package logging;

import visualisation.HybridWindow;

import java.util.Vector;

/**
 * This class provides a container for log list elements. 
 * Use it in assoziation with packages logging and visualization. 
 * In general you will not have to extend this class so it is final. 
 * @see logging.Algorithm
 * @see logging.LogElement
 * @see HybridWindow
 * @see java.util.Vector
 * @author Bj�rn Strobel<br><small>
 * University of Cooperative Education Stuttgart, 
 * Campus Horb<br>
 * Department of Information Technology<br>
 * it2003<br></small>
 */
public final class LogElementList <LOG extends LogElement> extends Vector{
	
	/** Index of the Lists actual element.*/
	private int actual;
	/** Determines wether the log element list's index is valid or not.*/
	private boolean initialized;

	/**
	 * Standard constructor.
	 * Creates an empty uninitialized log list with index -1.
	 */
	public LogElementList() {
		super();
		actual=-1;
		initialized=false;
		// TODO Auto-generated constructor stub
	}
	
	/**
	 * Returns the log lists actual element identified by member actual.
	 * @return the log lists actual element
	 */
	public Object get(){
		return get(actual);
	}
	
	/**
	 * Returns wether the log element list is initialized or not.
	 * @return true if list is initialized, false if not
	 */
	public boolean isInitialized(){
		return initialized;
	}
	
	/**
	 * Clears the log list.
	 */
	public void clear(){
		super.clear();
		actual=-1;
		initialized=false;
	}
	
	/**
	 * Sets the actual's element's previous as actual.
	 */
	public void prev(){
		if(actual>0){
			actual--;}
		else{
			actual=0;}
		initialized=true;
	}
	
	/**
	 * Sets the actual's element's next as actual. 
	 */
	public void next(){
		if(actual<size()-1){
			actual++;}
		else{
			actual=size()-1;}
		initialized=true;
	}
	
	/**
	 * Sets the first element as actual.
	 */
	public void first(){
		actual=0;
		initialized=true;
	}
	
	/**
	 * Sets the last element as actual.
	 */
	public void last(){
		actual=size()-1;
		initialized=true;
	}
}