springMVC中通用的分页配置

于 2017-10-12 17:46:31 发布
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分类专栏： springmvc 个人 文章标签： spring mvc 分页 mybatis
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本文链接：https://blog.youkuaiyun.com/yufeng005/article/details/78217770
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在前面的文章中，我们一步步完成了springmvc的maven工程的搭建，整合mybatis,日志,等操作，本文在此基础上继续添加通用的分页操作，并贴出源码供给参考。

下面先讲解本文通用的分页配置，其实通用目前仅支持oracle和mysql的两大主流数据库分页

一，此前的项目下建立新的实体类Page，并添加util包新增几个工具类，最后修改我们原先的mybatis-config.xml配置文件即可



page.java：用于封装分页的实体类

package com.test.entity;

import com.test.util.PageData;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;



/**
 * 分页类
 * @author yufeng
 * 创建时间：2017-10-12
 */
public class Page implements Serializable
{

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    private int showCount = 5; //每页显示记录数,默认为5条

    private int totalPage; //总页数

    private int totalResult; //总记录数

    private int currentPage; //当前页

    private int currentResult; //当前记录起始索引

    private boolean entityOrField; //true:需要分页的地方，传入的参数就是Page实体；false:需要分页的地方，传入的参数所代表的实体拥有Page属性

    private String pageStr; //最终页面显示的底部翻页导航，详细见：getPageStr();

    private String formName;//分页时所要提交的form的名字

    private PageData pd = new PageData();

    private List<PageData> list = new ArrayList<PageData>();

    public int getTotalPage()
    {
        if (totalResult % showCount == 0)
            totalPage = totalResult / showCount;
        else
            totalPage = totalResult / showCount + 1;
        return totalPage;
    }

    public void setTotalPage(int totalPage)
    {
        this.totalPage = totalPage;
    }

    public int getTotalResult()
    {
        return totalResult;
    }

    public void setTotalResult(int totalResult)
    {
        this.totalResult = totalResult;
    }

    public int getCurrentPage()
    {
        if (currentPage <= 0)
            currentPage = 1;
        if (currentPage > getTotalPage())
            currentPage = getTotalPage();
        return currentPage;
    }

    public void setCurrentPage(int currentPage)
    {
        this.currentPage = currentPage;
    }

    //拼接分页 页面及JS函数
    public String getPageStr()
    {
        StringBuffer sb = new StringBuffer();
        if(totalResult>0){
            sb.append(" <ul class=\"fanyecontrol\">\n");
            if(currentPage==1){                
                sb.append(" <li class=\"fyclicked\"><a>首页</a></li>\n");
                sb.append(" <li class=\"fyclicked\"><a>上一页</a></li>\n");
            }else{
                sb.append(" <li style=\"cursor:pointer;\" class=\"fyactive\"><a οnclick=\"nextPage(1)\">首页</a></li>\n");
                sb.append(" <li style=\"cursor:pointer;\" class=\"fyactive\"><a οnclick=\"nextPage("+(currentPage-1)+")\">上一页</a></li>\n");
            }
            int showTag = 5;//分页标签显示数量
            int startTag = 1;
            if(currentPage>showTag){
                startTag = currentPage-1;
            }
            int endTag = startTag+showTag-1;
            for(int i=startTag; i<=totalPage && i<=endTag; i++){
                if(currentPage==i){
                    sb.append("<li class=\"fyonclick\"><a>"+i+"</a></li>\n");
                }else{
                    sb.append(" <li style=\"cursor:pointer;\" class=\"fyactive\"><a οnclick=\"nextPage("+i+")\">"+i+"</a></li>\n");
                }
            }
            if(currentPage==totalPage){
                sb.append(" <li class=\"fyclicked\"><a>下一页</a></li>\n");
                sb.append(" <li class=\"fyclicked\"><a>末页</a></li>\n");
            }else{
                sb.append(" <li style=\"cursor:pointer;\" class=\"fyactive\"><a οnclick=\"nextPage("+(currentPage+1)+")\">下一页</a></li>\n");
                sb.append(" <li style=\"cursor:pointer;\" class=\"fyactive\"><a οnclick=\"nextPage("+totalPage+")\">末页</a></li>\n");
            }
            sb.append(" <li>共<span>"+totalPage+"</span>页</li>\n");
            sb.append(" <li>到第<input type=\"number\" value=\"\" id=\"toGoPage\" class=\"selectpage\"/>页</li>\n");
            sb.append(" <li class=\"surebtn\"><a οnclick=\"toTZ();\">确定</a></li>\n");
            
            sb.append("</ul>\n");
            sb.append("<script type=\"text/javascript\">\n");
            
            //换页函数
            sb.append("function nextPage(page){");
            sb.append(" if(true && document.forms[0]){\n");
            sb.append("     var url = document.forms[0].getAttribute(\"action\");\n");
            sb.append("     if(url.indexOf('?')>-1){url += \"&"+(entityOrField?"currentPage":"page.currentPage")+"=\";}\n");
            sb.append("     else{url += \"?"+(entityOrField?"currentPage":"page.currentPage")+"=\";}\n");
            sb.append("     url = url + page + \"&" +(entityOrField?"showCount":"page.showCount")+"="+showCount+"\";\n");
            sb.append("     document.forms[0].action = url;\n");
            sb.append("     document.forms[0].submit();\n");
            sb.append(" }else{\n");
            sb.append("     var url = document.location+'';\n");
            sb.append("     if(url.indexOf('?')>-1){\n");
            sb.append("         if(url.indexOf('currentPage')>-1){\n");
            sb.append("             var reg = /currentPage=\\d*/g;\n");
            sb.append("             url = url.replace(reg,'currentPage=');\n");
            sb.append("         }else{\n");
            sb.append("             url += \"&"+(entityOrField?"currentPage":"page.currentPage")+"=\";\n");
            sb.append("         }\n");
            sb.append("     }else{url += \"?"+(entityOrField?"currentPage":"page.currentPage")+"=\";}\n");
            sb.append("     url = url + page + \"&" +(entityOrField?"showCount":"page.showCount")+"="+showCount+"\";\n");
            sb.append("     document.location = url;\n");
            sb.append(" }\n");
            sb.append("}\n");
    
            
            //跳转函数 
            sb.append("function toTZ(){");
            sb.append("var toPaggeVlue = document.getElementById(\"toGoPage\").value;");
            sb.append("if(toPaggeVlue == ''){document.getElementById(\"toGoPage\").value=1;return;}");
            sb.append("if(isNaN(Number(toPaggeVlue))){document.getElementById(\"toGoPage\").value=1;return;}");
            sb.append("nextPage(toPaggeVlue);");
            sb.append("}\n");
            sb.append("</script>\n");
        }
        pageStr = sb.toString();
        return pageStr;
    }

    /**
     * ajax-分页
     */
    public String getAjaxPageStr()
    {
        StringBuffer sb = new StringBuffer();
        if (totalResult > 0)
        {
            sb.append(" <ul class=\"newpagination\">\n");
            if (currentPage == 1)
            {
                sb.append(" <li><a><</a></li>\n");
            }
            else
            {
                sb.append(" <li style=\"cursor:pointer;\"  οnclick=\"getPagInfo("
                          + (currentPage - 1) + ")\"><a><</a></li>\n");
            }
            int showTag = 5;//分页标签显示数量
            int startTag = 1;
            if (currentPage > showTag)
            {
                sb.append("<li>...</li>\n");
                startTag = currentPage - 1;
            }
            int endTag = startTag + showTag - 1;
            for (int i = startTag; i <= totalPage && i <= endTag; i++ )
            {
                if (currentPage == i)
                {
                    sb.append("<li class=\"active\"><a><font color='white'>"
                              + i + "</font></a></li>\n");
                }
                else
                {
                    sb.append(" <li style=\"cursor:pointer;\" οnclick=\"getPagInfo("
                              + i + ")\"><a>" + i + "</a></li>\n");
                }
            }
            if (endTag < totalPage)
            {
                sb.append("<li>...</li>\n");
            }
            if (currentPage == totalPage)
            {
                sb.append(" <li><a>></a></li>\n");
            }
            else
            {
                sb.append(" <li style=\"cursor:pointer;\" οnclick=\"getPagInfo("
                          + (currentPage + 1) + ")\"><a>></a></li>\n");
            }
            sb.append("</ul>\n");
            sb.append("<script type=\"text/javascript\">\n");

            sb.append("</script>\n");
        }
        pageStr = sb.toString();
        return pageStr;
    }

    public void setPageStr(String pageStr)
    {
        this.pageStr = pageStr;
    }

    public int getShowCount()
    {
        return showCount;
    }

    public void setShowCount(int showCount)
    {

        this.showCount = showCount;
    }

    public int getCurrentResult()
    {
        currentResult = (getCurrentPage() - 1) * getShowCount();
        if (currentResult < 0)
            currentResult = 0;
        return currentResult;
    }

    public void setCurrentResult(int currentResult)
    {
        this.currentResult = currentResult;
    }

    public boolean isEntityOrField()
    {
        return entityOrField;
    }

    public void setEntityOrField(boolean entityOrField)
    {
        this.entityOrField = entityOrField;
    }

    public String getFormName()
    {
        return formName;
    }

    public void setFormName(String formName)
    {
        this.formName = formName;
    }

    public PageData getPd()
    {
        return pd;
    }

    public void setPd(PageData pd)
    {
        this.pd = pd;
    }

    public List<PageData> getList()
    {
        return list;
    }

    public void setList(List<PageData> list)
    {
        this.list = list;
    }

}

PageData.java：封装了map类型（相当于map类型），并封装了页面http用于请求的request参数放入此类型中 

package com.test.util;

import java.io.Serializable;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

import javax.servlet.http.HttpServletRequest;

/**
 * 说明：参数封装Map
 * 创建人：yufeng
 * 修改时间 2017-10-12
 */
@SuppressWarnings("rawtypes")
public class PageData extends HashMap implements Map, Serializable {

    private static final long serialVersionUID = 1L;

    transient Map  map = null;
    HttpServletRequest request;

    @SuppressWarnings("unchecked")
    public PageData(HttpServletRequest request) {
        this.request = request;
        Map properties = request.getParameterMap();
        Map returnMap = new HashMap();
        Iterator entries = properties.entrySet().iterator();
        Map.Entry entry;
        String name = "";
        String value = "";
        while (entries.hasNext()) {
            entry = (Map.Entry) entries.next();
            name = (String) entry.getKey();
            Object valueObj = entry.getValue();
            if (null == valueObj) {
                value = "";
            } else if (valueObj instanceof String[]) {
                String[] values = (String[]) valueObj;
                for (int i = 0; i < values.length; i++) {
                    value = values[i] + ",";
                }
                value = value.substring(0, value.length() - 1);
            } else {
                value = valueObj.toString();
            }
            returnMap.put(name, value);
        }
        map = returnMap;
    }

    public PageData() {
        map = new HashMap();
    }

    @Override
    public Object get(Object key) {
        Object obj = null;
        if (map.get(key) instanceof Object[]) {
            Object[] arr = (Object[]) map.get(key);
            obj = request == null ? arr : (request.getParameter((String) key) == null ? arr : arr[0]);
        } else {
            obj = map.get(key);
        }
        return null != obj ? obj : "";
    }

    public String getString(Object key) {
        return (String) get(key);
    }

    @SuppressWarnings("unchecked")
    @Override
    public Object put(Object key, Object value) {
        return map.put(key, value);
    }

    @Override
    public Object remove(Object key) {
        return map.remove(key);
    }

    public void clear() {
        map.clear();
    }

    public boolean containsKey(Object key) {
        return map.containsKey(key);
    }

    public boolean containsValue(Object value) {
        return map.containsValue(value);
    }

    public Set entrySet() {
        return map.entrySet();
    }

    public boolean isEmpty() {
        return map.isEmpty();
    }

    public Set keySet() {
        return map.keySet();
    }

    @SuppressWarnings("unchecked")
    public void putAll(Map t) {
        map.putAll(t);
    }

    public int size() {
        return map.size();
    }

    public Collection values() {
        return map.values();
    }

}
PagePlugin.java：用于分页的插件工具类，根据不同的数据库，执行不同的查询分页方法: 

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 yufneg
* 作者单位： 
* 联系方式：
* 修改时间：2017-10-12
* @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) {
                        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.isEmpty(dialect)){
            StringBuffer pageSql = new StringBuffer();
            if("mysql".equals(dialect)){
                pageSql.append(sql);
                pageSql.append(" limit "+page.getCurrentResult()+","+page.getShowCount());
            }else if("oracle".equals(dialect)){
                String oracleSql="SELECT * FROM (SELECT A.*, ROWNUM RN FROM (";
                pageSql.append(oracleSql);
                pageSql.append(sql);
                pageSql.append(") A) WHERE RN >"+page.getCurrentResult()+" AND RN <="+(page.getCurrentResult()+page.getShowCount()));
            }
            return pageSql.toString();
        }else{
            return sql;
        }
    }
    
    public Object plugin(Object arg0) {
        return Plugin.wrap(arg0, this);
    }

    public synchronized void setProperties(Properties p) {
        dialect = p.getProperty("dialect");
        if (StringUtils.isEmpty(dialect)) {
            try {
                logger.error("PagePlugin | setProperties:|description:PropertyException",new PropertyException("dialect property is not found!"));
                throw new PropertyException("dialect property is not found!");
            } catch (PropertyException e) {
                logger.error("PagePlugin | setProperties:|description:dialect PropertyException",e);
            }
        }
        pageSqlId = p.getProperty("pageSqlId");
        if (StringUtils.isEmpty(pageSqlId)) {
            try {
                logger.error("PagePlugin | setProperties:|description:PropertyException",new PropertyException("pageSqlId property is not found!"));
                throw new PropertyException("pageSqlId property is not found!");
            } catch (PropertyException e) {
                logger.error("PagePlugin | setProperties:|description:pageSqlId PropertyException",e);
            }
        }
    }
    
}

ReflectHelper.java：反射的工具类 

package com.test.util;

import java.lang.reflect.Field;

import org.apache.log4j.Logger;

/** 
 * 说明：反射工具
 * 创建人：yufeng
 * 修改时间 2017-10-12
 * @version
 */
public class ReflectHelper {
	/**日志*/
    public static final Logger logger = Logger.getLogger(ReflectHelper.class);
	/**
	 * 获取obj对象fieldName的Field
	 * @param obj
	 * @param fieldName
	 * @return
	 */
	public static Field getFieldByFieldName(Object obj, String fieldName) {
		for (Class<?> superClass = obj.getClass(); superClass != Object.class; superClass = superClass
				.getSuperclass()) {
			try {
				return superClass.getDeclaredField(fieldName);
			} catch (NoSuchFieldException e) {
				logger.debug("ReflectHelper | getFieldByFieldName:|getFieldByFieldName Exception",e);
			}
		}
		return null;
	}

	/**
	 * 获取obj对象fieldName的属性
	 * @param obj
	 * @param fieldName
	 * @return
	 * @throws SecurityException
	 * @throws NoSuchFieldException
	 * @throws IllegalArgumentException
	 * @throws IllegalAccessException
	 */
	public static Object getValueByFieldName(Object obj, String fieldName)
			throws SecurityException, NoSuchFieldException,
			IllegalArgumentException, IllegalAccessException {
		Field field = getFieldByFieldName(obj, fieldName);
		Object value = null;
		if(field!=null){
			if (field.isAccessible()) {
				value = field.get(obj);
			} else {
				field.setAccessible(true);
				value = field.get(obj);
				field.setAccessible(false);
			}
		}
		return value;
	}

	/**
	 * 设置obj对象fieldName的属性
	 * @param obj
	 * @param fieldName
	 * @param value
	 * @throws SecurityException
	 * @throws NoSuchFieldException
	 * @throws IllegalArgumentException
	 * @throws IllegalAccessException
	 */
	public static void setValueByFieldName(Object obj, String fieldName,
			Object value) throws SecurityException, NoSuchFieldException,
			IllegalArgumentException, IllegalAccessException {
		Field field = obj.getClass().getDeclaredField(fieldName);
		if (field.isAccessible()) {
			field.set(obj, value);
		} else {
			field.setAccessible(true);
			field.set(obj, value);
			field.setAccessible(false);
		}
	}
}

最后修改我们原有的mybatis-config.xml配置文件 

<?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>  
      
    <settings>   
        <setting name="cacheEnabled" value="true" /><!-- 全局映射器启用缓存 -->     
     </settings>
     
     <typeAliases>
		<typeAlias type="com.test.util.PageData" alias="pd"/>
		<!-- 分页 -->
		<typeAlias type="com.test.entity.Page" alias="Page"/>
	</typeAliases>  
	
	<plugins>
		<plugin interceptor="com.test.util.PagePlugin">
			<property name="dialect" value="oracle"/>
			<property name="pageSqlId" value=".*listPage.*"/>
		</plugin>
	</plugins>
</configuration>

这里需要注意两点（下图红圈内）：1.根据自己的业务选择自己的数据库。


2.在mapper.xml中定义的需要分页查询方法必须含有listpage这样的关键字，这样系统会对含listpage关键字的sql进行分页，如下图


二、完成后我们重新写一个查询用户的方法，分别写接口，实现类，mapper.xml，和controller调用，最后新建一个jsp页面展示即可

我这里直接在一起的userService中新增新的方法：

UserService.java：这里返回值和参数都定义Page类型，（一般我们需要返回list）但它里面包含了我们需要查询的list集合。

public Page list(Page page)throws Exception;


UserServiceImpl.java:实现类，主要将获取到的list据转化为Page,这里的PageData和map一致，是键值对类型 

@SuppressWarnings("unchecked")
	@Override
	public Page list(Page page) throws Exception {
		List<PageData> list = (List<PageData>)dao.findForList("UserMapper.selectUserlistPage", page);
	    page.setList(list);
	    return page;
	}

us erMapper.xml：编写sql,参数是page类型，返回值是pd即pagedata 

<!-- 通过分页查询所有user -->
    <select id="selectUserlistPage"  parameterType="page" resultType="pd">  
       select user_id,username, password,name,rights,last_login,ip,status,role_id from sys_app_user  
    </select>

TestController.java 这里添加了三个方法：getList:获取集合数据,getPageData()和getRequest()方法目的是获取request请求的参数放入pagedata中。 

@RequestMapping(value="list.do")      
    public ModelAndView getList(Page page){      
        ModelAndView mv=new ModelAndView();  
        PageData pd = this.getPageData();
       List<PageData> pdlist=new ArrayList<PageData>();
        try {  
        	//查询人员列表
            page.setPd(pd);
            page.setShowCount(10);
            page = userService.list(page);
            //获取列表
            pdlist = page.getList();
            logger.info(" [TestController] [getList][success]");
        } catch (Exception e) {  
        	logger.error("[TestController] [getList][error]",e);  
        }  
        if(pdlist!=null&&pdlist.size()>0){  
             mv.addObject("list", pdlist);     
        }  
        mv.addObject("page", page);
        mv.setViewName("listUser");
        return mv;    
    }
    
    /**得到pagedata对象
     * @return
     */
    public PageData getPageData()
    {
        return new PageData(this.getRequest());
    }
    
    /**得到request对象
     * @return
     */
    public HttpServletRequest getRequest()
    {
        HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder
            .getRequestAttributes()).getRequest();
        return request;
    }

最后listUser.jsp：jsp中需要在展示和遍历list的外层包一个form表单，action则填写上面的getList()方法的请求，因为这里封装的分页通过点击的页面数通过提交表单来实现的。 

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>        
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>        
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">        
<html>        
    <head>        
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">        
        <title>test</title>  
        <style type="text/css">
        ul{
        list-style:none; /* 去掉ul前面的符号 */
	    margin: 0px; /* 与外界元素的距离为0 */
	    padding: 0px; /* 与内部元素的距离为0 */
	    width: auto; /* 宽度根据元素内容调整 */
        }
        
        ul li{
        float:left; /* 向左漂移，将竖排变为横排 */
        padding: 10px; /* 与内部元素的距离为0 */
        }
        </style>      
    </head>        
            
    <body> 
    <form action="http://localhost:9795/test/list.do" method="post" name="Form" id="Form">
    <div>      
    <c:forEach items="${list}" var="l" >  
            <h4>${l.USER_ID} | ${l.USERNAME} | ${l.NAME}</h4>  
      </c:forEach>  
    	<!--翻页控件-->
		${page.pageStr}
	</div> 
	</form>
	</body> 
</html>

最后结果：（没有优化css样式，实现了基本功能即可）点击页面的时候，注意上面地址栏参数的变化




下面贴出源码地址，源码中没有数据库脚本，自行准备数据库这块的数据

源码地址：http://download.youkuaiyun.com/download/yufeng005/10018398

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