Interceptor接口
package org.apache.ibatis.plugin; import java.util.Properties; /** * @author Clinton Begin */ public interface Interceptor { Object intercept(Invocation invocation) throws Throwable; Object plugin(Object target); void setProperties(Properties properties); } **pom.xml :** <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> create table user ( id int auto_increment primary key, username varchar(20) null ); public class PageVo { protected int page = 1;//当前页数，默认为1 protected int rows = 15;//每页显示条数,默认为15 private int offset = 0;//每页起始条数 private int limit = 15;//每页结束条数 public int getLimit() { return (page - 1) * rows; } public void setLimit(int limit) { this.limit = limit; } public int getOffset() { return page * rows; } public void setOffset(int offset) { this.offset = (page - 1) * rows; } public int getPage() { return page; } public void setPage(int page) { this.page = page; } public int getRows() { return rows; } public void setRows(int rows) { this.rows = rows; } } package com.wtn.mybatis_plugs.util; import java.util.List; public class PageResult<T> { private int pageNo = 1;// 页码，默认是第一页 private int pageSize = 3;// 每页显示的记录数，默认是15 private int total;// 总记录数 private int totalPage;// 总页数 private List<T> rows; private int offset = 0;// 偏移量，当前页起始记录数 private int limit = 15; private boolean count = true; public PageResult() { } public PageResult(int pageNo, int pageSize, int total, List<T> rows) { this.pageNo = pageNo; this.pageSize = pageSize; this.total = total; this.setRows(rows); int totalPage = total % pageSize == 0 ? total / pageSize : total / pageSize + 1; this.setTotalPage(totalPage); } public List<T> getRows() { return rows; } public void setRows(List<T> rows) { this.rows = rows; } public int getOffset() { return offset; } public void setOffset(int offset) { // this.offset = offset; this.offset = (this.pageNo - 1) * pageSize; } public int getLimit() { return limit; } public void setLimit(int limit) { this.limit = limit; } public boolean isCount() { return count; } public void setCount(boolean count) { this.count = count; } @Override public String toString() { return "Page [pageNo=" + pageNo + ", pageSize=" + pageSize + ", totalRecord=" + total + ", totalPage=" + totalPage + ", rows=" + rows + ", offset=" + offset + ", limit=" + limit + ", count=" + count + "]"; } 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 getTotal() { return total; } public void setTotal(int total) { this.total = total; int totalPage = total % pageSize == 0 ? total / pageSize : total / pageSize + 1; this.setTotalPage(totalPage); } public int getTotalPage() { return totalPage; } public void setTotalPage(int totalPage) { this.totalPage = totalPage; } }拦截器部分 主要思路是判断是否继承我们的PageVo这个类，如果继承了就进行分页处理，我这里分页重新拼接sql执行
@Override public Object intercept(Invocation invocation) throws Throwable { logger.info("进入拦截器"); Object[] args = invocation.getArgs(); MappedStatement mappedStatement = (MappedStatement) args[0]; //获取参数 Object param = invocation.getArgs()[1]; BoundSql boundSql = mappedStatement.getBoundSql(param); Object parameterObject = boundSql.getParameterObject(); /** * 判断是否是继承PageVo来判断是否需要进行分页 */ if (parameterObject instanceof PageVo) { //强转 为了拿到分页数据 PageVo pagevo = (PageVo) param; String sql = boundSql.getSql(); //获取相关配置 Configuration config = mappedStatement.getConfiguration(); Connection connection = config.getEnvironment().getDataSource().getConnection(); //拼接查询当前条件的sql的总条数 String countSql = "select count(*) from (" + sql + ") a"; PreparedStatement preparedStatement = connection.prepareStatement(countSql); BoundSql countBoundSql = new BoundSql(config, countSql, boundSql.getParameterMappings(), boundSql.getParameterObject()); ParameterHandler parameterHandler = new DefaultParameterHandler(mappedStatement, parameterObject, countBoundSql); parameterHandler.setParameters(preparedStatement); //执行获得总条数 ResultSet rs = preparedStatement.executeQuery(); int count = 0; if (rs.next()) { count = rs.getInt(1); } //拼接分页sql String pageSql = sql + " limit " + pagevo.getLimit() + " , " + pagevo.getOffset(); //重新执行新的sql doNewSql(invocation, pageSql); Object result = invocation.proceed(); connection.close(); //处理新的结构 PageResult<?> pageResult = new PageResult<List>(pagevo.page, pagevo.rows, count, (List) result); List<PageResult> returnResultList = new ArrayList<>(); returnResultList.add(pageResult); return returnResultList; } return invocation.proceed(); } @PostMapping("/findUserPage") public List<User> findUserPage(@RequestBody UserDto userDto){ return userService.findUserPage(userDto); } https://github.com/XINYANJIANG/mybaits-plugs