flink-instrumentation/workspace/flink-1.4.1-instrumented/flink-1.4.1/flink-runtime/src/main/java/org/apache/flink/runtime/state/AbstractStateBackend.java
/**
	 * Loads the state backend from the configuration, from the parameter 'state.backend', as defined
	 * in {@link CoreOptions#STATE_BACKEND}. If no state backend is configures, this instantiates the
	 * default state backend (the {@link MemoryStateBackend}). 
	 *
	 * <p>Refer to {@link #loadStateBackendFromConfig(Configuration, ClassLoader, Logger)} for details on
	 * how the state backend is loaded from the configuration.
	 *
	 * @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
	 */
Loads the state backend from the configuration, from the parameter 'state.backend', as defined
in  CoreOptions#STATE_BACKEND. If no state backend is configures, this instantiates the
default state backend (the  MemoryStateBackend).

Refer to  #loadStateBackendFromConfig(Configuration, ClassLoader, Logger) for details on
how the state backend is loaded from the configuration.

@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
Loads the state backend from the configuration from the parameter ' state . backend ' as defined in CoreOptions#STATE_BACKEND . If no state backend is configures this instantiates the default state backend ( the MemoryStateBackend ) . Refer to #loadStateBackendFromConfig ( Configuration ClassLoader Logger ) for details on how the state backend is loaded from the configuration . @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 loadStateBackendFromConfigOrCreateDefault(
			Configuration config,
			ClassLoader classLoader,
			@Nullable Logger logger) throws IllegalConfigurationException, DynamicCodeLoadingException, IOException {
		final StateBackend fromConfig = loadStateBackendFromConfig(config, classLoader, logger);
		if (fromConfig != null) {
			return fromConfig;
		}
		else {
			if (logger != null) {
				logger.info("No state backend has been configured, using default state backend (Memory / JobManager)");
			}
			return new MemoryStateBackend();
		}
	}
public static StateBackend loadStateBackendFromConfigOrCreateDefault ( Configuration config , ClassLoader classLoader , @ Nullable Logger logger ) throws IllegalConfigurationException , DynamicCodeLoadingException , IOException { final StateBackend fromConfig = loadStateBackendFromConfig ( config , classLoader , logger ) ; if ( fromConfig != null ) { return fromConfig ; } else { if ( logger != null ) { logger . info ( "No state backend has been configured, using default state backend (Memory / JobManager)" ) ; } return new MemoryStateBackend ( ) ; } }
Loads the state backend from the configuration, from the parameter 'state.backend', as defined
 in {@link CoreOptions#STATE_BACKEND}.
Loads the state backend from the configuration from the parameter ' state . backend ' as defined in { @link CoreOptions#STATE_BACKEND } .