Java简单实现SpringMVC+MyBatis分页插件

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 threadLocal = new ThreadLocal();

  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();
  }
  

   
  private void setParameters(PreparedStatement ps,MappedStatement mappedStatement,BoundSql boundSql,Object parameterObject) throws SQLException { 
    ErrorContext.instance().activity("setting parameters").object(mappedStatement.getParameterMap().getId()); 
    List 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()); 
 } 
      } 
    } 
  } 
  
   
  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

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;

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

  
  
  
    
      classpath:/com/framework/mapper*Mapper.xml
    
  




  
  
  

6.SpringMVC配置拦截器