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[Java微服务实战] Java 微服务实战，Spring Cloud Netflix套件、Spring Cloud Alibaba套件、Seata、gateway、shadingjdbc等实战操作
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[Spring] 讲解Spring(Bean)概念、IOC、AOP、集成jdbcTemplate/redis/事务等
前言
Apache ShardingSphere 是一款分布式的数据库生态系统， 可以将任意数据库转换为分布式数据库，并通过数据分片、弹性伸缩、加密等能力对原有数据库进行增强。
Apache ShardingSphere 设计哲学为 Database Plus，旨在构建异构数据库上层的标准和生态。 它关注如何充分合理地利用数据库的计算和存储能力，而并非实现一个全新的数据库。 它站在数据库的上层视角，关注它们之间的协作多于数据库自身。
1、ShardingSphere-JDBC
ShardingSphere-JDBC 定位为轻量级 Java 框架，在 Java 的 JDBC 层提供的额外服务。
1.1、应用场景
Apache ShardingSphere-JDBC 可以通过Java 和 YAML 这 2 种方式进行配置，开发者可根据场景选择适合的配置方式。
- 数据库读写分离
- 数据库分表分库
1.2、原理
- Sharding-JDBC中的路由结果是通过分片字段和分片方法来确定的,如果查询条件中有 id 字段的情况还好，查询将会落到某个具体的分片
- 如果查询没有分片的字段，会向所有的db或者是表都会查询一遍，让后封装结果集给客户端。
1.3、spring boot整合
1.3.1、添加依赖
<dependency> <groupId>org.apache.shardingspheregroupId> <artifactId>sharding-jdbc-spring-boot-starterartifactId> <version>4.1.1version>dependency>1.3.2、添加配置
spring: main: # 一个实体类对应多张表，覆盖 allow-bean-definition-overriding: true shardingsphere: datasource: ds0: #配置数据源具体内容，包含连接池，驱动，地址，用户名和密码 driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://127.0.0.1:3306/account?autoReconnect=true&allowMultiQueries=true password: root type: com.zaxxer.hikari.HikariDataSource username: root ds1: driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://127.0.0.1:3306/account?autoReconnect=true&allowMultiQueries=true password: root type: com.zaxxer.hikari.HikariDataSource username: root # 配置数据源，给数据源起名称 names: ds0,ds1 props: sql: show: true sharding: tables: user_info: #指定 user_info 表分布情况，配置表在哪个数据库里面，表名称都是什么 actual-data-nodes: ds0.user_info_${0..9} database-strategy: standard: preciseAlgorithmClassName: com.xxxx.store.account.config.PreciseDBShardingAlgorithm rangeAlgorithmClassName: com.xxxx.store.account.config.RangeDBShardingAlgorithm sharding-column: id table-strategy: standard: preciseAlgorithmClassName: com.xxxx.store.account.config.PreciseTablesShardingAlgorithm rangeAlgorithmClassName: com.xxxx.store.account.config.RangeTablesShardingAlgorithm sharding-column: id1.3.3、制定分片算法
1.3.3.1、精确分库算法
public class PreciseDBShardingAlgorithm implements PreciseShardingAlgorithm<Long> { @Override public String doSharding(Collection<String> availableTargetNames, PreciseShardingValue<Long> preciseShardingValue) { Long value = preciseShardingValue.getValue(); //后缀 0，1 String postfix = String.valueOf(value % 2); for (String availableTargetName : availableTargetNames) { if(availableTargetName.endsWith(postfix)){ return availableTargetName; } } throw new UnsupportedOperationException(); }}1.3.3.2、范围分库算法
public class RangeDBShardingAlgorithm implements RangeShardingAlgorithm<Long> { @Override public Collection<String> doSharding(Collection<String> collection, RangeShardingValue<Long> rangeShardingValue) { return collection; }}1.3.3.3、精确分表算法
public class PreciseTablesShardingAlgorithm implements PreciseShardingAlgorithm<Long> { @Override public String doSharding(Collection<String> availableTargetNames, PreciseShardingValue<Long> preciseShardingValue) { Long value = preciseShardingValue.getValue(); //后缀 String postfix = String.valueOf(value % 10); for (String availableTargetName : availableTargetNames) { if(availableTargetName.endsWith(postfix)){ return availableTargetName; } } throw new UnsupportedOperationException(); }}1.3.3.4、范围分表算法
public class RangeTablesShardingAlgorithm implements RangeShardingAlgorithm<Long> { @Override public Collection<String> doSharding(Collection<String> collection, RangeShardingValue<Long> rangeShardingValue) { Collection<String> result = new ArrayList<>(); Range<Long> valueRange = rangeShardingValue.getValueRange(); Long start = valueRange.lowerEndpoint(); Long end = valueRange.upperEndpoint(); Long min = start % 10; Long max = end % 10; for (Long i = min; i < max +1; i++) { Long finalI = i; collection.forEach(e -> { if(e.endsWith(String.valueOf(finalI))){ result.add(e); } }); } return result; }}1.3.4、数据库建表
DROP TABLE IF EXISTS `user_info_0`;CREATE TABLE `user_info_0` ( `id` bigint(20) NOT NULL, `account` varchar(255) DEFAULT NULL, `user_name` varchar(255) DEFAULT NULL, `pwd` varchar(255) DEFAULT NULL, PRIMARY KEY (`id`)) ENGINE=InnoDB DEFAULT CHARSET=utf8;1.3.5、业务应用
1.3.5.1、定义实体类
@Data@TableName(value = "user_info")public class UserInfo { private Long id; private String account; private String userName; private String pwd;}1.3.5.2、定义接口
public interface UserInfoService{ public UserInfo saveUserInfo(UserInfo userInfo); public UserInfo getUserInfoById(Long id); public List<UserInfo> listUserInfo();}1.3.5.3、实现类
@Servicepublic class UserInfoServiceImpl extends ServiceImpl<UserInfoMapper, UserInfo> implements UserInfoService { @Override @Transactional public UserInfo saveUserInfo(UserInfo userInfo) { userInfo.setId(IdUtils.getId()); this.save(userInfo); return userInfo; } @Override public UserInfo getUserInfoById(Long id) { return this.getById(id); } @Override public List<UserInfo> listUserInfo() { QueryWrapper<UserInfo> userInfoQueryWrapper = new QueryWrapper<>(); userInfoQueryWrapper.between("id",1623695688380448768L,1623695688380448769L); return this.list(userInfoQueryWrapper); }}1.3.6、生成ID - 雪花算法
package com.xxxx.tore.common.utils;import cn.hutool.core.lang.Snowflake;import cn.hutool.core.util.IdUtil;public class IdUtils { public static long getId(){ Snowflake snowflake = IdUtil.getSnowflake(0, 0); long id = snowflake.nextId(); return id; }} 1.4、seata与sharding-jdbc整合
https://github.com/seata/seata-samples/tree/master/springcloud-seata-sharding-jdbc-mybatis-plus-samples
1.4.1、common中添加依赖
<dependency> <groupId>com.alibaba.cloudgroupId> <artifactId>spring-cloud-starter-alibaba-seataartifactId> <version>2021.0.4.0version>dependency><dependency> <groupId>org.apache.shardingspheregroupId> <artifactId>sharding-transaction-base-seata-atartifactId> <version>4.1.1version>dependency><dependency> <groupId>com.alibaba.cloudgroupId> <artifactId>spring-cloud-starter-alibaba-nacos-discoveryartifactId> <version>2021.0.4.0version> <exclusions> <exclusion> <groupId>com.alibaba.nacosgroupId> <artifactId>nacos-clientartifactId> exclusion> exclusions>dependency><dependency> <groupId>com.alibaba.nacosgroupId> <artifactId>nacos-clientartifactId> <version>1.4.2version>dependency>1.4.2、改造account-service服务
@Servicepublic class AccountServiceImpl extends ServiceImpl<AccountMapper, Account> implements AccountService { @Autowired private OrderService orderService; @Autowired private StorageService storageService; private static Map<String,Integer> map = new HashMap<>(); static { map.put("c001",3); map.put("c002",5); map.put("c003",10); map.put("c004",6); } @Override @Transactional @ShardingTransactionType(TransactionType.BASE) public void debit(OrderDTO orderDTO) { //扣减账户余额 int calculate = this.calculate(orderDTO.getCommodityCode(), orderDTO.getCount()); AccountDTO accountDTO = new AccountDTO(orderDTO.getUserId(), calculate); QueryWrapper<Account> objectQueryWrapper = new QueryWrapper<>(); objectQueryWrapper.eq("id",1); objectQueryWrapper.eq(accountDTO.getUserId() != null,"user_id",accountDTO.getUserId()); Account account = this.getOne(objectQueryWrapper); account.setMoney(account.getMoney() - accountDTO.getMoney()); this.saveOrUpdate(account); //扣减库存 this.storageService.deduct(new StorageDTO(null,orderDTO.getCommodityCode(),orderDTO.getCount())); //生成订单 this.orderService.create(orderDTO); } private int calculate(String commodityCode, int orderCount){ //商品价钱 Integer price = map.get(commodityCode) == null ? 0 : map.get(commodityCode); return price * orderCount; }}注意：调单生成调用的逻辑修改，减余额->减库存->生成订单。调用入口方法注解加上：@ShardingTransactionType(TransactionType.BASE)
1.4.3、修改business-service服务
@Servicepublic class BusinessServiceImpl implements BusinessService { @Autowired private OrderService orderService; @Autowired private StorageService storageService; @Autowired private AccountService accountService; @Override public void purchase(OrderDTO orderDTO) { //扣减账号中的钱 accountService.debit(orderDTO); }}1.4.4、修改order-service服务
@Servicepublic class OrderServiceImpl extends ServiceImpl<OrderMapper,Order> implements OrderService { private static Map<String,Integer> map = new HashMap<>(); static { map.put("c001",3); map.put("c002",5); map.put("c003",10); map.put("c004",6); } @Override @Transactional @ShardingTransactionType(TransactionType.BASE) public Order create(String userId, String commodityCode, int orderCount) { int orderMoney = calculate(commodityCode, orderCount); Order order = new Order(); order.setUserId(userId); order.setCommodityCode(commodityCode); order.setCount(orderCount); order.setMoney(orderMoney); //保存订单 this.save(order); try { TimeUnit.SECONDS.sleep(30); } catch (InterruptedException e) { e.printStackTrace(); } if(true){ throw new RuntimeException("回滚测试"); } return order; } private int calculate(String commodityCode, int orderCount){ //商品价钱 Integer price = map.get(commodityCode) == null ? 0 : map.get(commodityCode); return price * orderCount; }}1.4.5、配置文件参考
server: port: 8090spring: main: # 一个实体类对应多张表，覆盖 allow-bean-definition-overriding: true shardingsphere: datasource: ds0: #配置数据源具体内容，包含连接池，驱动，地址，用户名和密码 driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://127.0.0.1:3306/account?autoReconnect=true&allowMultiQueries=true password: root type: com.zaxxer.hikari.HikariDataSource username: root ds1: driver-class-name: com.mysql.cj.jdbc.Driver jdbc-url: jdbc:mysql://127.0.0.1:3306/account?autoReconnect=true&allowMultiQueries=true password: root type: com.zaxxer.hikari.HikariDataSource username: root # 配置数据源，给数据源起名称 names: ds0,ds1 props: sql: show: true sharding: tables: account_tbl: actual-data-nodes: ds0.account_tbl_${0..1} database-strategy: standard: preciseAlgorithmClassName: com.xxxx.store.account.config.PreciseDBExtShardingAlgorithm #rangeAlgorithmClassName: com.xxxx.store.account.config.RangeDBShardingAlgorithm sharding-column: id table-strategy: standard: preciseAlgorithmClassName: com.xxxx.store.account.config.PreciseTablesExtShardingAlgorithm #rangeAlgorithmClassName: com.xxxx.store.account.config.RangeTablesShardingAlgorithm sharding-column: id user_info: #指定 user_info 表分布情况，配置表在哪个数据库里面，表名称都是什么 actual-data-nodes: ds0.user_info_${0..9} database-strategy: standard: preciseAlgorithmClassName: com.xxxx.store.account.config.PreciseDBShardingAlgorithm rangeAlgorithmClassName: com.xxxx.store.account.config.RangeDBShardingAlgorithm sharding-column: id table-strategy: standard: preciseAlgorithmClassName: com.xxxx.store.account.config.PreciseTablesShardingAlgorithm rangeAlgorithmClassName: com.xxxx.store.account.config.RangeTablesShardingAlgorithm sharding-column: id #以上是sharding-jdbc配置 cloud: nacos: discovery: server-addr: localhost:8848 namespace: 1ff3782d-b62d-402f-8bc4-ebcf40254d0a application: name: account-service #微服务名称# datasource:# username: root# password: root# url: jdbc:mysql://127.0.0.1:3306/account# driver-class-name: com.mysql.cj.jdbc.Driverseata: enabled: true enable-auto-data-source-proxy: false application-id: account-service tx-service-group: default_tx_group service: vgroup-mapping: default_tx_group: default disable-global-transaction: false registry: type: nacos nacos: application: seata-server server-addr: 127.0.0.1:8848 namespace: 1ff3782d-b62d-402f-8bc4-ebcf40254d0a group: SEATA_GROUP username: nacos password: nacos config: nacos: server-addr: 127.0.0.1:8848 namespace: 1ff3782d-b62d-402f-8bc4-ebcf40254d0a group: SEATA_GROUP username: nacos password: nacos联系方式
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系列文章目录
第一章 Java线程池技术应用
第二章 CountDownLatch和Semaphone的应用
第三章 Spring Cloud 简介
第四章 Spring Cloud Netflix 之 Eureka
第五章 Spring Cloud Netflix 之 Ribbon
第六章 Spring Cloud 之 OpenFeign
第七章 Spring Cloud 之 GateWay
第八章 Spring Cloud Netflix 之 Hystrix
第九章 代码管理gitlab 使用
第十章 SpringCloud Alibaba 之 Nacos discovery
第十一章 SpringCloud Alibaba 之 Nacos Config
第十二章 Spring Cloud Alibaba 之 Sentinel
第十三章 JWT
第十四章 RabbitMQ应用
第十五章 RabbitMQ 延迟队列
第十六章 spring-cloud-stream
第十七章 Windows系统安装Redis、配置环境变量
第十八章 查看、修改Redis配置，介绍Redis类型
第十九章 ShardingSphere - ShardingSphere-JDBC
来源地址：https://blog.csdn.net/s445320/article/details/135506181
