package com.from.mybatis.handler;

​

import cn.hutool.core.date.DateUtil;

import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;

import org.apache.ibatis.reflection.MetaObject;

import org.springframework.stereotype.Component;

​

import java.util.Date;

​

@Component

public class MyBatisMetaObjectHandler implements MetaObjectHandler {

    /**

     * 自定义插入时填充规则

     */

    @Override

    public void insertFill(MetaObject metaObject) {

        // 注意是类属性字段名称，不是表字段名称

        this.setFieldValByName("createTime", new Date(), metaObject);

        this.setFieldValByName("delFlag", 0, metaObject);

    }

​

    /**

     * 自定义更新时填充规则

     */

    @Override

    public void updateFill(MetaObject metaObject) {

        String now = DateUtil.now();

        // 注意是类属性字段名称，不是表字段名称

        this.setFieldValByName("updateTime", new Date(), metaObject);

    }

​

}

​

id生成器代码:

package com.from.mybatis.config;

​

import java.util.Date;

import java.util.UUID;

​

/**

 * compressed id generator, result id not great than 53bits before 2318-06-04.

 */

public class IdGenerator {

​

    private static IdGenerator instance = new IdGenerator(0);

​

    public static IdGenerator initDefaultInstance(int machineId) {

        instance = new IdGenerator(machineId);

        return instance;

    }

​

    public static IdGenerator getInstance() {

        return instance;

    }

​

    public static long generateId() {

        return instance.nextId();

    }

​

    // total bits=53(max 2^53-1：9007199254740992-1)

​

    // private final static long TIME_BIT = 40; // max: 2318-06-04

    private final static long MACHINE_BIT = 5; // max 31

    private final static long SEQUENCE_BIT = 8; // 256/10ms

​

    /**

     * mask/max value

     */

    private final static long MAX_MACHINE_NUM = -1L ^ (-1L << MACHINE_BIT);

    private final static long MAX_SEQUENCE = -1L ^ (-1L << SEQUENCE_BIT);

​

    private final static long MACHINE_LEFT = SEQUENCE_BIT;

    private final static long TIMESTMP_LEFT = MACHINE_BIT + SEQUENCE_BIT;

​

    private long machineId;

    private long sequence = 0L;

    private long lastStmp = -1L;

​

    private IdGenerator(long machineId) {

        if (machineId > MAX_MACHINE_NUM || machineId < 0) {

            throw new IllegalArgumentException(

                    "machineId can't be greater than " + MAX_MACHINE_NUM + " or less than 0");

        }

        this.machineId = machineId;

    }

​

    /**

     * generate new ID

     *

     * @return

     */

    public synchronized long nextId() {

        long currStmp = getTimestamp();

        if (currStmp < lastStmp) {

            throw new RuntimeException("Clock moved backwards.  Refusing to generate id");

        }

​

        if (currStmp == lastStmp) {

            sequence = (sequence + 1) & MAX_SEQUENCE;

            if (sequence == 0L) {

                currStmp = getNextTimestamp();

            }

        } else {

            sequence = 0L;

        }

​

        lastStmp = currStmp;

​

        return currStmp << TIMESTMP_LEFT //

                | machineId << MACHINE_LEFT //

                | sequence;

    }

​

    private long getNextTimestamp() {

        long mill = getTimestamp();

        while (mill <= lastStmp) {

            mill = getTimestamp();

        }

        return mill;

    }

​

    private long getTimestamp() {

        // per 10ms

        return System.currentTimeMillis() / 10;// 10ms

    }

​

    public static Date parseIdTimestamp(long id) {

        return new Date((id >>> TIMESTMP_LEFT) * 10);

    }

​

    public static String uuid() {

        return UUID.randomUUID().toString().replaceAll("-", "");

    }

}

package com.from.mybatis.config;

​

​

import com.baomidou.mybatisplus.core.incrementer.IdentifierGenerator;

import org.springframework.stereotype.Component;

​

@Component

public class CustomerIdGenerator implements IdentifierGenerator {

    @Override

    public Long nextId(Object entity) {

        // 填充自己的Id生成器，

        return IdGenerator.generateId();

    }

}

package com.from.seata.config;

import com.alibaba.druid.pool.DruidDataSource;

import com.baomidou.mybatisplus.annotation.DbType;

import com.baomidou.mybatisplus.autoconfigure.MybatisPlusProperties;

import com.baomidou.mybatisplus.core.MybatisConfiguration;

import com.baomidou.mybatisplus.core.config.GlobalConfig;

import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;

import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;

import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;

import com.from.mybatis.config.CustomerIdGenerator;

import com.from.mybatis.handler.MyBatisMetaObjectHandler;

import io.seata.rm.datasource.DataSourceProxy;

import org.mybatis.spring.transaction.SpringManagedTransactionFactory;

import org.springframework.boot.context.properties.ConfigurationProperties;

import org.springframework.boot.context.properties.EnableConfigurationProperties;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import org.springframework.context.annotation.Primary;

import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

import java.io.IOException;

@Configuration

@EnableConfigurationProperties({MybatisPlusProperties.class})

public class DataSourcesProxyConfig {

    //自动填充注入

    @Bean

    public MyBatisMetaObjectHandler myBatisMetaObjectHandler() {

        return new MyBatisMetaObjectHandler();

    }

    //id生成器注入

    @Bean

    public CustomerIdGenerator customerIdGenerator() {

        return new CustomerIdGenerator();

    }

    //获取数据源

    @Bean

    @ConfigurationProperties(prefix = "spring.datasource")

    public DataSource druidDataSource() {

        return new DruidDataSource();

    }

​

    //配种数据源

    @Primary//@Primary标识必须配置在代码数据源上，否则本地事务失效

    @Bean

    public DataSourceProxy dataSourceProxy(DataSource druidDataSource) {

        return new DataSourceProxy(druidDataSource);

    }

​

    private MybatisPlusProperties properties;

​

    public DataSourcesProxyConfig(MybatisPlusProperties properties) {

        this.properties = properties;

    }

​

    //配置mybatisplus的数据源,所有插件会失效,所以注入进来,配置给代理数据源

    @Bean

    public MybatisSqlSessionFactoryBean sqlSessionFactory(DataSourceProxy dataSourceProxy) throws Exception {

        // 这里必须用 MybatisSqlSessionFactoryBean 代替了 SqlSessionFactoryBean，否则 MyBatisPlus 不会生效

        MybatisSqlSessionFactoryBean sqlBean = new MybatisSqlSessionFactoryBean();

        sqlBean.setDataSource(dataSourceProxy);

        sqlBean.setTransactionFactory(new SpringManagedTransactionFactory());

        try {

            //注意:!!!!这个如果写的有sql,须有该配置,try cach以下,打开不捕获异常的化,没sql会报错

            sqlBean.setMapperLocations(new PathMatchingResourcePatternResolver()

                    .getResources("classpath:/mapper/**/*.xml"));

        } catch (IOException ignored) {

        }

        MybatisConfiguration configuration = this.properties.getConfiguration();

        if (configuration == null) {

            configuration = new MybatisConfiguration();

        }

        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();

        //向代理数据源添加分页拦截器

        interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));

        sqlBean.setPlugins(interceptor);

        //代理数据源添加id生成器,字段自动填充

        sqlBean.setGlobalConfig(new GlobalConfig()

                .setMetaObjectHandler(myBatisMetaObjectHandler())

                .setIdentifierGenerator(customerIdGenerator()));

        sqlBean.setConfiguration(configuration);

        return sqlBean;

    }

}