1.封装分页Page类
package com.framework.common.page.impl;
import java.io.Serializable;
import com.framework.common.page.IPage;
/**
*
*
*
*/
public abstract class BasePage implements IPage, Serializable {
/**
*
*/
private static final long serialVersionUID = -3623448612757790359L;
public static int DEFAULT_PAGE_SIZE = 20;
private int pageSize = DEFAULT_PAGE_SIZE;
private int currentResult;
private int totalPage;
private int currentPage = 1;
private int totalCount = -1;
public BasePage(int currentPage, int pageSize, int totalCount) {
this.currentPage = currentPage;
this.pageSize = pageSize;
this.totalCount = totalCount;
}
public int getTotalCount() {
return this.totalCount;
}
public void setTotalCount(int totalCount) {
if (totalCount < 0) {
this.totalCount = 0;
return;
}
this.totalCount = totalCount;
}
public BasePage() {
}
public int getFirstResult() {
return (this.currentPage - 1) * this.pageSize;
}
public void setPageSize(int pageSize) {
if (pageSize < 0) {
this.pageSize = DEFAULT_PAGE_SIZE;
return;
}
this.pageSize = pageSize;
}
public int getTotalPage() {
if (this.totalPage <= 0) {
this.totalPage = (this.totalCount / this.pageSize);
if ((this.totalPage == 0) || (this.totalCount % this.pageSize != 0)) {
this.totalPage += 1;
}
}
return this.totalPage;
}
public int getPageSize() {
return this.pageSize;
}
public void setPageNo(int currentPage) {
this.currentPage = currentPage;
}
public int getPageNo() {
return this.currentPage;
}
public boolean isFirstPage() {
return this.currentPage <= 1;
}
public boolean isLastPage() {
return this.currentPage >= getTotalPage();
}
public int getNextPage() {
if (isLastPage()) {
return this.currentPage;
}
return this.currentPage + 1;
}
public int getCurrentResult() {
this.currentResult = ((getPageNo() - 1) * getPageSize());
if (this.currentResult < 0) {
this.currentResult = 0;
}
return this.currentResult;
}
public int getPrePage() {
if (isFirstPage()) {
return this.currentPage;
}
return this.currentPage - 1;
}
}package com.framework.common.page.impl;
import java.util.List;
/**
*
*
*
*/
public class Page extends BasePage {
/**
*
*/
private static final long serialVersionUID = -970177928709377315L;
public static ThreadLocal<Page> threadLocal = new ThreadLocal<Page>();
private List<?> data;
public Page() {
}
public Page(int currentPage, int pageSize, int totalCount) {
super(currentPage, pageSize, totalCount);
}
public Page(int currentPage, int pageSize, int totalCount, List<?> data) {
super(currentPage, pageSize, totalCount);
this.data = data;
}
public List<?> getData() {
return data;
}
public void setData(List<?> data) {
this.data = data;
}
}2.封装分页插件
package com.framework.common.page.plugin;
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.commons.lang3.StringUtils;
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.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.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 com.framework.common.page.impl.Page;
import com.framework.common.utils.ReflectUtil;
/**
*
*
*
*/
@Intercepts({ @org.apache.ibatis.plugin.Signature(type = org.apache.ibatis.executor.statement.StatementHandler.class, method = "prepare", args = { Connection.class }) })
public class PagePlugin implements Interceptor {
private String dialect = "";
private String pageSqlId = "";
@Override
public Object intercept(Invocation invocation) throws Throwable {
if (invocation.getTarget() instanceof RoutingStatementHandler) {
BaseStatementHandler delegate = (BaseStatementHandler) ReflectUtil
.getValueByFieldName(
(RoutingStatementHandler) invocation.getTarget(),
"delegate");
MappedStatement mappedStatement = (MappedStatement) ReflectUtil
.getValueByFieldName(delegate,
"mappedStatement");
Page page = Page.threadLocal.get();
if (page == null) {
page = new Page();
Page.threadLocal.set(page);
}
if (mappedStatement.getId().matches(".*(" + this.pageSqlId + ")$") && page.getPageSize() > 0) {
BoundSql boundSql = delegate.getBoundSql();
Object parameterObject = boundSql.getParameterObject();
String sql = boundSql.getSql();
String countSqlId = mappedStatement.getId().replaceAll(pageSqlId, "Count");
MappedStatement countMappedStatement = null;
if (mappedStatement.getConfiguration().hasStatement(countSqlId)) {
countMappedStatement = mappedStatement.getConfiguration().getMappedStatement(countSqlId);
}
String countSql = null;
if (countMappedStatement != null) {
countSql = countMappedStatement.getBoundSql(parameterObject).getSql();
} else {
countSql = "SELECT COUNT(1) FROM (" + sql + ") T_COUNT";
}
int totalCount = 0;
PreparedStatement countStmt = null;
ResultSet resultSet = null;
try {
Connection connection = (Connection) invocation.getArgs()[0];
countStmt = connection.prepareStatement(countSql);
BoundSql countBoundSql = new BoundSql(mappedStatement.getConfiguration(), countSql, boundSql.getParameterMappings(), parameterObject);
setParameters(countStmt, mappedStatement, countBoundSql, parameterObject);
resultSet = countStmt.executeQuery();
if(resultSet.next()) {
totalCount = resultSet.getInt(1);
}
} catch (Exception e) {
throw e;
} finally {
try {
if (resultSet != null) {
resultSet.close();
}
} finally {
if (countStmt != null) {
countStmt.close();
}
}
}
page.setTotalCount(totalCount);
ReflectUtil.setValueByFieldName(boundSql, "sql", generatePageSql(sql,page));
}
}
return invocation.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
*/
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) {
throw new ExecutorException("There was no TypeHandler found for parameter "+ propertyName + " of statement "+ mappedStatement.getId());
}
typeHandler.setParameter(ps, i + 1, value, parameterMapping.getJdbcType());
}
}
}
}
/**
* 根据数据库方言，生成特定的分页sql
* @param sql
* @param page
* @return
*/
private String generatePageSql(String sql,Page page){
if(page!=null && StringUtils.isNotBlank(dialect)){
StringBuffer pageSql = new StringBuffer();
if("mysql".equals(dialect)){
pageSql.append(sql);
pageSql.append(" LIMIT "+page.getCurrentResult()+","+page.getPageSize());
}else if("oracle".equals(dialect)){
pageSql.append("SELECT * FROM (SELECT TMP_TB.*,ROWNUM ROW_ID FROM (");
pageSql.append(sql);
pageSql.append(") AS TMP_TB WHERE ROWNUM <= ");
pageSql.append(page.getCurrentResult()+page.getPageSize());
pageSql.append(") WHERE ROW_ID > ");
pageSql.append(page.getCurrentResult());
}
return pageSql.toString();
}else{
return sql;
}
}
@Override
public Object plugin(Object target) {
return Plugin.wrap(target, this);
}
@Override
public void setProperties(Properties properties) {
try {
if (StringUtils.isEmpty(this.dialect = properties
.getProperty("dialect"))) {
throw new PropertyException("dialect property is not found!");
}
if (StringUtils.isEmpty(this.pageSqlId = properties
.getProperty("pageSqlId"))) {
throw new PropertyException("pageSqlId property is not found!");
}
} catch (PropertyException e) {
e.printStackTrace();
}
}
}3.MyBatis配置文件:mybatis-config.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD SQL Map Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<plugins>
<plugin interceptor="com.framework.common.page.plugin.PagePlugin">
<property name="dialect" value="mysql" />
<property name="pageSqlId" value="ByPage" />
</plugin>
</plugins>
</configuration>4.分页拦截器
package com.framework.common.page.interceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.lang3.math.NumberUtils;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
import com.framework.common.page.impl.Page;
/**
*
* 14 *
*/
public class PageInterceptor extends HandlerInterceptorAdapter {
@Override
public void postHandle(HttpServletRequest request,
HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
super.postHandle(request, response, handler, modelAndView);
Page page = Page.threadLocal.get();
if (page != null) {
request.setAttribute("page", page);
}
Page.threadLocal.remove();
}
@Override
public boolean preHandle(HttpServletRequest request,
HttpServletResponse response, Object handler) throws Exception {
String pageSize = request.getParameter("pageSize");
String pageNo = request.getParameter("pageNo");
Page page = new Page();
if (NumberUtils.isNumber(pageSize)) {
page.setPageSize(NumberUtils.toInt(pageSize));
}
if (NumberUtils.isNumber(pageNo)) {
page.setPageNo(NumberUtils.toInt(pageNo));
}
Page.threadLocal.set(page);
return true;
}
}5.Spring配置
<!-- ===================================================================
- Load property file
- =================================================================== -->
<context:property-placeholder location="classpath:application.properties" />
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="configLocation" value="classpath:mybatis-config.xml" />
<property name="mapperLocations">
<list>
<value>classpath:/com/framework/mapper/**/*Mapper.xml</value>
</list>
</property>
</bean>
<!-- ===================================================================
- 通过扫描的模式，扫描目录下所有的dao， 根据对应的mapper.xml为其生成代理类
- =================================================================== -->
<bean id="mapperScannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.framework.dao" />
<property name="processPropertyPlaceHolders" value="true" />
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />
</bean>
6.SpringMVC配置拦截器
<!-- 分页拦截器 -->
<bean id="pageInterceptor" class="com.framework.common.page.interceptor.PageInterceptor"></bean>
<!-- 配置拦截器 -->
<bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping">
<property name="interceptors">
<list>
<ref bean="pageInterceptor" />
</list>
</property>
</bean>更多Java简单实现SpringMVC+MyBatis分页插件相关文章请关注PHP中文网！
