HVersionEnforcingClient.java

package com.xxx.metadata.hector;

import java.util.Map;

import me.prettyprint.cassandra.connection.client.HClient;
import me.prettyprint.cassandra.service.CassandraHost;
import me.prettyprint.cassandra.service.ExceptionsTranslator;
import me.prettyprint.cassandra.service.ExceptionsTranslatorImpl;

import org.apache.cassandra.thrift.Cassandra.Client;
import org.apache.cassandra.thrift.InvalidRequestException;
import org.apache.thrift.TException;

/**
 * Wrapper class for Cassandra client.
 * The only thing it adds is set_cql_version() call on open.
 *
 * @author Max Alexejev
 * Mar 13, 2013
 */
public class HVersionEnforcingClient implements HClient {

    private final HClient delegate;
    private final String cqlVersion;
    private final ExceptionsTranslator exceptionTranslator;

    public HVersionEnforcingClient(HClient delegate, String cqlVersion) {
        this.delegate = delegate;
        this.cqlVersion = cqlVersion;
        this.exceptionTranslator = new ExceptionsTranslatorImpl();
    }

    @Override
    public long getCreatedTime() {
        return delegate.getCreatedTime();
    }

    @Override
    public Client getCassandra() {
        return delegate.getCassandra();
    }

    @Override
    public Client getCassandra(String keyspaceNameArg) {
        return delegate.getCassandra(keyspaceNameArg);
    }

    @Override
    public HClient close() {
        return delegate.close();
    }

    @Override
    public HClient open() {
        final HClient client = delegate.open();
        try {
            client.getCassandra().set_cql_version(cqlVersion);
        } catch (TException | InvalidRequestException e) {
            throw exceptionTranslator.translate(e);
        }
        return client;
    }

    @Override
    public boolean isOpen() {
        return delegate.isOpen();
    }

    @Override
    public void startToUse() {
        delegate.startToUse();
    }

    @Override
    public long getSinceLastUsed() {
        return delegate.getSinceLastUsed();
    }

    @Override
    public CassandraHost getCassandraHost() {
        return delegate.getCassandraHost();
    }

    @Override
    public void setAuthenticated(Map<String, String> credentials) {
        delegate.setAuthenticated(credentials);
    }

    @Override
    public boolean isAlreadyAuthenticated(Map<String, String> credentials) {
        return delegate.isAlreadyAuthenticated(credentials);
    }

    @Override
    public void clearAuthentication() {
        delegate.clearAuthentication();
    }

    @Override
    public long getLastSuccessTime() {
        return delegate.getLastSuccessTime();
    }

    @Override
    public void updateLastSuccessTime() {
        delegate.updateLastSuccessTime();
    }

}