Apache
/
commons-collections
mirror of https://github.com/apache/commons-collections.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Refactor to avoid unecessary instanceof call 

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/collections/trunk@131693 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Stephen Colebourne 2004-05-03 11:50:30 +00:00
parent 4eee185efd
commit 9a462e3990
1 changed files with 37 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

65
src/java/org/apache/commons/collections/iterators/ObjectGraphIterator.java
View File

@ -70,7 +70,7 @@ import org.apache.commons.collections.Transformer;
* more efficient (and convenient) than using nested for loops to extract a list.
*
* @since Commons Collections 3.1
* @version $Revision: 1.2 $ $Date: 2004/05/03 11:38:49 $
* @version $Revision: 1.3 $ $Date: 2004/05/03 11:50:30 $
*
* @author Stephen Colebourne
*/
@ -148,41 +148,19 @@ public class ObjectGraphIterator implements Iterator {
root = null;
}
} else {
findNext(currentIterator);
findNextByIterator(currentIterator);
}
}
/**
* Finds the next object in the iteration.
* Finds the next object in the iteration given any start object.
*
* @param value the value to start from
*/
protected void findNext(Object value) {
if (value instanceof Iterator) {
if (value != currentIterator) {
// recurse a level
if (currentIterator != null) {
stack.push(currentIterator);
}
currentIterator = (Iterator) value;
}
while (currentIterator.hasNext() && hasNext == false) {
Object next = currentIterator.next();
if (transformer != null) {
next = transformer.transform(next);
}
findNext(next);
}
if (hasNext) {
// next value found
} else if (stack.isEmpty()) {
// all iterators exhausted
} else {
// current iterator exhausted, go up a level
currentIterator = (Iterator) stack.pop();
findNext(currentIterator);
}
// need to examine this iterator
findNextByIterator((Iterator) value);
} else {
// next value found
currentValue = value;
@ -190,7 +168,38 @@ public class ObjectGraphIterator implements Iterator {
}
}
/**
* Finds the next object in the iteration given an iterator.
*
* @param iterator the iterator to start from
*/
protected void findNextByIterator(Iterator iterator) {
if (iterator != currentIterator) {
// recurse a level
if (currentIterator != null) {
stack.push(currentIterator);
}
currentIterator = iterator;
}
while (currentIterator.hasNext() && hasNext == false) {
Object next = currentIterator.next();
if (transformer != null) {
next = transformer.transform(next);
}
findNext(next);
}
if (hasNext) {
// next value found
} else if (stack.isEmpty()) {
// all iterators exhausted
} else {
// current iterator exhausted, go up a level
currentIterator = (Iterator) stack.pop();
findNextByIterator(currentIterator);
}
}
//-----------------------------------------------------------------------
/**
* Checks whether there are any more elements in the iteration to obtain.