高可用

类名称：org.apache.shardingsphere.dbdiscovery.api.config.DatabaseDiscoveryRuleConfiguration 可配置属性：
可配置属性：
引入 Maven 依赖

// 构建数据源 ds_0，ds_1，ds_2
Map<String, DataSource> dataSourceMap = new HashMap<>(3, 1);
dataSourceMap.put("ds_0", createDataSource1("primary_demo_ds"));
dataSourceMap.put("ds_2", createDataSource3("primary_demo_ds"));
DataSource dataSource = ShardingSphereDataSourceFactory.createDataSource("database_discovery_db", dataSourceMap, Arrays.asList(createDatabaseDiscoveryConfiguration(), createReadwriteSplittingConfiguration()), null);
private static DatabaseDiscoveryRuleConfiguration createDatabaseDiscoveryConfiguration() {
    return new DatabaseDiscoveryRuleConfiguration(Collections.singleton(dataSourceRuleConfiguration), createDiscoveryHeartbeats(), createDiscoveryTypes());
}
private static ReadwriteSplittingRuleConfiguration createReadwriteSplittingConfiguration() {
    ReadwriteSplittingDataSourceRuleConfiguration dataSourceConfiguration1 = new ReadwriteSplittingDataSourceRuleConfiguration("replica_ds", new DynamicReadwriteSplittingStrategyConfiguration("readwrite_ds", true), "");
    return new ReadwriteSplittingRuleConfiguration(Arrays.asList(dataSourceConfiguration1), Collections.emptyMap());
}
    Map<String, AlgorithmConfiguration> discoveryTypes = new HashMap<>(1， 1);
    Properties props = new Properties();
    discoveryTypes.put("mgr", new AlgorithmConfiguration("MGR", props));
    return discoveryTypes;
}
private static Map<String, DatabaseDiscoveryHeartBeatConfiguration> createDiscoveryHeartbeats() {
    Map<String, DatabaseDiscoveryHeartBeatConfiguration> discoveryHeartBeatConfiguration = new HashMap<>(1， 1);
    Properties props = new Properties();
    props.put("keep-alive-cron", "0/5 * * * * ?");
    discoveryHeartBeatConfiguration.put("mgr-heartbeat", new DatabaseDiscoveryHeartBeatConfiguration(props));
    return discoveryHeartBeatConfiguration;
}