GC.1 - Forest.java

package gc;

import java.util.ArrayList;

/**
 * A forest contains many trees. In this forest there are beeches and ashes.
 * @author hypesystem
 */
public class Forest {
    ArrayList<Tree> trees;

    public Forest() {
        trees = new ArrayList<Tree>();
    }

    /**
     * Initializes a forest with two beeches and two ashes. One beech is 3 years
     * old, one ash is 2 years old. The two remaining trees are 1 year old.
     */
    public void initialize() {
        trees.add(new Beech());
        trees.get(0).growOneYear();
        trees.get(0).growOneYear();
        trees.add(new Beech());
        trees.add(new Ash());
        trees.get(2).growOneYear();
        trees.add(new Ash());
    }

    /**
     * Makes the whole forest grow one year.
     */
    public void growOneYear() {
        for(Tree tree : trees) {
            tree.growOneYear();
        }
    }

    /**
     * Makes several years pass at once (instead of growing one year at a time)
     * for the whole forest.
     * @param n Amount of years the whole forest should grow
     * ---
     * Note: If growManyYears() is an alternative to calling growOneYear() many
     * times, there is no reason to call show() at each step, as the task
     * assumes. growOneYear() doesn't call show() either. Leaving show() out
     * minimizes output to what you really want to see.
     */
    public void growManyYears(int n) {
        if(n > 0) {
            for(int i = 0; i < n; i++) {
                for(Tree tree : trees) {
                    tree.growOneYear();
                }
            }
        }
        else System.out.println("Cannot grow 0 years or less");
    }

    /**
     * Shows the entire forest by calling the show() method of each tree.
     */
    public void show() {
        for(Tree tree : trees) {
            tree.show();
        }
    }

}