SessionStorage.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.formio.data;

/**
 * Storage related to concrete application user.
 * Implementations must be immutable.
 * @author Radek Beran
 */
public interface SessionStorage {

	/**
	 * Sets the value and returns the value set.
	 * @param key
	 * @param value
	 * @return
	 */
	String set(String key, String value);
	
	/**
	 * Returns the value for given key or {@code null}.
	 * @param key
	 * @return
	 */
	String get(String key);
	
	/**
	 * Deletes the value with given key.
	 * @param key
	 * @return true if the value for given key was found
	 */
	boolean delete(String key);
}