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本项目主要弥补在使用mybatis3+springmvc+jquery easyui快速搭建web应用系统是遇到的框架不足. 主要工作包括： 1，扩展了ApplicationContextAware，通过单例注入spring容器，提供spring容器外的bean获取方法 2，扩展了apache shiro框架，统一了安全结构 3，扩展了mybatis3拦截器，在两个拦截器中自动完成分页注入，实现内存分页。 4，分页设计数据库方言 5，提供了一个easyuigrid的模型 6，提供了java泛型的jstl 7， xml工具包等一些小工具

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package net.sourceforge.orm.mybatis;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.Properties;

import net.sourceforge.orm.dialect.Dialect;
import net.sourceforge.orm.dialect.DialectFactory;

import org.apache.ibatis.executor.parameter.ParameterHandler;
import org.apache.ibatis.executor.statement.StatementHandler;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Plugin;
import org.apache.ibatis.plugin.Signature;
import org.apache.ibatis.reflection.DefaultReflectorFactory;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.reflection.factory.DefaultObjectFactory;
import org.apache.ibatis.reflection.factory.ObjectFactory;
import org.apache.ibatis.reflection.wrapper.DefaultObjectWrapperFactory;
import org.apache.ibatis.reflection.wrapper.ObjectWrapperFactory;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.RowBounds;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author [email protected]
 **/
@Intercepts({ @Signature(type = StatementHandler.class, method = "prepare", args = { Connection.class, Integer.class }) })
public class PaginationStatementHandlerInterceptor implements Interceptor {

	private final static Logger logger = LoggerFactory.getLogger(PaginationStatementHandlerInterceptor.class);

	private static final ObjectFactory DEFAULT_OBJECT_FACTORY = new DefaultObjectFactory();
	private static final ObjectWrapperFactory DEFAULT_OBJECT_WRAPPER_FACTORY = new DefaultObjectWrapperFactory();
	private static final DefaultReflectorFactory DEFAULT_REFLECTOR_FACTORY = new DefaultReflectorFactory();

	@Override
	public Object intercept(Invocation invocation) throws Throwable {
		StatementHandler statementHandler = (StatementHandler) invocation.getTarget();
		ParameterHandler parameterHandler = statementHandler.getParameterHandler();
		BoundSql boundSql = statementHandler.getBoundSql();

		MetaObject metaStatementHandler = MetaObject.forObject(statementHandler, DEFAULT_OBJECT_FACTORY, DEFAULT_OBJECT_WRAPPER_FACTORY, DEFAULT_REFLECTOR_FACTORY);
		RowBounds rowBounds = (RowBounds) metaStatementHandler.getValue("delegate.rowBounds");
		// 没有分页参数
		if (rowBounds == null || rowBounds == RowBounds.DEFAULT) {
			return invocation.proceed();
		}

		Configuration configuration = (Configuration) metaStatementHandler.getValue("delegate.configuration");
		Dialect dialect = DialectFactory.buildDialect(configuration);
		String originalSql = (String) metaStatementHandler.getValue("delegate.boundSql.sql");
		// 获取总记录数
		Page page = (Page) rowBounds;
		String countSql = dialect.getCountString(originalSql);
		Connection connection = (Connection) invocation.getArgs()[0];
		int total = getTotal(parameterHandler, connection, countSql);
		page.setTotalCount(total);

		// 设置物理分页语句
		metaStatementHandler.setValue("delegate.boundSql.sql",
				dialect.getLimitString(originalSql, page.getOffset(), page.getLimit()));
		// 屏蔽mybatis原有分页
		metaStatementHandler.setValue("delegate.rowBounds.offset", RowBounds.NO_ROW_OFFSET);
		metaStatementHandler.setValue("delegate.rowBounds.limit", RowBounds.NO_ROW_LIMIT);
		if (logger.isDebugEnabled()) {
			logger.debug("paging SQL : " + boundSql.getSql());
		}
		return invocation.proceed();
	}

	@Override
	public Object plugin(Object target) {
		return Plugin.wrap(target, this);
	}

	@Override
	public void setProperties(Properties properties) {
	}

	/**
	 * 获取总计录
	 * 
	 * @param parameterHandler
	 * @param connection
	 * @param countSql
	 * @return
	 * @throws Exception
	 */
	private int getTotal(ParameterHandler parameterHandler, Connection connection, String countSql) throws Exception {
		// MetaObject metaStatementHandler =
		// MetaObject.forObject(parameterHandler);
		// Object parameterObject =
		// metaStatementHandler.getValue("parameterObject");
		// TODO 缓存具有相同SQL语句和参数的总数
		PreparedStatement prepareStatement = connection.prepareStatement(countSql);
		parameterHandler.setParameters(prepareStatement);
		ResultSet rs = prepareStatement.executeQuery();
		int count = 0;
		if (rs.next()) {
			count = rs.getInt(1);
		}
		rs.close();
		prepareStatement.close();
		return count;
	}
}