/*
 * Copyright 2015 the original author or authors.
 *
 * 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.statemachine.security;

import org.springframework.expression.Expression;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.util.Assert;

/**
 * Specific {@link ConfigAttribute} for spel expression.
 *
 * @author Janne Valkealahti
 *
 */
@SuppressWarnings("serial")
public class TransitionExpressionConfigAttribute implements ConfigAttribute {
	private final Expression authorizeExpression;

	/**
	 * Instantiates a new transition expression config attribute.
	 *
	 * @param authorizeExpression the authorize expression
	 */
	public TransitionExpressionConfigAttribute(Expression authorizeExpression) {
		Assert.notNull(authorizeExpression, "Expression must be set");
		this.authorizeExpression = authorizeExpression;
	}

	@Override
	public String getAttribute() {
		// always null
		return null;
	}

	/**
	 * Gets the authorize expression.
	 *
	 * @return the authorize expression
	 */
	Expression getAuthorizeExpression() {
		return authorizeExpression;
	}

	@Override
	public String toString() {
		return authorizeExpression.getExpressionString();
	}

}
