74 lines
1.5 KiB
Java
74 lines
1.5 KiB
Java
package iterator;
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import exceptions.BoundaryViolationException;
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import position.Position;
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import position.PositionList;
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import java.util.Iterator;
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import java.util.NoSuchElementException;
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/**
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* Created with MONSTER.
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* User: xgiovio
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* Date: 06/04/2014
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* Time: 21:06
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*/
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//iterator implementation with cursor for PositionList data structures.
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public class ElementIterator<E> implements Iterator<E> {
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public ElementIterator (PositionList<E> structure){
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new_structure = structure;
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}
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@Override
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public boolean hasNext() {
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if (pos == null){
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if (new_structure. size() <= 0){
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return false;
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} else {
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return true;
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}
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} else {
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try {
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new_structure.next(pos);
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return true;
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}
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catch (BoundaryViolationException err){
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return false;
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}
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}
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}
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@Override
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public E next() throws NoSuchElementException {
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if (hasNext()){
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if (pos == null){
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pos = new_structure.first();
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}else {
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pos = new_structure.next(pos);
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}
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return pos.element();
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} else{
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throw new NoSuchElementException();
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}
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}
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@Override
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public void remove() {
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throw new UnsupportedOperationException ();
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}
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PositionList<E> new_structure = null;
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Position<E> pos = null;
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} |