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Diffstat (limited to 'jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/FilteringIterator.java')
-rw-r--r--jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/FilteringIterator.java135
1 files changed, 0 insertions, 135 deletions
diff --git a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/FilteringIterator.java b/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/FilteringIterator.java
deleted file mode 100644
index dd8230bf26..0000000000
--- a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/FilteringIterator.java
+++ /dev/null
@@ -1,135 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2005, 2008 Oracle. All rights reserved.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License v1.0, which accompanies this distribution
- * and is available at http://www.eclipse.org/legal/epl-v10.html.
- *
- * Contributors:
- * Oracle - initial API and implementation
- ******************************************************************************/
-package org.eclipse.jpt.utility.internal.iterators;
-
-import java.util.Iterator;
-import java.util.NoSuchElementException;
-
-import org.eclipse.jpt.utility.Filter;
-import org.eclipse.jpt.utility.internal.StringTools;
-
-/**
- * A <code>FilteringIterator</code> wraps another <code>Iterator</code>
- * and uses a <code>Filter</code> to determine which elements in the
- * nested iterator are to be returned by calls to <code>next()</code>.
- * <p>
- * As an alternative to building a <code>Filter</code>, a subclass
- * of <code>FilteringIterator</code> can override the
- * <code>accept(Object)</code> method.
- * <p>
- * One, possibly undesirable, side-effect of using this iterator is that
- * the nested iterator's <code>next()</code> method will be invoked
- * <em>before</em> the filtered iterator's <code>next()</code>
- * method is invoked. This is because the "next" element must be
- * checked for whether it is to be accepted before the filtered iterator
- * can determine whether it has a "next" element (i.e. that the
- * <code>hasNext()</code> method should return <code>true</code>).
- * This also prevents a filtered iterator from supporting the optional
- * <code>remove()</code> method.
- */
-public class FilteringIterator<E1, E2>
- implements Iterator<E2>
-{
- private final Iterator<? extends E1> nestedIterator;
- private final Filter<E1> filter;
- private E2 next;
- private boolean done;
-
-
- /**
- * Construct an iterator with the specified nested
- * iterator and a disabled filter.
- * Use this constructor if you want to override the
- * <code>accept(Object)</code> method instead of building
- * a <code>Filter</code>.
- */
- public FilteringIterator(Iterator<? extends E1> nestedIterator) {
- this(nestedIterator, Filter.Disabled.<E1>instance());
- }
-
- /**
- * Construct an iterator with the specified nested
- * iterator and filter.
- */
- public FilteringIterator(Iterator<? extends E1> nestedIterator, Filter<E1> filter) {
- super();
- this.nestedIterator = nestedIterator;
- this.filter = filter;
- this.loadNext();
- }
-
- public boolean hasNext() {
- return ! this.done;
- }
-
- public E2 next() {
- if (this.done) {
- throw new NoSuchElementException();
- }
- E2 result = this.next;
- this.loadNext();
- return result;
- }
-
- /**
- * Because we need to pre-load the next element
- * to be returned, we cannot support the <code>remove()</code>
- * method.
- */
- public void remove() {
- throw new UnsupportedOperationException();
- }
-
- /**
- * Load next with the next valid entry from the nested
- * iterator. If there are none, next is set to <code>END</code>.
- */
- private void loadNext() {
- this.done = true;
- while (this.nestedIterator.hasNext() && (this.done)) {
- E1 temp = this.nestedIterator.next();
- if (this.accept(temp)) {
- // assume that if the object was accepted it is of type E
- this.next = this.cast(temp);
- this.done = false;
- } else {
- this.next = null;
- this.done = true;
- }
- }
- }
-
- /**
- * We have to assume the filter will only "accept" objects that can
- * be cast to E2.
- */
- @SuppressWarnings("unchecked")
- private E2 cast(E1 o) {
- return (E2) o;
- }
-
- /**
- * Return whether the <code>FilteringIterator</code>
- * should return the specified next element from a call to the
- * <code>next()</code> method.
- * <p>
- * This method can be overridden by a subclass as an
- * alternative to building a <code>Filter</code>.
- */
- protected boolean accept(E1 o) {
- return this.filter.accept(o);
- }
-
- @Override
- public String toString() {
- return StringTools.buildToStringFor(this, this.nestedIterator);
- }
-
-}

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