Pools.java

/*******************************************************************************
 * Copyright 2011 See AUTHORS file.
 * 
 * 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 com.badlogic.gdx.utils;

import chbachman.api.util.Array;
import chbachman.api.util.ObjectMap;

/**
 * Stores a map of {@link Pool}s (usually {@link ReflectionPool}s) by type for
 * convenient static access.
 * 
 * @author Nathan Sweet
 */
public class Pools {
    static private final ObjectMap<Class, Pool> typePools = new ObjectMap();

    /**
     * Returns a new or existing pool for the specified type, stored in a Class
     * to {@link Pool} map. Note the max size is ignored if this is not the
     * first time this pool has been requested.
     */
    static public <T> Pool<T> get(Class<T> type, int max) {
        Pool pool = typePools.get(type);
        if (pool == null) {
            pool = new ReflectionPool(type, 4, max);
            typePools.put(type, pool);
        }
        return pool;
    }

    /**
     * Returns a new or existing pool for the specified type, stored in a Class
     * to {@link Pool} map. The max size of the pool used is 100.
     */
    static public <T> Pool<T> get(Class<T> type) {
        return get(type, 100);
    }

    /**
     * Sets an existing pool for the specified type, stored in a Class to
     * {@link Pool} map.
     */
    static public <T> void set(Class<T> type, Pool<T> pool) {
        typePools.put(type, pool);
    }

    /** Obtains an object from the {@link #get(Class) pool}. */
    static public <T> T obtain(Class<T> type) {
        return get(type).obtain();
    }

    /** Frees an object from the {@link #get(Class) pool}. */
    static public void free(Object object) {
        if (object == null)
            throw new IllegalArgumentException("Object cannot be null.");
        Pool pool = typePools.get(object.getClass());
        if (pool == null)
            return; // Ignore freeing an object that was never retained.
        pool.free(object);
    }

    /**
     * Frees the specified objects from the {@link #get(Class) pool}. Null
     * objects within the array are silently ignored. Objects don't need to be
     * from the same pool.
     */
    static public void freeAll(Array objects) {
        freeAll(objects, false);
    }

    /**
     * Frees the specified objects from the {@link #get(Class) pool}. Null
     * objects within the array are silently ignored.
     * 
     * @param samePool
     *            If true, objects don't need to be from the same pool but the
     *            pool must be looked up for each object.
     */
    static public void freeAll(Array objects, boolean samePool) {
        if (objects == null)
            throw new IllegalArgumentException("Objects cannot be null.");
        Pool pool = null;
        for (int i = 0, n = objects.size; i < n; i++) {
            Object object = objects.get(i);
            if (object == null)
                continue;
            if (pool == null) {
                pool = typePools.get(object.getClass());
                if (pool == null)
                    continue; // Ignore freeing an object that was never
                              // retained.
            }
            pool.free(object);
            if (!samePool)
                pool = null;
        }
    }

    private Pools() {
    }
}