RedisIdEngine.java

package engine;

import org.apache.commons.lang3.StringUtils;

import com.github.ddth.id.RedisIdGenerator;
import com.github.ddth.id.SerialIdGenerator;

/**
 * Redis-implementation of {@link IIdEngine}.
 * 
 * <p>
 * IDs generated by this engine are:
 * <ul>
 * <li>Persistent: (*) backed by Redis.</li>
 * </ul>
 * <p/>
 * 
 * @author ThanhNB
 * @since 0.1.0
 */
public class RedisIdEngine extends BaseSerialIdEngine {

    private final static String DEFAULT_PREFIX = "id-server-";
    private String prefix = DEFAULT_PREFIX;

    protected String getPrefix() {
        return prefix;
    }

    public RedisIdEngine setPrefix(String prefix) {
        this.prefix = prefix;
        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected RedisIdGenerator getIdGenerator() {
        return (RedisIdGenerator) super.getIdGenerator();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public RedisIdEngine setIdGenerator(SerialIdGenerator idGenerator) {
        if (!(idGenerator instanceof RedisIdGenerator)) {
            final String errorMsg = "Argument must be of type [" + RedisIdGenerator.class.getName()
                    + "]!";
            throw new IllegalArgumentException(errorMsg);
        }
        super.setIdGenerator(idGenerator);
        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public RedisIdEngine init() {
        super.init();

        if (StringUtils.isBlank(prefix)) {
            prefix = DEFAULT_PREFIX;
        }
        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected String normalizeNamespace(final String namespace) {
        return prefix + namespace;
    }
}