/*
 * 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.
 */

/* $Id: ActionSet.java 1761021 2016-09-16 11:40:57Z ssteiner $ */

package org.apache.fop.render.intermediate.extensions;

import java.util.Map;

This class manages actions and action references. Some action (like GoToXYActions) cannot be fully resolved at the time they are needed, so they are deferred. This class helps manages the references and resolution. /**
 * This class manages actions and action references. Some action (like {@link GoToXYAction}s)
 * cannot be fully resolved at the time they are needed, so they are deferred. This class
 * helps manages the references and resolution.
 */
public class ActionSet {

    private int lastGeneratedID;
    private Map actionRegistry = new java.util.HashMap();

    
Generates a new synthetic ID for an action.
Params:
action – the action
Returns:
the generated ID/**
     * Generates a new synthetic ID for an action.
     * @param action the action
     * @return the generated ID
     */
    public synchronized String generateNewID(AbstractAction action) {
        this.lastGeneratedID++;
        String prefix = action.getIDPrefix();
        if (prefix == null) {
            throw new IllegalArgumentException("Action class is not compatible");
        }
        return prefix + this.lastGeneratedID;
    }

    
Returns the action with the given ID.
Params:
id – the ID
Returns:
the action or null if no action with this ID is stored/**
     * Returns the action with the given ID.
     * @param id the ID
     * @return the action or null if no action with this ID is stored
     */
    public AbstractAction get(String id) {
        return (AbstractAction)this.actionRegistry.get(id);
    }

    
Puts an action into the set and returns the normalized instance (another one if the given
one is equal to another.
Params:
action – the action
Returns:
the action instance that should be used in place of the given one/**
     * Puts an action into the set and returns the normalized instance (another one if the given
     * one is equal to another.
     * @param action the action
     * @return the action instance that should be used in place of the given one
     */
    public AbstractAction put(AbstractAction action) {
        if (!action.hasID()) {
            action.setID(generateNewID(action));
        }
        AbstractAction effAction = normalize(action);
        if (effAction == action) {
            this.actionRegistry.put(action.getID(), action);
        }
        return effAction;
    }

    
Clears the set.
/**
     * Clears the set.
     */
    public void clear() {
        this.actionRegistry.clear();
    }

    private AbstractAction normalize(AbstractAction action) {
        for (Object o : this.actionRegistry.values()) {
            AbstractAction a = (AbstractAction) o;
            if (a.isSame(action)) {
                return a;
            }
        }
        return action;
    }

}