解决Hibernate中MySQL的中文排序

最近使用mysql做一个交易网站，使用hibernate作为持久化框架。

当我使用hibernate的Order进行排序的时候，杯具发生了。中文给我乱排了。

mysql中如果需要正常按照中文排序，其中一种处理方法是

 

SELECT *
FROM BZ_COMPANY
ORDER BY CONVERT( COMPANY_NAME USING GBK ) ASC

 

 

可问题是这样就脱离hibernate了。本打算使用QBC做一些公共的方法的。

然后就去看了下hibernate中Order的实现。

 

hibernate的Order：

 

//$Id: Order.java,v 1.1 2011/05/29 18:11:15 Surui Exp $
package org.hibernate.criterion;

import java.io.Serializable;
import java.sql.Types;

import org.hibernate.Criteria;
import org.hibernate.HibernateException;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.type.Type;

/**
 * Represents an order imposed upon a <tt>Criteria</tt> result set
 * @author Gavin King
 */
public class Order implements Serializable {

	private boolean ascending;
	private boolean ignoreCase;
	private String propertyName;
	
	public String toString() {
		return propertyName + ' ' + (ascending?"asc":"desc");
	}
	
	public Order ignoreCase() {
		ignoreCase = true;
		return this;
	}

	/**
	 * Constructor for Order.
	 */
	protected Order(String propertyName, boolean ascending) {
		this.propertyName = propertyName;
		this.ascending = ascending;
	}

	/**
	 * Render the SQL fragment
	 *
	 */
	public String toSqlString(Criteria criteria, CriteriaQuery criteriaQuery) 
	throws HibernateException {
		String[] columns = criteriaQuery.getColumnsUsingProjection(criteria, propertyName);
		Type type = criteriaQuery.getTypeUsingProjection(criteria, propertyName);
		StringBuffer fragment = new StringBuffer();
		for ( int i=0; i<columns.length; i++ ) {
			SessionFactoryImplementor factory = criteriaQuery.getFactory();
			boolean lower = ignoreCase && type.sqlTypes( factory )[i]==Types.VARCHAR;
			if (lower) {
				fragment.append( factory.getDialect().getLowercaseFunction() )
					.append('(');
			}
			fragment.append( columns[i] );
			if (lower) fragment.append(')');
			fragment.append( ascending ? " asc" : " desc" );
			if ( i<columns.length-1 ) fragment.append(", ");
		}
		return fragment.toString();
	}

	/**
	 * Ascending order
	 *
	 * @param propertyName
	 * @return Order
	 */
	public static Order asc(String propertyName) {
		return new Order(propertyName, true);
	}

	/**
	 * Descending order
	 *
	 * @param propertyName
	 * @return Order
	 */
	public static Order desc(String propertyName) {
		return new Order(propertyName, false);
	}

}

 

 

重点就在toSqlString上了，QBC的Criteria也是toSqlString产生对应sql的，所以只要在这里做手脚，就能达到效果。

当然，不赞成直接改源码。

 

然后就有了GBKOrder：

 

package comm;

import java.sql.Types;

import org.hibernate.Criteria;
import org.hibernate.HibernateException;
import org.hibernate.criterion.CriteriaQuery;
import org.hibernate.criterion.Order;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.type.Type;

public class GBKOrder extends Order {
	private String encoding = "GBK";
	private boolean ascending;
	private boolean ignoreCase;
	private String propertyName;

	@Override
	public String toString() {
		return "CONVERT( " + propertyName + " USING " + encoding + " ) " + (ascending ? "asc" : "desc");
	}

	@Override
	public Order ignoreCase() {
		ignoreCase = true;
		return this;
	}

	/**
	 * Constructor for Order.
	 */
	protected GBKOrder(String propertyName, boolean ascending) {
		super(propertyName, ascending);
		this.propertyName = propertyName;
		this.ascending = ascending;
	}

	/**
	 * Constructor for Order.
	 */
	protected GBKOrder(String propertyName, String dir) {
		super(propertyName, dir.equalsIgnoreCase("ASC") ? true : false);
		ascending = dir.equalsIgnoreCase("ASC") ? true : false;
		this.propertyName = propertyName;
		this.ascending = ascending;
	}

	/**
	 * Render the SQL fragment
	 * 
	 */
	@Override
	public String toSqlString(Criteria criteria, CriteriaQuery criteriaQuery) throws HibernateException {
		String[] columns = criteriaQuery.getColumnsUsingProjection(criteria, propertyName);
		Type type = criteriaQuery.getTypeUsingProjection(criteria, propertyName);
		StringBuffer fragment = new StringBuffer();
		for (int i = 0; i < columns.length; i++) {
			SessionFactoryImplementor factory = criteriaQuery.getFactory();
			boolean lower = ignoreCase && type.sqlTypes(factory)[i] == Types.VARCHAR;
			if (lower) {
				fragment.append(factory.getDialect().getLowercaseFunction()).append('(');
			}
			fragment.append("CONVERT( " + columns[i] + " USING " + encoding + " )");
			if (lower)
				fragment.append(')');
			fragment.append(ascending ? " asc" : " desc");
			if (i < columns.length - 1)
				fragment.append(", ");
		}
		return fragment.toString();
	}

	/**
	 * Ascending order
	 * 
	 * @param propertyName
	 * @return Order
	 */
	public static Order asc(String propertyName) {
		return new GBKOrder(propertyName, true);
	}

	/**
	 * Descending order
	 * 
	 * @param propertyName
	 * @return Order
	 */
	public static Order desc(String propertyName) {
		return new GBKOrder(propertyName, false);
	}
}

 

 

使用例子：

 

	public PageControl findPage(final PageControl pageControl, final Object bean) {
		try {
			final Class clazz = bean.getClass();
			List data = (List) this.getHibernateTemplate().execute(new HibernateCallback() {
				public Object doInHibernate(Session session) throws HibernateException, SQLException {
					Criteria criteria = session.createCriteria(clazz);
					criteria.add(Example.create(bean)
							.ignoreCase()
							.enableLike(MatchMode.ANYWHERE));
					if (pageControl != null) {
						int start = pageControl.getStart();
						int limit = pageControl.getLimit();
						criteria.setFirstResult(start);
						criteria.setMaxResults(limit);
						String sort = pageControl.getSort();
						String dir = pageControl.getDir();
						if (sort != null && dir != null) {
							criteria.addOrder(dir.equalsIgnoreCase("ASC") ? GBKOrder.asc(sort) : GBKOrder.desc(sort));
						}
					}
					return criteria.list();
				}
			});
			Long totalCount = getTotalCount(bean);
			PageControl rt = new PageControl();
			rt.setData(data);
			rt.setTotalCount(totalCount);
			return rt;
		} catch (RuntimeException e) {
			log.error("find page failed", e);
			throw e;
		}
	}

当然,你有需要的话,不必写死GBK

 

附上效果图：


 

http://www.surui.cc/archives/78