springmvc+mybatis+分页整合

package com.test.util; import java.lang.reflect.Field; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.List; import java.util.Properties; import javax.xml.bind.PropertyException; import org.apache.ibatis.executor.ErrorContext; import org.apache.ibatis.executor.ExecutorException; import org.apache.ibatis.executor.statement.BaseStatementHandler; import org.apache.ibatis.executor.statement.RoutingStatementHandler; import org.apache.ibatis.executor.statement.StatementHandler; import org.apache.ibatis.mapping.BoundSql; import org.apache.ibatis.mapping.MappedStatement; import org.apache.ibatis.mapping.ParameterMapping; import org.apache.ibatis.mapping.ParameterMode; 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.MetaObject; import org.apache.ibatis.reflection.property.PropertyTokenizer; import org.apache.ibatis.scripting.xmltags.ForEachSqlNode; import org.apache.ibatis.session.Configuration; import org.apache.ibatis.type.TypeHandler; import org.apache.ibatis.type.TypeHandlerRegistry; import org.apache.log4j.Logger; import org.springframework.util.StringUtils; import com.test.entity.Page; /** * * 类名称：分页插件 * 类描述： * @author zte * 作者单位： * 联系方式： * 修改时间：2016年2月1日 * @version 1.0 */ @Intercepts({@Signature(type=StatementHandler.class,method="prepare",args={Connection.class})}) public class PagePlugin implements Interceptor { private static String dialect = ""; //数据库方言 private static String pageSqlId = ""; //mapper.xml中需要拦截的ID(正则匹配) private static final Logger logger = Logger.getLogger(PagePlugin.class); public Object intercept(Invocation ivk) throws Throwable { if(ivk.getTarget() instanceof RoutingStatementHandler){ RoutingStatementHandler statementHandler = (RoutingStatementHandler)ivk.getTarget(); BaseStatementHandler delegate = (BaseStatementHandler) ReflectHelper.getValueByFieldName(statementHandler, "delegate"); MappedStatement mappedStatement = (MappedStatement) ReflectHelper.getValueByFieldName(delegate, "mappedStatement"); if(mappedStatement.getId().matches(pageSqlId)){ //拦截需要分页的SQL BoundSql boundSql = delegate.getBoundSql(); Object parameterObject = boundSql.getParameterObject();//分页SQL<select>中parameterType属性对应的实体参数，即Mapper接口中执行分页方法的参数,该参数不得为空 if(parameterObject==null){ throw new NullPointerException("parameterObject尚未实例化！"); }else{ Connection connection = (Connection) ivk.getArgs()[0]; String sql = boundSql.getSql(); //String countSql = "select count(0) from (" + sql+ ") as tmp_count"; //记录统计 String fhsql = sql; String countSql = "select count(0) from (" + fhsql+ ") tmp_count"; //记录统计 == oracle 加 as 报错(SQL command not properly ended) PreparedStatement countStmt = connection.prepareStatement(countSql); BoundSql countBS = new BoundSql(mappedStatement.getConfiguration(),countSql,boundSql.getParameterMappings(),parameterObject); setParameters(countStmt,mappedStatement,countBS,parameterObject); ResultSet rs = countStmt.executeQuery(); int count = 0; if (rs.next()) { count = rs.getInt(1); } rs.close(); countStmt.close(); Page page = null; if(parameterObject instanceof Page){ //参数就是Page实体 page = (Page) parameterObject; page.setEntityOrField(true); page.setTotalResult(count); }else{ //参数为某个实体，该实体拥有Page属性 Field pageField = ReflectHelper.getFieldByFieldName(parameterObject,"page"); if(pageField!=null){ page = (Page) ReflectHelper.getValueByFieldName(parameterObject,"page"); if(page==null) page = new Page(); page.setEntityOrField(false); page.setTotalResult(count); ReflectHelper.setValueByFieldName(parameterObject,"page", page); //通过反射，对实体对象设置分页对象 }else{ throw new NoSuchFieldException(parameterObject.getClass().getName()+"不存在 page 属性！"); } } String pageSql = generatePageSql(sql,page); ReflectHelper.setValueByFieldName(boundSql, "sql", pageSql); //将分页sql语句反射回BoundSql. } } } return ivk.proceed(); } /** * 对SQL参数(?)设值,参考org.apache.ibatis.executor.parameter.DefaultParameterHandler * @param ps * @param mappedStatement * @param boundSql * @param parameterObject * @throws SQLException */ @SuppressWarnings({"rawtypes", "unchecked"}) private void setParameters(PreparedStatement ps,MappedStatement mappedStatement,BoundSql boundSql,Object parameterObject) throws SQLException { ErrorContext.instance().activity("setting parameters").object(mappedStatement.getParameterMap().getId()); List<ParameterMapping> parameterMappings = boundSql.getParameterMappings(); if (parameterMappings != null) { Configuration configuration = mappedStatement.getConfiguration(); TypeHandlerRegistry typeHandlerRegistry = configuration.getTypeHandlerRegistry(); MetaObject metaObject = parameterObject == null ? null: configuration.newMetaObject(parameterObject); for (int i = 0; i < parameterMappings.size(); i++) { ParameterMapping parameterMapping = parameterMappings.get(i); if (parameterMapping.getMode() != ParameterMode.OUT) { Object value; String propertyName = parameterMapping.getProperty(); PropertyTokenizer prop = new PropertyTokenizer(propertyName); if (parameterObject == null) { value = null; } else if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) { value = parameterObject; } else if (boundSql.hasAdditionalParameter(propertyName)) { value = boundSql.getAdditionalParameter(propertyName); } else if (propertyName.startsWith(ForEachSqlNode.ITEM_PREFIX)&& boundSql.hasAdditionalParameter(prop.getName())) { value = boundSql.getAdditionalParameter(prop.getName()); if (value != null) { value = configuration.newMetaObject(value).getValue(propertyName.substring(prop.getName().length())); } } else { value = metaObject == null ? null : metaObject.getValue(propertyName); } TypeHandler typeHandler = parameterMapping.getTypeHandler(); if (typeHandler == null) {