先丢代码地址
https://gitee.com/a247292980/sharding-jdbc
再丢pom.xml的dependency
<properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <spring.version>3.2.5.RELEASE</spring.version> <mybatis.version>3.2.4</mybatis.version> </properties> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.10</version> </dependency> <dependency> <groupId>com.dangdang</groupId> <artifactId>sharding-jdbc-core</artifactId> <version>1.0.0</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>commons-dbcp</groupId> <artifactId>commons-dbcp</artifactId> <version>1.4</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.2.2</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${mybatis.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-expression</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.28</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.16</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>1.7.5</version> </dependency> </dependencies>
最后丢代码结构图
我讲shardingJdbc.java这个文件的东西，留意好我的注释
public class ShardingJdbc {
/**
* main方法
*/
public static void main(String[] args) {
// 设置数据源，不分库的话，只设置一个
Map<String, DataSource> dataSourceMap = new HashMap<String, DataSource>(2);
dataSourceMap.put("sharding_0", createDataSource("sharding_0"));
dataSourceMap.put("sharding_1", createDataSource("sharding_1"));
DataSourceRule dataSourceRule = new DataSourceRule(dataSourceMap);
//分表分库的表，第一个参数是逻辑表名，第二个是实际表名，第三个是实际库
TableRule orderTableRule = new TableRule("t_order", Arrays.asList("t_order_0", "t_order_1"), dataSourceRule);
TableRule orderItemTableRule = new TableRule("t_order_item", Arrays.asList("t_order_item_0", "t_order_item_1"), dataSourceRule);
/**
* DatabaseShardingStrategy 分库策略
* 参数一：根据哪个字段分库
* 参数二：分库路由函数
*
* TableShardingStrategy 分表策略
* 参数一：根据哪个字段分表
* 参数二：分表路由函数
*
* user_id选择哪个库
* order_id选择那个表
*
* ModuloDataBaseShardingAlgorithm
* ModuloTableShardingAlgorithm
* 被2整除是0，反之是1
*
*/
ShardingRule shardingRule = new ShardingRule(dataSourceRule, Arrays.asList(orderTableRule, orderItemTableRule)
, Arrays.asList(new BindingTableRule(Arrays.asList(orderTableRule, orderItemTableRule)))
, new DatabaseShardingStrategy("user_id", new ModuloDataBaseShardingAlgorithm())
, new TableShardingStrategy("order_id", new ModuloTableShardingAlgorithm()));
DataSource dataSource = new ShardingDataSource(shardingRule);
String sql =
"SELECT i.* FROM t_order o JOIN t_order_item i " +
"ON o.order_id=i.order_id " +
"WHERE o.user_id= ? AND o.order_id = ?";
try {
Connection connection = dataSource.getConnection();
PreparedStatement preparedStatement = connection.prepareStatement(sql);
// preparedStatement.setInt(1, 10);
// preparedStatement.setInt(2, 1001);
// 先根据分库规则去了sharding_1
preparedStatement.setInt(1, 11);
// 再根据分表规则去了t_order_0,t_order_item_0
preparedStatement.setInt(2, 1000);
ResultSet result = preparedStatement.executeQuery();
while (result.next()) {
System.out.println("1--------" + result.getInt(1));
System.out.println("2--------" + result.getInt(2));
System.out.println("3--------" + result.getInt(3));
}
} catch (SQLException e) {
e.printStackTrace();
}
}
/**
* @param dataSourceName
* @return dataSource
* @DESCRIPTION 创建数据源
*/
private static DataSource createDataSource(String dataSourceName) {
BasicDataSource dataSource = new BasicDataSource();
dataSource.setDriverClassName("com.mysql.jdbc.Driver");
dataSource.setUrl(String.format("jdbc:mysql://localhost:3306/%s", dataSourceName));
dataSource.setUsername("root");
dataSource.setPassword("123456789");
return dataSource;
}
}
另两个放的是具体分库逻辑，很简单，有兴趣的下源码跑一下即可