UNIQUE_CORE.md

Unique Core

Dependency

To use the unique-core module, you need to include the unique-core-0.1.0.jar file and its dependencies in the classpath.

If you are using Maven just add the following dependency to your pom.xml:

<dependency>
    <groupId>io.leego</groupId>
    <artifactId>unique-core</artifactId>
    <version>0.1.0</version>
</dependency>

Getting Started

JDBC

Take MySQL as an example, you need to include the mysql-connector-java-x.x.x.jar file.

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>${mysql.version}</version>
</dependency>

Create a schema and table.

More Databases

create database `unique`;
use `unique`;
create table `sequence`
(
    `seq_key`         varchar(127) primary key     not null comment 'key',
    `seq_value`       bigint unsigned default 0    not null comment 'value',
    `seq_increment`   int unsigned    default 1    not null comment 'increment',
    `seq_cache`       int unsigned    default 5000 not null comment 'cache size',
    `seq_version`     int unsigned    default 1    not null comment 'version',
    `seq_create_time` timestamp                    null comment 'create time',
    `seq_update_time` timestamp                    null comment 'update time'
) engine = InnoDB
  default charset = utf8mb4
  collate utf8mb4_unicode_ci
    comment 'sequence';

Notice that the JdbcSequenceManagerImpl requires a DataSource. This can be any DataSource and should be configured.

String driverClassName = "com.mysql.cj.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/unique?serverTimezone=GMT";
String username = "username";
String password = "password";
String table = "sequence";
HikariConfig config = new HikariConfig();
config.setDriverClassName(driverClassName);
config.setJdbcUrl(url);
config.setUsername(username);
config.setPassword(password);
DataSource dataSource = new HikariDataSource(config);
SequenceManager sequenceManager = new JdbcSequenceManagerImpl(dataSource, table);

Use standalone mode.

SequenceService sequenceService = new StandaloneSequenceServiceImpl(sequenceManager);

Use cluster mode.

SequenceService sequenceService = new ClusterSequenceServiceImpl(sequenceManager);

MongoDB

You need to include the mongodb-driver-sync-x.x.x.jar file.

<dependency>
    <groupId>org.mongodb</groupId>
    <artifactId>mongodb-driver-sync</artifactId>
    <version>${mongodb.version}</version>
</dependency>

Notice that the MongoSequenceManagerImpl requires a MongoClient.

String uri = "mongodb://localhost:27017";
String username = "username";
String password = "password";
String database = "unique";
String collection = "sequence";
MongoCredential credential = MongoCredential.createCredential(
        username,
        database,
        password.toCharArray());
MongoClientSettings settings = MongoClientSettings.builder()
        .applyConnectionString(new ConnectionString(uri))
        .credential(credential)
        .build();
MongoClient mongoClient = MongoClients.create(settings);
SequenceManager sequenceManager = new MongoSequenceManagerImpl(mongoClient, database, collection);

Use standalone mode.

SequenceService sequenceService = new StandaloneSequenceServiceImpl(sequenceManager);

Use cluster mode.

SequenceService sequenceService = new ClusterSequenceServiceImpl(sequenceManager);

Use Client

See the unique-client for details.

Notice that the SimpleUniqueClient's performance is terrible in cluster mode, please use CachedUniqueClient instead of SimpleUniqueClient.

// SimpleUniqueClient
UniqueClient simpleClient = UniqueClients.newSimple(sequenceService);
// CachedUniqueClient
UniqueClient cachedClient = UniqueClients.newCached(sequenceService);