mybatis常用经典分页方法
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分页方法一：
可以查看如下代码，新建一个数据库分页基础类
package com.ssm.utils.pagination.pagebounds;
import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionUtils;
import org.springframework.beans.factory.annotation.Autowired;
import com.github.miemiedev.mybatis.paginator.domain.PageBounds;
/**
* 用于数据库分页
* 使用方法如：public class XXXServiceImpl extends BasePageService implements IXXXService {
* 然后代码中使用如：this.getPageList(XXXMapper.class,
"selectObjectListMethod", sqlmapperParams, currentPage,pageSize);
其中currentPage由网页客户端保存，每次分页+1
* @author Administrator
*
*/
public class BasePageService {
@Autowired
private SqlSessionFactoryBean sqlSessionFactoryBean;
public List<?> getPageList(Class<?> mapperClass, String sqlId,
Object sqlParameter, int pageIndex, int pageSize) {
SqlSession session = null;
try {
SqlSessionFactory sessionFactory = sqlSessionFactoryBean
.getObject();
session = sessionFactory.openSession();
if (pageIndex <= 0) {
pageIndex = 1;
}
if (pageSize <= 0) {
pageSize = 10;
}
PageBounds pageBounds = new PageBounds(pageIndex, pageSize);
List<Object> pageList = session.selectList(mapperClass.getName()
+ "." + sqlId, sqlParameter, pageBounds);
return pageList;
} catch (Exception e) {
e.printStackTrace();
} finally {
session.close();
}
return null;
}
}
分页方法2：
定义一个page基本类，用于网页与后端之间的页面传输封装
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import com.ssm.util.PageData;
public class Page {
private int isM1 = 0; // 每页显示记录数
private int isM2; // 每页显示记录数
private int showCount = 10; // 每页显示记录数
private int totalPage; // 总页数
private int totalResult; // 总记录数
private int currentPage = 1; // 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 PageData pd = new PageData();
private int begin;
private int end;
// 总行数，需要外接传入
private int rows;
public int getIsM1() {
return isM1;
}
public void setIsM1(int isM1) {
this.isM1 = isM1;
}
public int getIsM2() {
return isM2;
}
public void setIsM2(int isM2) {
this.isM2 = isM2;
}
public int getRows() {
return rows;
}
public void setRows(int rows) {
this.rows = rows;
}
public int getBegin() {
begin = (currentPage - 1) * showCount;
return begin;
}
public void setBegin(int begin) {
this.begin = begin;
}
public int getEnd() {
end = currentPage * showCount;
return end;
}
public void setEnd(int end) {
this.end = end;
}
public Page() {
// 通过page。txt设置每页显示的条数
// String xmpath =
// String.valueOf(Thread.currentThread().getContextClassLoader().getResource(""));
// // System.out.println(xmpath);
// xmpath = xmpath.substring(6)+"page.txt";
// // System.out.println(xmpath);
// this.showCount = Integer.parseInt(readTxtFile(xmpath));
}
public int getTotalPage() {
if (rows % showCount == 0)
totalPage = rows / showCount;
else
totalPage = rows / 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;
}
// 用于显示页码
public String getPageStr() {
StringBuffer sb = new StringBuffer();
if (totalResult > 0) {
sb.append(" <ul>\n");
if (currentPage == 1) {
sb.append(" <li><a>共<font color=red>" + totalResult
+ "</font>条</a></li>\n");
sb.append(" <li><input type=\"number\" value=\"\" id=\"toGoPage\" style=\"width:50px;text-align:center;float:left\" placeholder=\"页码\"/></li>\n");
sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"toTZ();\" class=\"btn btn-mini btn-success\">跳转</a></li>\n");
sb.append(" <li><a>首页</a></li>\n");
sb.append(" <li><a>上页</a></li>\n");
} else {
sb.append(" <li><a>共<font color=red>" + totalResult
+ "</font>条</a></li>\n");
sb.append(" <li><input type=\"number\" value=\"\" id=\"toGoPage\" style=\"width:35px;text-align:center;\" placeholder=\"页码\"/></li>\n");
sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"toTZ();\" class=\"btn btn-mini btn-success\">跳转</a></li>\n");
sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"nextPage(1)\">首页</a></li>\n");
sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"nextPage("
+ (currentPage - 1) + ")\">上页</a></li>\n");
}
int showTag = 3; // 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=\"current\"><a>" + i + "</a></li>\n");
else
sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"nextPage("
+ i + ")\">" + i + "</a></li>\n");
}
if (currentPage == totalPage) {
sb.append(" <li><a>下页</a></li>\n");
sb.append(" <li><a>尾页</a></li>\n");
} else {
sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"nextPage("
+ (currentPage + 1) + ")\">下页</a></li>\n");
sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"nextPage("
+ totalPage + ")\">尾页</a></li>\n");
}
sb.append(" <li><a>第" + currentPage + "页</a></li>\n");
sb.append(" <li><a>共" + totalPage + "页</a></li>\n");
// sb.append(" <li style=\"cursor:pointer;\"><a onclick=\"toTZ();\" class=\"btn btn-mini btn-success\">跳转</a></li>\n");
sb.append("</ul>\n");
sb.append("<script type=\"text/javascript\">\n");
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(" document.forms[0].action = url+page;\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(" document.location = url + page;\n");
sb.append(" }\n");
sb.append("}\n");
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;
}
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 PageData getPd() {
return pd;
}
public void setPd(PageData pd) {
this.pd = pd;
}
// 读取文件
public String readTxtFile(String filePath) {
try {
String encoding = "utf-8";
File file = new File(filePath);
if (file.isFile() && file.exists()) { // 判断文件是否存在
InputStreamReader read = new InputStreamReader(
new FileInputStream(file), encoding);// 考虑到编码格式
BufferedReader bufferedReader = new BufferedReader(read);
String lineTxt = null;
while ((lineTxt = bufferedReader.readLine()) != null) {
return lineTxt;
}
read.close();
} else {
System.out.println("找不到指定的文件");
}
} catch (Exception e) {
System.out.println("读取文件内容出错");
e.printStackTrace();
}
return "";
}
}
package com.ssm.util;
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;
public class PageData extends HashMap implements Map{
private static final long serialVersionUID = 1L;
Map map = null;
HttpServletRequest request;
//获取请求参数和请求参数值的map
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 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();
}
}
接下来可根据page定义一个更加具体的页面和后端传输的页面封装类，如
import java.io.Serializable;
import java.util.List;
public class XXXPage extends Page implements Serializable{
private String identity_type;
private String username;
private String name;
private String city;
private List<String> freeTimeList;
private String[] jobType;
private List<String> createdTimeList;
********************************
public String getIdentity_type() {
return identity_type;
}
public void setIdentity_type(String identity_type) {
this.identity_type = identity_type;
}
}
下一步可在controller的action中使用 如
public String listPageData(Model model, XXXPage page,HttpServletRequest request) {
xxxxxxxxx;
}
并在传回客户端时可 model.addAttribute("page", page);
其中 mybatis中操作
List<XXXBean> list = userMapper.findXXXByPage(page);//得到满足条件的招聘用户列表
int rows = xxxMapper.findRows(page);//得到满足条件的行数
page.setRows(rows);
只需要在mapper中sql中 进行sql分页 limit #{begin,jdbcType=INTEGER},#{showCount,jdbcType=INTEGER} 即可。
分页方法3：
修改mybatis自带的rowbound内存分页为物理分页
新建类Page_duan
import java.util.List;
import java.util.Map;
import org.codehaus.jackson.map.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.base.Joiner;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
public class Page_duan {
private static final long serialVersionUID = -399284318168302833L;
private static final Logger logger = LoggerFactory
.getLogger(Page_duan.class);
private static ObjectMapper mapper = new ObjectMapper();
public static String DEFAULT_PAGESIZE = "10";
private int pageNo; // 当前页码
private int pageSize; // 每页行数
private int totalRecord; // 总记录数
private int totalPage; // 总页数
private Map<String, String> params; // 查询条件
private Map<String, List<String>> paramLists; // 数组查询条件
private String searchUrl; // Url地址
private String pageNoDisp; // 可以显示的页号(分隔符"|"，总页数变更时更新)
private Page_duan() {
pageNo = 1;
pageSize = Integer.valueOf(DEFAULT_PAGESIZE);
totalRecord = 0;
totalPage = 0;
params = Maps.newHashMap();
paramLists = Maps.newHashMap();
searchUrl = "";
pageNoDisp = "";
}
public int getPageNo() {
return pageNo;
}
public void setPageNo(int pageNo) {
this.pageNo = pageNo;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
public int getTotalRecord() {
return totalRecord;
}
public void setTotalRecord(int totalRecord) {
this.totalRecord = totalRecord;
refreshPage();
}
public int getTotalPage() {
return totalPage;
}
public void setTotalPage(int totalPage) {
this.totalPage = totalPage;
}
public Map<String, String> getParams() {
return params;
}
public void setParams(Map<String, String> params) {
this.params = params;
}
public Map<String, List<String>> getParamLists() {
return paramLists;
}
public void setParamLists(Map<String, List<String>> paramLists) {
this.paramLists = paramLists;
}
public String getSearchUrl() {
return searchUrl;
}
public void setSearchUrl(String searchUrl) {
this.searchUrl = searchUrl;
}
public String getPageNoDisp() {
return pageNoDisp;
}
public void setPageNoDisp(String pageNoDisp) {
this.pageNoDisp = pageNoDisp;
}
public static Page_duan newBuilder(int pageNo, int pageSize, String url) {
Page_duan page = new Page_duan();
page.setPageNo(pageNo);
page.setPageSize(pageSize);
page.setSearchUrl(url);
return page;
}
/**
* 查询条件转JSON
*/
public String getParaJson() {
Map<String, Object> map = Maps.newHashMap();
for (String key : params.keySet()) {
if (params.get(key) != null) {
map.put(key, params.get(key));
}
}
String json = "";
try {
json = mapper.writeValueAsString(map);
} catch (Exception e) {
logger.error("转换JSON失败", params, e);
}
return json;
}
/**
* 数组查询条件转JSON
*/
public String getParaListJson() {
Map<String, Object> map = Maps.newHashMap();
for (String key : paramLists.keySet()) {
List<String> lists = paramLists.get(key);
if (lists != null && lists.size() > 0) {
map.put(key, lists);
}
}
String json = "";
try {
json = mapper.writeValueAsString(map);
} catch (Exception e) {
logger.error("转换JSON失败", params, e);
}
return json;
}
/**
* 总件数变化时，更新总页数并计算显示样式
*/
private void refreshPage() {
// 总页数计算
totalPage = totalRecord % pageSize == 0 ? totalRecord / pageSize
: (totalRecord / pageSize + 1);
// 防止超出最末页（浏览途中数据被删除的情况）
if (pageNo > totalPage && totalPage != 0) {
pageNo = totalPage;
}
pageNoDisp = computeDisplayStyleAndPage();
}
/**
* 计算页号显示样式 这里实现以下的分页样式("[]"代表当前页号)，可根据项目需求调整 [1],2,3,4,5,6,7,8..12,13
* 1,2..5,6,[7],8,9..12,13 1,2..6,7,8,9,10,11,12,[13]
*/
private String computeDisplayStyleAndPage() {
List<Integer> pageDisplays = Lists.newArrayList();
if (totalPage <= 11) {
for (int i = 1; i <= totalPage; i++) {
pageDisplays.add(i);
}
} else if (pageNo < 7) {
for (int i = 1; i <= 8; i++) {
pageDisplays.add(i);
}
pageDisplays.add(0);// 0 表示 省略部分(下同)
pageDisplays.add(totalPage - 1);
pageDisplays.add(totalPage);
} else if (pageNo > totalPage - 6) {
pageDisplays.add(1);
pageDisplays.add(2);
pageDisplays.add(0);
for (int i = totalPage - 7; i <= totalPage; i++) {
pageDisplays.add(i);
}
} else {
pageDisplays.add(1);
pageDisplays.add(2);
pageDisplays.add(0);
for (int i = pageNo - 2; i <= pageNo + 2; i++) {
pageDisplays.add(i);
}
pageDisplays.add(0);
pageDisplays.add(totalPage - 1);
pageDisplays.add(totalPage);
}
return Joiner.on("|").join(pageDisplays.toArray());
}
}
新建如下类
import java.util.Properties;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Invocation;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.Properties;
import org.apache.commons.jxpath.JXPathContext;
import org.apache.commons.jxpath.JXPathNotFoundException;
import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.executor.parameter.DefaultParameterHandler;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.MappedStatement.Builder;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.mapping.SqlSource;
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.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
@Intercepts({@Signature(type=Executor.class,method="query",
args={ MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class })})
public class PageHelper_duan implements Interceptor {
@Override
public Object intercept(Invocation invocation) throws Throwable {
//当前环境 MappedStatement，BoundSql，及sql取得
MappedStatement mappedStatement=(MappedStatement)invocation.getArgs()[0];
Object parameter = invocation.getArgs()[1];
BoundSql boundSql = mappedStatement.getBoundSql(parameter);
String originalSql = boundSql.getSql().trim();
Object parameterObject = boundSql.getParameterObject();
//Page对象获取，“信使”到达拦截器！
Page_duan page = searchPageWithXpath(boundSql.getParameterObject(),".","page","*/page");
if(page!=null ){
//Page对象存在的场合，开始分页处理
String countSql = getCountSql(originalSql);
Connection connection=mappedStatement.getConfiguration()
.getEnvironment().getDataSource().getConnection() ;
PreparedStatement countStmt = connection.prepareStatement(countSql);
BoundSql countBS = copyFromBoundSql(mappedStatement, boundSql, countSql);
DefaultParameterHandler parameterHandler = new DefaultParameterHandler(mappedStatement, parameterObject, countBS);
parameterHandler.setParameters(countStmt);
ResultSet rs = countStmt.executeQuery();
int totpage=0;
if (rs.next()) {
totpage = rs.getInt(1);
}
rs.close();
countStmt.close();
connection.close();
//分页计算
page.setTotalRecord(totpage);
//对原始Sql追加limit
int offset = (page.getPageNo() - 1) * page.getPageSize();
StringBuffer sb = new StringBuffer();
sb.append(originalSql).append(" limit ").append(offset).append(",").append(page.getPageSize());
BoundSql newBoundSql = copyFromBoundSql(mappedStatement, boundSql, sb.toString());
MappedStatement newMs = copyFromMappedStatement(mappedStatement,new BoundSqlSqlSource(newBoundSql));
invocation.getArgs()[0]= newMs;
}
return invocation.proceed();
}
/**
* 根据给定的xpath查询Page对象
*/
private Page_duan searchPageWithXpath(Object o,String... xpaths) {
JXPathContext context = JXPathContext.newContext(o);
Object result;
for(String xpath : xpaths){
try {
result = context.selectSingleNode(xpath);
} catch (JXPathNotFoundException e) {
continue;
}
if ( result instanceof Page_duan ){
return (Page_duan)result;
}
}
return null;
}
/**
* 复制MappedStatement对象
*/
private MappedStatement copyFromMappedStatement(MappedStatement ms,SqlSource newSqlSource) {
Builder builder = new Builder(ms.getConfiguration(),ms.getId(),newSqlSource,ms.getSqlCommandType());
builder.resource(ms.getResource());
builder.fetchSize(ms.getFetchSize());
builder.statementType(ms.getStatementType());
builder.keyGenerator(ms.getKeyGenerator());
for(String pro : ms.getKeyProperties())
builder.keyProperty(pro);
builder.timeout(ms.getTimeout());
builder.parameterMap(ms.getParameterMap());
builder.resultMaps(ms.getResultMaps());
builder.resultSetType(ms.getResultSetType());
builder.cache(ms.getCache());
builder.flushCacheRequired(ms.isFlushCacheRequired());
builder.useCache(ms.isUseCache());
return builder.build();
}
/**
* 复制BoundSql对象
*/
private BoundSql copyFromBoundSql(MappedStatement ms, BoundSql boundSql, String sql) {
BoundSql newBoundSql = new BoundSql(ms.getConfiguration(),sql, boundSql.getParameterMappings(), boundSql.getParameterObject());
for (ParameterMapping mapping : boundSql.getParameterMappings()) {
String prop = mapping.getProperty();
if (boundSql.hasAdditionalParameter(prop)) {
newBoundSql.setAdditionalParameter(prop, boundSql.getAdditionalParameter(prop));
}
}
return newBoundSql;
}
/**
* 根据原Sql语句获取对应的查询总记录数的Sql语句
*/
private String getCountSql(String sql) {
return "SELECT COUNT(*) FROM (" + sql + ") aliasForPage";
}
public class BoundSqlSqlSource implements SqlSource {
BoundSql boundSql;
public BoundSqlSqlSource(BoundSql boundSql) {
this.boundSql = boundSql;
}
public BoundSql getBoundSql(Object parameterObject) {
return boundSql;
}
}
@Override
public Object plugin(Object arg0) {
return Plugin.wrap(arg0, this);
}
@Override
public void setProperties(Properties arg0) {
// TODO Auto-generated method stub
}
}
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