Field.java

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.LinkedList;
import java.util.List;

public class Field implements Cloneable, Serializable {

	/**
	 * Numbers of sudoku
	 */
	public static int POSSIBILITIES = 9;

	protected boolean set;

	protected boolean initialSet;

	protected int value;

	public Field() {
		this.initialSet = false;
		this.set = false;

		remainingPos = new LinkedList();
		for (int i = 1; i <= POSSIBILITIES; i++) {
			remainingPos.add((Object) i);
		}
	}

	public Field(int value, boolean initialSet) {
		this.value = value;
		this.set = true;
		this.initialSet = initialSet;

		remainingPos = new LinkedList();
	}

	public Field(int value) {
		this.value = value;
		this.set = true;
		this.initialSet = false;

		remainingPos = new LinkedList();
	}

	/**
	 * 
	 * @return
	 */
	public int getValue() {
		return value;
	}

	/**
	 * 
	 * @return
	 */
	public boolean isInitialSet() {
		return initialSet;
	}

	/**
	 * 
	 * @return
	 */
	public boolean isSet() {
		return set;
	}

	// private static final long serialVersionUID = 1L;

	public Object clone() throws CloneNotSupportedException {
		Field clone = new Field();
		clone.initialSet = initialSet;
		clone.set = set;
		clone.value = value;
		LinkedList remainingPosClone = new LinkedList();
		for (int i = 0; i < remainingPos.size(); i++) {
			remainingPosClone.add(new Integer(((Integer) remainingPos.get(i))
					.intValue()));
		}
		clone.remainingPos = remainingPosClone;
		return clone;
	}

	private void writeObject(ObjectOutputStream aOutputStream)
			throws IOException {
		aOutputStream.writeBoolean(set);
		aOutputStream.writeBoolean(initialSet);
		aOutputStream.writeInt(value);
		aOutputStream.defaultWriteObject();
	}

	private void readObject(ObjectInputStream aInputStream)
			throws ClassNotFoundException, IOException {
		aInputStream.defaultReadObject();
		set = aInputStream.readBoolean();
		initialSet = aInputStream.readBoolean();
		value = aInputStream.readInt();
	}

	protected List remainingPos;

	public Field(List remainingPos) {
		this.remainingPos = remainingPos;
	}

	/**
	 * 
	 * @return
	 */
	public List getRemainingPos() {
		return remainingPos;
	}

	// fürs Testen
	public String toString() {
		String output = "";
		if (remainingPos.isEmpty()) {
			output = "[" + value + "]";
		} else {
			output = "{";
			for (int i = 0; i < remainingPos.size(); i++) {
				output += remainingPos.get(i).toString();
			}
			output += "}";
		}
		return output;
	}

	public void setInitial(boolean flag) {
		initialSet = flag;
	}

}