資料庫建立

create database demo_ds_master; //建立主庫

create database demo_ds_slave_0; //建立從庫1

create database demo_ds_slave_1; //建立從庫2

匯入依賴

<dependencies>

<dependency>

<groupId>junit</groupId>

<artifactId>junit</artifactId>

<version>4.0</version>

<scope>test</scope>

</dependency>

<dependency>

<groupId>io.shardingjdbc</groupId>

<artifactId>sharding-jdbc-core</artifactId>

<version>2.0.0.M2</version>

</dependency>

<dependency>

<groupId>io.shardingjdbc</groupId>

<artifactId>sharding-jdbc-spring-namespace

<version>2.0.0.M2</version>

</dependency>

<dependency>

<groupId>com.alibaba</groupId>

<artifactId>druid</artifactId>

<version>1.0.13</version>

</dependency>

<dependency>

<groupId>mysql</groupId>

<artifactId>mysql

<version>5.1.28</version>

</dependency>

<dependency>

<groupId>org.slf4j</groupId>

<artifactId>slf4j-api</artifactId>

<version>1.7.7</version>

</dependency>

<dependency>

<groupId>ch.qos.logback</groupId>

<artifactId>logback-classic</artifactId>

<version>1.0.13</version>

</dependency>

</dependencies>

程式碼:

1.建立資料來源的工具類:package com.irisian.sharedjdbc.masterandslave;

import javax.sql.DataSource;

import com.alibaba.druid.pool.DruidDataSource;

public class DataSourceUtil {

    private static final String URL_PREFIX = "jdbc:mysql://localhost:3306/";

    private static final String USER_NAME = "root";

    private static final String PASSWORD = "123456";

    public static DataSource createDataSource(final String dataSourceName) {

DruidDataSource result = new DruidDataSource();

        result.setDriverClassName(com.mysql.jdbc.Driver.class.getName());

        result.setUrl(URL_PREFIX + dataSourceName);

        result.setUsername(USER_NAME);

        result.setPassword(PASSWORD);

        return result;

    }

}

2.主從資料庫配置

package com.irisian.sharedjdbc.masterandslave;

import java.sql.SQLException;

import java.util.Arrays;

import java.util.HashMap;

import java.util.Map;

import javax.sql.DataSource;

import io.shardingjdbc.core.api.MasterSlaveDataSourceFactory;

import io.shardingjdbc.core.api.config.MasterSlaveRuleConfiguration;

public final class RawJdbcJavaMasterSlaveOnlyMain {

public static void main(String[] args) throws SQLException {

new RawJdbcRepository(getMasterSlaveDataSource()).demo();

}

public static DataSource getMasterSlaveDataSource() throws SQLException {

MasterSlaveRuleConfiguration masterSlaveRule = new MasterSlaveRuleConfiguration();

masterSlaveRule.setName("demo_ds_master_slave");//主從規則的名稱，此名稱隨意起

masterSlaveRule.setMasterDataSourceName("demo_ds_master");//主資料來源名稱，和createDataSourceMap物件

masterSlaveRule.setSlaveDataSourceNames(Arrays.asList("demo_ds_slave_0", "demo_ds_slave_1"));//從資料來源名稱，和createDataSourceMap物件

masterSlaveRule.setLoadBalanceAlgorithmClassName(

"io.shardingjdbc.core.api.algorithm.masterslave.RandomMasterSlaveLoadBalanceAlgorithm");//負載平衡的策略

return MasterSlaveDataSourceFactory.createDataSource(createDataSourceMap(), masterSlaveRule);

}

private static Map<String, DataSource> createDataSourceMap() {

final Map<String, DataSource> result = new HashMap<>(3, 1);

result.put("demo_ds_master", DataSourceUtil.createDataSource("demo_ds_master"));//建立主庫的資料來源連線

result.put("demo_ds_slave_0", DataSourceUtil.createDataSource("demo_ds_slave_0"));//建立從庫的資料來源連線

result.put("demo_ds_slave_1", DataSourceUtil.createDataSource("demo_ds_slave_1"));//建立從庫的資料來源連線

return result;

}

}

3.測試的類

package com.irisian.sharedjdbc.masterandslave;

import io.shardingjdbc.core.api.HintManager;

import javax.sql.DataSource;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

public class RawJdbcRepository {

private final DataSource dataSource;

public RawJdbcRepository(final DataSource dataSource) {

this.dataSource = dataSource;

}

public void demo() throws SQLException {

// createTable();      //建立表的語句

// insertData();//插入僅僅會插入到主資料來源裡面，然後配置mysql主從同步(需要自己配置，shareding-jdbc無法自動完成),配置了之後就可以從從庫中讀取了

//for (int i = 0; i < 30; i++) {//查詢均從從庫中讀取，如果從庫集中有一個數據庫中沒有資料，剛好從此資料庫中讀取資料，則讀取不到任何的資料

//System.out.println("1.Equals Select--------------");

//printEqualsSelect();

//}

System.out.println("1.Equals Select--------------");

printEqualsSelect();

// System.out.println("2.In Select--------------");

// printInSelect();

// System.out.println("3.Hint Select--------------");

// printHintSimpleSelect();

// dropTable();

}

public void createTable() throws SQLException {

execute(dataSource,

"CREATE TABLE IF NOT EXISTS t_order (order_id BIGINT NOT NULL AUTO_INCREMENT, user_id INT NOT NULL, status VARCHAR(50), PRIMARY KEY (order_id))");

execute(dataSource,

"CREATE TABLE IF NOT EXISTS t_order_item (order_item_id BIGINT NOT NULL AUTO_INCREMENT, order_id BIGINT NOT NULL, user_id INT NOT NULL, PRIMARY KEY (order_item_id))");

}

public void dropTable() throws SQLException {

execute(dataSource, "DROP TABLE t_order_item");

execute(dataSource, "DROP TABLE t_order");

}

public void insertData() throws SQLException {

for (int i = 1; i < 10; i++) {

long orderId = executeAndGetGeneratedKey(dataSource,

"INSERT INTO t_order (user_id, status) VALUES (10, 'INIT')");

execute(dataSource, String.format("INSERT INTO t_order_item (order_id, user_id) VALUES (%d, 10)", orderId));

orderId = executeAndGetGeneratedKey(dataSource,

"INSERT INTO t_order (user_id, status) VALUES (11, 'INIT')");

execute(dataSource, String.format("INSERT INTO t_order_item (order_id, user_id) VALUES (%d, 11)", orderId));

}

}

public void printEqualsSelect() throws SQLException {

String sql = "SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o.user_id=?";

try (Connection conn = dataSource.getConnection();

PreparedStatement preparedStatement = conn.prepareStatement(sql)) {

preparedStatement.setInt(1, 10);

printSimpleSelect(preparedStatement);

}

}

public void printInSelect() throws SQLException {

String sql = "SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id WHERE o.user_id IN (?, ?)";

try (Connection conn = dataSource.getConnection();

PreparedStatement preparedStatement = conn.prepareStatement(sql)) {

preparedStatement.setInt(1, 10);

preparedStatement.setInt(2, 11);

printSimpleSelect(preparedStatement);

}

}

public void printHintSimpleSelect() throws SQLException {

String sql = "SELECT i.* FROM t_order o JOIN t_order_item i ON o.order_id=i.order_id";

try (HintManager hintManager = HintManager.getInstance();

Connection conn = dataSource.getConnection();

PreparedStatement preparedStatement = conn.prepareStatement(sql)) {

hintManager.addDatabaseShardingValue("t_order", "user_id", 11);

printSimpleSelect(preparedStatement);

}

}

private void printSimpleSelect(final PreparedStatement preparedStatement) throws SQLException {

StringBuilder builder = new StringBuilder();

try (ResultSet rs = preparedStatement.executeQuery()) {

while (rs.next()) {

System.out.print("order_item_id:" + rs.getLong(1) + ", ");

System.out.print("order_id:" + rs.getLong(2) + ", ");

System.out.print("user_id:" + rs.getInt(3));

System.out.println();

}

}

}

private void execute(final DataSource dataSource, final String sql) throws SQLException {

try (Connection conn = dataSource.getConnection(); Statement statement = conn.createStatement()) {

statement.execute(sql);

}

}

private long executeAndGetGeneratedKey(final DataSource dataSource, final String sql) throws SQLException {

long result = -1;

try (Connection conn = dataSource.getConnection(); Statement statement = conn.createStatement()) {

statement.executeUpdate(sql, Statement.RETURN_GENERATED_KEYS);

ResultSet resultSet = statement.getGeneratedKeys();

if (resultSet.next()) {

result = resultSet.getLong(1);

}

}

return result;

}

}