基于Mybatis拦截器开发自定义拦截器，实现记录数据表最后更新时间

「爱情、让人受尽委屈。」 2024-04-01 17:40 44阅读 0赞

**场景：**  
记录有过增删改操作的数据表及最后更新时间，实现数据增量同步。

**解决方案：**基于Mybatis拦截器开发自定义拦截器

1.实现Mybatis拦截器Interceptor，重写intercept方法

2.使用druid解析sql，获取sql中涉及的表

3.实现自定义逻辑

**拦截器代码如下：**

package com.cms.filter;
    
    import com.alibaba.druid.sql.SQLUtils;
    import com.alibaba.druid.sql.ast.SQLStatement;
    import com.alibaba.druid.sql.dialect.mysql.visitor.MySqlSchemaStatVisitor;
    import com.alibaba.druid.stat.TableStat;
    import com.alibaba.druid.util.JdbcConstants;
    import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
    import com.baomidou.mybatisplus.core.toolkit.CollectionUtils;
    import com.cms.common.utils.StringUtils;
    import com.cms.common.utils.spring.SpringUtils;
    import com.cms.domain.entity.systemData.SystemData;
    import com.cms.mapper.systemData.SystemDataMapper;
    import lombok.extern.slf4j.Slf4j;
    import org.apache.ibatis.executor.Executor;
    import org.apache.ibatis.mapping.BoundSql;
    import org.apache.ibatis.mapping.MappedStatement;
    import org.apache.ibatis.mapping.SqlCommandType;
    import org.apache.ibatis.plugin.*;
    import org.springframework.stereotype.Component;
    
    import java.util.*;
    import java.util.stream.Collectors;
    
    /**
     * @author daixin
     * @version 1.0
     * @description: TODO
     * @date 2022/9/28 13:48
     */
    @Slf4j
    @Component
    @Intercepts({@Signature(type = Executor.class, method = "update", args = {MappedStatement.class, Object.class})})
    public class ExecutorDataVaryInterceptor implements Interceptor {
    
        /**
         * 拦截方法逻辑
         */
        @Override
        public Object intercept(Invocation invocation) throws Throwable {
            //方法参数
            Object[] args = invocation.getArgs();
            MappedStatement mappedStatement = (MappedStatement) args[0];
            Object parameterObject = args[1];
    
            //获取Sql命令类型UNKNOWN, INSERT, UPDATE, DELETE, SELECT, FLUSH
            SqlCommandType sqlCommandType = mappedStatement.getSqlCommandType();
            String commandType = sqlCommandType.name();
            //获取拦截的Sql
            BoundSql boundSql = mappedStatement.getSqlSource().getBoundSql(parameterObject);
            String sql = boundSql.getSql();
            //判断新增和修改操作，执行自定义逻辑
            if("INSERT".equalsIgnoreCase(commandType)||"UPDATE".equalsIgnoreCase(commandType)){
                //解析Sql, 获取涉及的数据表
                List<String> tableNameList =  getTableNameBySql(sql);
                //判断sql执行的数据表是否在需要管理的白名单内
                QueryWrapper<SystemData> queryWrapper = new QueryWrapper<>();
                queryWrapper.lambda().in(SystemData::getTableName,tableNameList);
                SystemDataMapper systemDataMapper = SpringUtils.getBean(SystemDataMapper.class);
                List<SystemData> systemDataList = systemDataMapper.selectList(queryWrapper);
                //在白名单内的表, 管理更新时间
                if(!StringUtils.isEmpty(systemDataList)){
                    List<String> updateTimeTables = systemDataList.stream().map(SystemData::getTableName).collect(Collectors.toList());
                    systemDataMapper.saveUpdateTimeBatch(updateTimeTables);
                }
            }
            Object result = invocation.proceed();
            return result;
        }
    
        /**
         * 解析Sql，获取涉及的数据表
         * @param sql
         * @return
         */
        private List<String> getTableNameBySql(String sql) {
            try {
                String dbType = String.valueOf(JdbcConstants.MYSQL);
                List<String> tableNameList = new ArrayList<>();
                log.info("格式化后的sql:{}",SQLUtils.format(sql, dbType));
    
                List<SQLStatement> sqlStatementList = SQLUtils.parseStatements(sql, dbType);
                if (CollectionUtils.isEmpty(sqlStatementList)) {
                    return Collections.emptyList();
                }
                for (SQLStatement sqlStatement : sqlStatementList) {
                    MySqlSchemaStatVisitor visitor = new MySqlSchemaStatVisitor();
                    sqlStatement.accept(visitor);
                    Map<TableStat.Name, TableStat> tables = visitor.getTables();
                    for (TableStat.Name name : tables.keySet()) {
                        String tableName = name.getName();
                        if (StringUtils.isNotBlank(tableName)) {
                            tableNameList.add(tableName);
                        }
                    }
                }
                log.info("解析sql获取的表名:{}",tableNameList);
                return tableNameList;
            } catch (Exception e) {
                log.error("===================异常SQL=================={}",sql);
                log.error(e.getMessage(),e);
            }
            return Collections.emptyList();
        }
    
    }

**mybatis-config.xml注入拦截器**

**spring boot集成druid所需依赖**

<dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
        <version>${druid.version}</version>
    </dependency>
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.2.8</version>
        <scope>compile</scope>
    </dependency>

同理，也可实现日志收集等功能。