/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
 *
 * Licensed 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 org.springframework.security.authentication.dao;

import org.springframework.security.core.userdetails.UserDetails;

import org.springframework.beans.factory.InitializingBean;

/**
 * Uses a static system-wide <code>String</code> as the salt.
 * <P>
 * Does not supply a different salt for each
 * {@link org.springframework.security.core.userdetails.User}. This means users sharing
 * the same password will still have the same digested password. Of benefit is the
 * digested passwords will at least be more protected than if stored without any salt.
 * </p>
 *
 * @author Ben Alex
 */
public class SystemWideSaltSource implements SaltSource, InitializingBean {
	// ~ Instance fields
	// ================================================================================================

	private String systemWideSalt;

	// ~ Methods
	// ========================================================================================================

	public void afterPropertiesSet() throws Exception {
		if ((this.systemWideSalt == null) || "".equals(this.systemWideSalt)) {
			throw new IllegalArgumentException("A systemWideSalt must be set");
		}
	}

	public Object getSalt(UserDetails user) {
		return this.systemWideSalt;
	}

	public String getSystemWideSalt() {
		return this.systemWideSalt;
	}

	public void setSystemWideSalt(String systemWideSalt) {
		this.systemWideSalt = systemWideSalt;
	}

	/**
	 * Displays the system wide salt
	 * @since 4.0
	 * @return
	 */
	@Override
	public String toString() {
		return systemWideSalt;
	}
}
