net.sf.staccatocommons.iterators.AppendThriterator Maven / Gradle / Ivy
/**
* Copyright (c) 2010-2012, The StaccatoCommons Team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*/
package net.sf.staccatocommons.iterators;
import java.util.Iterator;
import java.util.NoSuchElementException;
import net.sf.staccatocommons.defs.Thunk;
import net.sf.staccatocommons.iterators.thriter.AdvanceThriterator;
import net.sf.staccatocommons.iterators.thriter.Thriter;
import net.sf.staccatocommons.iterators.thriter.Thriterator;
import net.sf.staccatocommons.iterators.thriter.Thriterators;
import net.sf.staccatocommons.iterators.thriter.internal.ConstantThunk;
import net.sf.staccatocommons.restrictions.check.NonNull;
/**
* @author flbulgarelli
*
*/
public class AppendThriterator extends AdvanceThriterator {
private final Thriter iterator;
private final A element;
private boolean unconsumed = true;
/**
*
* Creates a new {@link AppendThriterator}
*/
public AppendThriterator(@NonNull Thriter iterator, A element) {
this.iterator = iterator;
this.element = element;
}
/**
*
* Creates a new {@link AppendThriterator}
*/
public AppendThriterator(@NonNull Iterator iterator, A element) {
this((Thriter) Thriterators.from(iterator), element);
}
/**
*
* Creates a new {@link AppendThriterator}
*/
public AppendThriterator(@NonNull Thriterator iterator, A element) {
this((Thriter) iterator, element);
}
public final boolean hasNext() {
if (iterator.hasNext())
return true;
return unconsumed;
}
public final void advanceNext() throws NoSuchElementException {
if (iterator.hasNext())
iterator.advanceNext();
else if (unconsumed)
unconsumed = false;
else
throw new NoSuchElementException();
}
public final A current() throws NoSuchElementException {
if (unconsumed)
return iterator.current();
return elementValue();
}
protected A elementValue() {
return element;
}
protected Thunk elementThunk() {
return new ConstantThunk(element);
}
public Thunk delayedCurrent() {
if (unconsumed)
return (Thunk) iterator.delayedCurrent();
return elementThunk();
}
}