Examples with FsStateBackendFactory org.apache.flink.runtime.state.filesystem.FsStateBackendFactory used on opensource projects

Example 1 with FsStateBackendFactory

use of org.apache.flink.runtime.state.filesystem.FsStateBackendFactory in project flink by apache.

the class AbstractStateBackend method loadStateBackendFromConfig.

// ------------------------------------------------------------------------
//  Loading the state backend from a configuration 
// ------------------------------------------------------------------------
/**
	 * Loads the state backend from the configuration, from the parameter 'state.backend', as defined
	 * in {@link CoreOptions#STATE_BACKEND}.
	 * 
	 * <p>The state backends can be specified either via their shortcut name, or via the class name
	 * of a {@link StateBackendFactory}. If a StateBackendFactory class name is specified, the factory
	 * is instantiated (via its zero-argument constructor) and its
	 * {@link StateBackendFactory#createFromConfig(Configuration)} method is called.
	 *
	 * <p>Recognized shortcut names are '{@value AbstractStateBackend#MEMORY_STATE_BACKEND_NAME}',
	 * '{@value AbstractStateBackend#FS_STATE_BACKEND_NAME}', and
	 * '{@value AbstractStateBackend#ROCKSDB_STATE_BACKEND_NAME}'.
	 * 
	 * @param config The configuration to load the state backend from
	 * @param classLoader The class loader that should be used to load the state backend
	 * @param logger Optionally, a logger to log actions to (may be null)
	 * 
	 * @return The instantiated state backend.
	 * 
	 * @throws DynamicCodeLoadingException
	 *             Thrown if a state backend factory is configured and the factory class was not
	 *             found or the factory could not be instantiated
	 * @throws IllegalConfigurationException
	 *             May be thrown by the StateBackendFactory when creating / configuring the state
	 *             backend in the factory
	 * @throws IOException
	 *             May be thrown by the StateBackendFactory when instantiating the state backend
	 */
public static StateBackend loadStateBackendFromConfig(Configuration config, ClassLoader classLoader, @Nullable Logger logger) throws IllegalConfigurationException, DynamicCodeLoadingException, IOException {
    checkNotNull(config, "config");
    checkNotNull(classLoader, "classLoader");
    final String backendName = config.getString(CoreOptions.STATE_BACKEND);
    if (backendName == null) {
        return null;
    }
    // by default the factory class is the backend name 
    String factoryClassName = backendName;
    switch(backendName.toLowerCase()) {
        case MEMORY_STATE_BACKEND_NAME:
            if (logger != null) {
                logger.info("State backend is set to heap memory (checkpoint to JobManager)");
            }
            return new MemoryStateBackend();
        case FS_STATE_BACKEND_NAME:
            FsStateBackend fsBackend = new FsStateBackendFactory().createFromConfig(config);
            if (logger != null) {
                logger.info("State backend is set to heap memory (checkpoints to filesystem \"{}\")", fsBackend.getBasePath());
            }
            return fsBackend;
        case ROCKSDB_STATE_BACKEND_NAME:
            factoryClassName = "org.apache.flink.contrib.streaming.state.RocksDBStateBackendFactory";
        default:
            if (logger != null) {
                logger.info("Loading state backend via factory {}", factoryClassName);
            }
            StateBackendFactory<?> factory;
            try {
                @SuppressWarnings("rawtypes") Class<? extends StateBackendFactory> clazz = Class.forName(factoryClassName, false, classLoader).asSubclass(StateBackendFactory.class);
                factory = clazz.newInstance();
            } catch (ClassNotFoundException e) {
                throw new DynamicCodeLoadingException("Cannot find configured state backend factory class: " + backendName, e);
            } catch (ClassCastException | InstantiationException | IllegalAccessException e) {
                throw new DynamicCodeLoadingException("The class configured under '" + CoreOptions.STATE_BACKEND.key() + "' is not a valid state backend factory (" + backendName + ')', e);
            }
            return factory.createFromConfig(config);
    }
}