SLING-7540 LastIterator improvements
Removed pre-determination of the last item to make it more "lazy"
diff --git a/src/main/java/org/apache/sling/query/iterator/LastIterator.java b/src/main/java/org/apache/sling/query/iterator/LastIterator.java
index b02621f..2316b97 100644
--- a/src/main/java/org/apache/sling/query/iterator/LastIterator.java
+++ b/src/main/java/org/apache/sling/query/iterator/LastIterator.java
@@ -20,60 +20,42 @@
package org.apache.sling.query.iterator;
import java.util.Iterator;
-import java.util.ListIterator;
import org.apache.sling.query.api.internal.Option;
-import org.apache.sling.query.util.LazyList;
+/**
+ *
+ *
+ *
+ * @param <T>
+ */
public class LastIterator<T> extends AbstractIterator<Option<T>> {
- private final LazyList<Option<T>> lazyList;
+ private final Iterator<Option<T>> iterator;
- private final ListIterator<Option<T>> iterator;
-
- private boolean finished;
-
- private boolean initialized;
-
- private int lastIndex = -1;
+ private Option<T> previous;
public LastIterator(Iterator<Option<T>> iterator) {
- this.lazyList = new LazyList<Option<T>>(iterator);
- this.iterator = lazyList.listIterator();
+ this.iterator = iterator;
}
@Override
protected Option<T> getElement() {
- if (finished) {
- return null;
- }
-
- initializeLastIndex();
-
- Option<T> candidate;
- if (iterator.hasNext()) {
- candidate = iterator.next();
- } else {
- finished = true;
- return null;
- }
- if (iterator.previousIndex() == lastIndex) {
- finished = true;
+ Option<T> candidate = previous;
+
+ if (!iterator.hasNext()) {
+ previous = null;
return candidate;
- } else {
- return Option.empty(candidate.getArgumentId());
- }
- }
-
- private void initializeLastIndex() {
- ListIterator<Option<T>> i = lazyList.listIterator();
- if (!initialized) {
- while (i.hasNext()) {
- if (!i.next().isEmpty()) {
- lastIndex = i.previousIndex();
- }
+ }
+
+ if (candidate == null) {
+ candidate = iterator.next();
+ if (!iterator.hasNext()) {
+ return candidate;
}
}
- initialized = true;
+ previous = iterator.next();
+ return Option.empty(candidate.getArgumentId());
}
+
}
