ObjectPoolList.java

package org.maltparser.core.pool;

import java.util.ArrayList;
import org.maltparser.core.exception.MaltChainedException;

public abstract class ObjectPoolList<T> extends ObjectPool<T> {

    private final ArrayList<T> objectList;
    private int currentSize;

    public ObjectPoolList() {
        this(Integer.MAX_VALUE);
    }

    public ObjectPoolList(int keepThreshold) {
        super(keepThreshold);
        objectList = new ArrayList<T>();
    }

    protected abstract T create() throws MaltChainedException;

    public abstract void resetObject(T o) throws MaltChainedException;

    public synchronized T checkOut() throws MaltChainedException {
        T t;
        if (currentSize >= objectList.size()) {
            t = create();
            objectList.add(t);
            currentSize++;
        } else {
            t = objectList.get(currentSize);
            currentSize++;
        }
        return t;
    }

    public synchronized void checkIn(T o) throws MaltChainedException {
        resetObject(o);
    }

    public synchronized void checkInAll() throws MaltChainedException {
        for (int i = currentSize - 1; i >= 0 && i < objectList.size(); i--) {
            resetObject(objectList.get(i));
            if (currentSize >= keepThreshold) {
                objectList.remove(i);
            }
        }
        currentSize = 0;
    }

    public int getCurrentSize() {
        return currentSize;
    }

    public void setCurrentSize(int currentSize) {
        this.currentSize = currentSize;
    }

    public int size() {
        return objectList.size();
    }

    @Override
    public String toString() {
        final StringBuilder sb = new StringBuilder();
        for (int i = 0; i < currentSize; i++) {
            sb.append(objectList.get(i));
            sb.append(", ");
        }
        return sb.toString();
    }
}