ),    MANUAL( 0 ),    COMMIT(5 ),    AUTO(10 ),    ALWAYS(20 );    private final int level;    private FlushMode(int level) {        this.level = level;    }    public boolean lessThan(FlushMode other) {        return this.level < other.level;    }    @Deprecated    public static boolean isManualFlushMode(FlushMode mode) {        return MANUAL.level == mode.level;    }    public static FlushMode interpretExternalSetting(String externalName) {        if ( externalName == null ) {            return null;        }        try {            return FlushMode.valueOf( externalName.toUpperCase(Locale.ROOT) );        }        catch ( IllegalArgumentException e ) {            throw new MappingException( "unknown FlushMode : " + externalName );        }    }}

解决办法:

　　在遇到上面错误之后我先打开@Transactional注解查看里面的源码，此注解将readonly默认置为false，所以我们在有此注解的情况下可以进行save或者update操作。源码如下:

* Copyright 2002-2015 the original author or authors.package org.springframework.transaction.annotation;import java.lang.annotation.Documented;import java.lang.annotation.ElementType;import java.lang.annotation.Inherited;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;import org.springframework.core.annotation.AliasFor;import org.springframework.transaction.TransactionDefinition;@Target({ElementType.METHOD, ElementType.TYPE})@Retention(RetentionPolicy.RUNTIME)@Inherited@Documentedpublic @interface Transactional {    @AliasFor("transactionManager")    String value() default "";    @AliasFor("value")    String transactionManager() default "";    Propagation propagation() default Propagation.REQUIRED;    Isolation isolation() default Isolation.DEFAULT;    int timeout() default TransactionDefinition.TIMEOUT_DEFAULT;    boolean readOnly() default false;    Class
     [] rollbackFor() default {};    String[] rollbackForClassName() default {};    Class
     [] noRollbackFor() default {};    String[] noRollbackForClassName() default {};}

解决办法:

　　(1)在service层打上@Transactional注解，现在想想这个设计还挺合理，无形之中要求我们打上注解。

　　(2)重写上面的过滤器,将打开session的FlushMode设为AUTO:（不推荐这种，因为在进行DML操作的时候最好加上事务控制，防止造成数据库异常）

package cn.qlq.filter;import org.hibernate.FlushMode;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.springframework.dao.DataAccessResourceFailureException;import org.springframework.orm.hibernate5.support.OpenSessionInViewFilter;/** * 重写过滤器去掉session的默认只读属性 * @author liqiang * */public class MyOpenSessionInViewFilter extends OpenSessionInViewFilter {    @Override    protected Session openSession(SessionFactory sessionFactory) throws DataAccessResourceFailureException {        Session session = sessionFactory.openSession();        session.setFlushMode(FlushMode.AUTO);        return session;    }}

web.xml配置:


         
             
      
       myOpenSessionInView
              
      
       cn.qlq.filter.MyOpenSessionInViewFilter
          
         
             
      
       myOpenSessionInView
              
      
       /*

FlushMode.COMMIT/AUTO

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