hibernate实现NULLS LAST

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关于 hibernate 查询中实现order by的 NULLS LAST 和 NULLS FIRST

　1:创建一个CustomNullsFirstInterceptor类
　

package com.jnpm.util;import org.apache.tools.ant.util.StringUtils;import org.hibernate.EmptyInterceptor;import com.sun.org.apache.commons.logging.Log;import com.sun.org.apache.commons.logging.LogFactory;public class MyNullsFirstInterceptor extends EmptyInterceptor {    private static final long serialVersionUID = 1L;        private final Log logger = LogFactory.getLog(getClass());          private static final String ORDER_BY_TOKEN = "order by";        public String onPrepareStatement(String sql) {              int orderByStart = sql.toLowerCase().indexOf(ORDER_BY_TOKEN);              boolean isNeedFixNullFirst = orderByStart > -1;              if (!isNeedFixNullFirst) {                  return super.onPrepareStatement(sql);              }              sql = StringUtils.replace(sql, " DESC ", " DESC NULLS LAST ");              sql = StringUtils.replace(sql, " DESC)", " DESC NULLS LAST)");              sql = StringUtils.replace(sql, " ASC ", " ASC NULLS LAST ");              sql = StringUtils.replace(sql, " ASC)", " ASC NULLS LAST)");            logger.debug(sql);              return super.onPrepareStatement(sql);        }}

2：加入配置
applicationContext.xml

    <bean id="sessionFactory"        class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">        <property name="configLocations">            <list>            <value>classpath:*.cfg.xml</value>            </list>        </property>        <property name="entityInterceptor">            <bean id="myNullsFirstInterceptor"   　　　　　　　　　　　class="com.jnpm.util.MyNullsFirstInterceptor" />    　　</property>    </bean>

原文：http://czpae86.iteye.com/blog/1574915

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