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Refactor CommonsLinkedList and NodeCachingLinkedList to list subpackage 

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/collections/trunk@131422 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Stephen Colebourne 2003-12-11 00:18:06 +00:00
parent c784488a2c
commit 1decf8b6fb
13 changed files with 1492 additions and 15 deletions
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src/java/org/apache/commons/collections/CommonsLinkedList.java
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@ -1,5 +1,5 @@
/* /*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/Attic/CommonsLinkedList.java,v 1.9 2003/10/09 20:58:52 scolebourne Exp $ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/Attic/CommonsLinkedList.java,v 1.10 2003/12/11 00:18:06 scolebourne Exp $
* ==================================================================== * ====================================================================
* *
* The Apache Software License, Version 1.1 * The Apache Software License, Version 1.1
@ -60,7 +60,6 @@ package org.apache.commons.collections;
import java.io.IOException; import java.io.IOException;
import java.io.ObjectInputStream; import java.io.ObjectInputStream;
import java.io.ObjectOutputStream; import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.lang.reflect.Array; import java.lang.reflect.Array;
import java.util.Collection; import java.util.Collection;
import java.util.ConcurrentModificationException; import java.util.ConcurrentModificationException;
@ -75,14 +74,15 @@ import java.util.NoSuchElementException;
* of {@link LinkedList}, but which provides a more open interface for * of {@link LinkedList}, but which provides a more open interface for
* subclasses to extend. * subclasses to extend.
* *
* @deprecated TO BE REMOVED BEFORE v3.0
* @since Commons Collections 3.0 * @since Commons Collections 3.0
* @version $Revision: 1.9 $ $Date: 2003/10/09 20:58:52 $ * @version $Revision: 1.10 $ $Date: 2003/12/11 00:18:06 $
* *
* @author Rich Dougherty * @author Rich Dougherty
* @author Phil Steitz * @author Phil Steitz
*/ */
class CommonsLinkedList extends LinkedList class CommonsLinkedList extends LinkedList
implements List, Serializable { implements List {
/* /*
* Implementation notes: * Implementation notes:

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src/java/org/apache/commons/collections/NodeCachingLinkedList.java
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@ -1,5 +1,5 @@
/* /*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/Attic/NodeCachingLinkedList.java,v 1.9 2003/10/09 20:58:52 scolebourne Exp $ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/Attic/NodeCachingLinkedList.java,v 1.10 2003/12/11 00:18:06 scolebourne Exp $
* ==================================================================== * ====================================================================
* *
* The Apache Software License, Version 1.1 * The Apache Software License, Version 1.1
@ -64,8 +64,9 @@ import java.util.Collection;
* unnecessary object creates and deletion. This should result in a performance * unnecessary object creates and deletion. This should result in a performance
* improvement. * improvement.
* *
* @deprecated TO BE REMOVED BEFORE v3.0
* @since Commons Collections 3.0 * @since Commons Collections 3.0
* @version $Revision: 1.9 $ $Date: 2003/10/09 20:58:52 $ * @version $Revision: 1.10 $ $Date: 2003/12/11 00:18:06 $
* *
* @author Jeff Varszegi * @author Jeff Varszegi
* @author <a href="mailto:rich@rd.gen.nz">Rich Dougherty</a> * @author <a href="mailto:rich@rd.gen.nz">Rich Dougherty</a>

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src/java/org/apache/commons/collections/list/AbstractLinkedList.java Normal file
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/*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/list/AbstractLinkedList.java,v 1.1 2003/12/11 00:18:06 scolebourne Exp $
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.commons.collections.list;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.reflect.Array;
import java.util.AbstractList;
import java.util.Collection;
import java.util.ConcurrentModificationException;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import java.util.NoSuchElementException;
import org.apache.commons.collections.OrderedIterator;
/**
* An abstract implementation of a linked list which provides numerous points for
* subclasses to override.
* <p>
* Overridable methods are provided to change the storage node, and to change how
* entries are added to and removed from the map. Hopefully, all you need for
* unusual subclasses is here.
* <p>
* This class currently extends AbstractList, but do not rely on that. It may change.
*
* @since Commons Collections 3.0
* @version $Revision: 1.1 $ $Date: 2003/12/11 00:18:06 $
*
* @author Rich Dougherty
* @author Phil Steitz
* @author Stephen Colebourne
*/
public abstract class AbstractLinkedList extends AbstractList implements List {
/*
* Implementation notes:
* - a standard circular doubly-linked list
* - a marker node is stored to mark the start and the end of the list
* - node creation and removal always occurs through createNode() and
* removeNode().
* - a modification count is kept, with the same semantics as
* {@link java.util.LinkedList}.
* - respects {@link AbstractList#modCount}
* - only extends AbstractList for subList() - TODO
*/
/**
* A {@link Node} which indicates the start and end of the list and does not
* hold a value. The value of <code>next</code> is the first item in the
* list. The value of of <code>previous</code> is the last item in the list.
*/
protected transient Node header;
/** The size of the list */
protected transient int size;
// /** Modification count for iterators */
// protected transient int modCount;
/**
* Constructor that does nothing intended for deserialization.
* <p>
* If this constructor is used by a serializable subclass then the init()
* method must be called.
*/
protected AbstractLinkedList() {
super();
}
/**
* Constructs a list copying data from the specified collection.
*
* @param coll the collection to copy
*/
protected AbstractLinkedList(Collection coll) {
super();
init();
addAll(coll);
}
/**
* The equivalent of a default constructor, broken out so it can be called
* by any constructor and by <code>readObject</code>.
* Subclasses which override this method should make sure they call super,
* so the list is initialised properly.
*/
protected void init() {
header = createHeaderNode();
}
//-----------------------------------------------------------------------
public int size() {
return size;
}
public boolean isEmpty() {
return (size() == 0);
}
public Object get(int index) {
Node node = getNode(index, false);
return node.value;
}
//-----------------------------------------------------------------------
public Iterator iterator() {
return listIterator();
}
public ListIterator listIterator() {
return new LinkedListIterator();
}
public ListIterator listIterator(int startIndex) {
return new LinkedListIterator(startIndex);
}
//-----------------------------------------------------------------------
public int indexOf(Object value) {
int i = 0;
for (Node node = header.next; node != header; node = node.next) {
if (isEqualValue(node.value, value)) {
return i;
}
i++;
}
return -1;
}
public int lastIndexOf(Object value) {
int i = size - 1;
for (Node node = header.previous; node != header; node = node.previous) {
if (isEqualValue(node.value, value)) {
return i;
}
i--;
}
return -1;
}
public boolean contains(Object value) {
return indexOf(value) != -1;
}
public boolean containsAll(Collection coll) {
Iterator it = coll.iterator();
while (it.hasNext()) {
if (contains(it.next()) == false) {
return false;
}
}
return true;
}
//-----------------------------------------------------------------------
public boolean add(Object value) {
addLast(value);
return true;
}
public void add(int index, Object value) {
Node node = getNode(index, true);
addNodeBefore(node, value);
}
public boolean addAll(Collection coll) {
return addAll(size, coll);
}
public boolean addAll(int index, Collection coll) {
Node node = getNode(index, true);
for (Iterator itr = coll.iterator(); itr.hasNext();) {
Object value = itr.next();
addNodeBefore(node, value);
}
return true;
}
//-----------------------------------------------------------------------
public Object remove(int index) {
Node node = getNode(index, false);
Object oldValue = node.value;
removeNode(node);
return oldValue;
}
public boolean remove(Object value) {
for (Node node = header.next; node != header; node = node.next) {
if (isEqualValue(node.value, value)) {
removeNode(node);
return true;
}
}
return false;
}
public boolean removeAll(Collection coll) {
boolean modified = false;
Iterator it = iterator();
while (it.hasNext()) {
if (coll.contains(it.next())) {
it.remove();
modified = true;
}
}
return modified;
}
//-----------------------------------------------------------------------
public boolean retainAll(Collection coll) {
boolean modified = false;
Iterator it = iterator();
while (it.hasNext()) {
if (coll.contains(it.next()) == false) {
it.remove();
modified = true;
}
}
return modified;
}
public Object set(int index, Object value) {
Node node = getNode(index, false);
Object oldValue = node.value;
node.value = value;
return oldValue;
}
public void clear() {
removeAllNodes();
}
//-----------------------------------------------------------------------
public Object[] toArray() {
return toArray(new Object[size]);
}
public Object[] toArray(Object[] array) {
// Extend the array if needed
if (array.length < size) {
Class componentType = array.getClass().getComponentType();
array = (Object[]) Array.newInstance(componentType, size);
}
// Copy the values into the array
Node node = header.next;
for (int i = 0; i < size; i++) {
array[i] = node.value;
node = node.next;
}
// Set the value after the last value to null
if (array.length > size) {
array[size] = null;
}
return array;
}
//-----------------------------------------------------------------------
public Object getFirst() {
Node node = header.next;
if (node == header) {
throw new NoSuchElementException();
}
return node.value;
}
public Object getLast() {
Node node = header.previous;
if (node == header) {
throw new NoSuchElementException();
}
return node.value;
}
public void addFirst(Object o) {
addNodeAfter(header, o);
}
public void addLast(Object o) {
addNodeBefore(header, o);
}
public Object removeFirst() {
Node node = header.next;
if (node == header) {
throw new NoSuchElementException();
}
Object oldValue = node.value;
removeNode(node);
return oldValue;
}
public Object removeLast() {
Node node = header.previous;
if (node == header) {
throw new NoSuchElementException();
}
Object oldValue = node.value;
removeNode(node);
return oldValue;
}
//-----------------------------------------------------------------------
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (obj instanceof List == false) {
return false;
}
List other = (List) obj;
if (other.size() != size()) {
return false;
}
ListIterator it1 = listIterator();
ListIterator it2 = other.listIterator();
while (it1.hasNext() && it2.hasNext()) {
Object o1 = it1.next();
Object o2 = it2.next();
if (!(o1 == null ? o2 == null : o1.equals(o2)))
return false;
}
return !(it1.hasNext() || it2.hasNext());
}
public int hashCode() {
int hashCode = 1;
Iterator it = iterator();
while (it.hasNext()) {
Object obj = it.next();
hashCode = 31 * hashCode + (obj == null ? 0 : obj.hashCode());
}
return hashCode;
}
public String toString() {
if (size() == 0) {
return "[]";
}
StringBuffer buf = new StringBuffer(16 * size());
buf.append("[");
Iterator it = iterator();
boolean hasNext = it.hasNext();
while (hasNext) {
Object value = it.next();
buf.append(value == this ? "(this Collection)" : value);
hasNext = it.hasNext();
if (hasNext) {
buf.append(", ");
}
}
buf.append("]");
return buf.toString();
}
//-----------------------------------------------------------------------
/**
* Compares two values for equals.
* This implementation uses the equals method.
* Subclasses can override this to match differently.
*
* @param value1 the first value to compare, may be null
* @param value2 the second value to compare, may be null
* @return true if equal
*/
protected boolean isEqualValue(Object value1, Object value2) {
return (value1 == value2 || (value1 == null ? false : value1.equals(value2)));
}
/**
* Creates a new node with previous, next and element all set to null.
* This implementation creates a new empty Node.
* Subclasses can override this to create a different class.
*
* @return newly created node
*/
protected Node createHeaderNode() {
return new Node();
}
/**
* Creates a new node with the specified properties.
* This implementation creates a new Node with data.
* Subclasses can override this to create a different class.
*
* @param previous node to precede the new node
* @param next node to follow the new node
* @param value value of the new node
*/
protected Node createNode(Node previous, Node next, Object value) {
return new Node(previous, next, value);
}
/**
* Creates a new node with the specified object as its
* <code>value</code> and inserts it before <code>node</code>.
*
* @param node node to insert before
* @param value value of the newly added node
* @throws NullPointerException if <code>node</code> is null
*/
protected void addNodeBefore(Node node, Object value) {
Node newNode = createNode(node.previous, node, value);
node.previous.next = newNode;
node.previous = newNode;
size++;
modCount++;
}
/**
* Creates a new node with the specified object as its
* <code>value</code> and inserts it after <code>node</code>.
*
* @param node node to insert after
* @param value value of the newly added node
* @throws NullPointerException if <code>node</code> is null
*/
protected void addNodeAfter(Node node, Object value) {
Node newNode = createNode(node, node.next, value);
node.next.previous = newNode;
node.next = newNode;
size++;
modCount++;
}
/**
* Removes the specified node from the list.
*
* @param node the node to remove
* @throws NullPointerException if <code>node</code> is null
*/
protected void removeNode(Node node) {
node.previous.next = node.next;
node.next.previous = node.previous;
size--;
modCount++;
}
/**
* Removes all nodes by resetting the circular list marker.
*/
protected void removeAllNodes() {
header.next = header;
header.previous = header;
size = 0;
modCount++;
}
/**
* Gets the node at a particular index.
*
* @param index the index, starting from 0
* @param endMarkerAllowed whether or not the end marker can be returned if
* startIndex is set to the list's size
* @throws IndexOutOfBoundsException if the index is less than 0; equal to
* the size of the list and endMakerAllowed is false; or greater than the
* size of the list
*/
protected Node getNode(int index, boolean endMarkerAllowed) throws IndexOutOfBoundsException {
// Check the index is within the bounds
if (index < 0) {
throw new IndexOutOfBoundsException("Couldn't get the node: " +
"index (" + index + ") less than zero.");
}
if (!endMarkerAllowed && index == size) {
throw new IndexOutOfBoundsException("Couldn't get the node: " +
"index (" + index + ") is the size of the list.");
}
if (index > size) {
throw new IndexOutOfBoundsException("Couldn't get the node: " +
"index (" + index + ") greater than the size of the " +
"list (" + size + ").");
}
// Search the list and get the node
Node node;
if (index < (size / 2)) {
// Search forwards
node = header.next;
for (int currentIndex = 0; currentIndex < index; currentIndex++) {
node = node.next;
}
} else {
// Search backwards
node = header;
for (int currentIndex = size; currentIndex > index; currentIndex--) {
node = node.previous;
}
}
return node;
}
//-----------------------------------------------------------------------
/**
* Serializes the data held in this object to the stream specified.
* <p>
* The first serializable subclass must call this method from
* <code>writeObject</code>.
*/
protected void doWriteObject(ObjectOutputStream outputStream) throws IOException {
// Write the size so we know how many nodes to read back
outputStream.writeInt(size());
for (Iterator itr = iterator(); itr.hasNext();) {
outputStream.writeObject(itr.next());
}
}
/**
* Deserializes the data held in this object to the stream specified.
* <p>
* The first serializable subclass must call this method from
* <code>readObject</code>.
*/
protected void doReadObject(ObjectInputStream inputStream) throws IOException, ClassNotFoundException {
init();
int size = inputStream.readInt();
for (int i = 0; i < size; i++) {
add(inputStream.readObject());
}
}
//-----------------------------------------------------------------------
/**
* A node within the linked list.
*
* @author Rich Dougherty
* @author Stephen Colebourne
*/
protected static class Node {
/** A pointer to the node before this node */
public Node previous;
/** A pointer to the node after this node */
public Node next;
/** The object contained within this node */
public Object value;
/**
* Constructs a new header node.
*/
public Node() {
super();
previous = this;
next = this;
}
/**
* Constructs a new node.
*
* @param previous the previous node in the list
* @param next the next node in the list
* @param value the value to store
*/
public Node(Node previous, Node next, Object value) {
super();
this.previous = previous;
this.next = next;
this.value = value;
}
}
//-----------------------------------------------------------------------
/**
* A list iterator over the linked list.
*
* @author Rich Dougherty
*/
protected class LinkedListIterator implements ListIterator, OrderedIterator {
/**
* The node that will be returned by {@link #next()}. If this is equal
* to {@link #marker} then there are no more values to return.
*/
protected Node nextNode;
/**
* The index of {@link #nextNode}.
*/
protected int nextIndex;
/**
* The last node that was returned by {@link #next()} or {@link
* #previous()}. Set to <code>null</code> if {@link #next()} or {@link
* #previous()} haven't been called, or if the node has been removed
* with {@link #remove()} or a new node added with {@link #add(Object)}.
* Should be accesed through {@link #getLastNodeReturned()} to enforce
* this behaviour.
*/
protected Node lastNodeReturned;
/**
* The modification count that the list is expected to have. If the list
* doesn't have this count, then a
* {@link java.util.ConcurrentModificationException} may be thrown by
* the operations.
*/
protected int expectedModCount;
/**
* Create a ListIterator for a list, starting at the first value in
* the list.
*/
public LinkedListIterator() throws IndexOutOfBoundsException {
this(0);
}
/**
* Create a ListIterator for a list.
*
* @param startIndex The index to start at.
*/
public LinkedListIterator(int startIndex) throws IndexOutOfBoundsException {
super();
expectedModCount = modCount;
nextNode = getNode(startIndex, true);
nextIndex = startIndex;
}
/**
* Checks the modification count of the list is the value that this
* object expects.
*
* @throws ConcurrentModificationException If the list's modification
* count isn't the value that was expected.
*/
protected void checkModCount()
throws ConcurrentModificationException {
if (modCount != expectedModCount) {
throw new ConcurrentModificationException();
}
}
/**
* Gets the last node returned.
*
* @throws IllegalStateException If {@link #next()} or
* {@link #previous()} haven't been called, or if the node has been removed
* with {@link #remove()} or a new node added with {@link #add(Object)}.
*/
protected Node getLastNodeReturned() throws IllegalStateException {
if (lastNodeReturned == null) {
throw new IllegalStateException();
}
return lastNodeReturned;
}
public boolean hasNext() {
return nextNode != header;
}
public Object next() {
checkModCount();
if (!hasNext()) {
throw new NoSuchElementException("No element at index " +
nextIndex + ".");
}
Object value = nextNode.value;
lastNodeReturned = nextNode;
nextNode = nextNode.next;
nextIndex++;
return value;
}
public boolean hasPrevious() {
return nextNode.previous != header;
}
public Object previous() {
checkModCount();
if (!hasPrevious()) {
throw new NoSuchElementException("Already at start of list.");
}
nextNode = nextNode.previous;
Object value = nextNode.value;
lastNodeReturned = nextNode;
nextIndex--;
return value;
}
public int nextIndex() {
return nextIndex;
}
public int previousIndex() {
return nextIndex - 1;
}
public void remove() {
checkModCount();
removeNode(getLastNodeReturned());
lastNodeReturned = null;
nextIndex--;
expectedModCount++;
}
public void set(Object o) {
checkModCount();
getLastNodeReturned().value = o;
}
public void add(Object o) {
checkModCount();
addNodeBefore(nextNode, o);
lastNodeReturned = null;
nextIndex++;
expectedModCount++;
}
}
}

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src/java/org/apache/commons/collections/list/NodeCachingLinkedList.java Normal file
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@ -0,0 +1,277 @@
/*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/java/org/apache/commons/collections/list/NodeCachingLinkedList.java,v 1.1 2003/12/11 00:18:06 scolebourne Exp $
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.commons.collections.list;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Collection;
/**
* A linked list implementation that caches the nodes used internally to prevent
* unnecessary object creates and deletion. This results in a performance
* improvement for long-lived lists which both add and remove.
*
* @since Commons Collections 3.0
* @version $Revision: 1.1 $ $Date: 2003/12/11 00:18:06 $
*
* @author Jeff Varszegi
* @author Rich Dougherty
* @author Phil Steitz
* @author Stephen Colebourne
*/
public class NodeCachingLinkedList extends AbstractLinkedList implements Serializable {
/** Serialization version */
static final long serialVersionUID = 6897789178562232073L;
/**
* The default value for {@link #maximumCacheSize}.
*/
protected static final int DEFAULT_MAXIMUM_CACHE_SIZE = 20;
/**
* The first cached node, or <code>null</code> if no nodes are cached.
* Cached nodes are stored in a singly-linked list with {@link Node#next}
* pointing to the next element.
*/
protected transient Node firstCachedNode;
/**
* The size of the cache.
*/
protected transient int cacheSize;
/**
* The maximum size of the cache.
*/
protected int maximumCacheSize;
//-----------------------------------------------------------------------
/**
* Constructor that creates.
*/
public NodeCachingLinkedList() {
this(DEFAULT_MAXIMUM_CACHE_SIZE);
}
/**
* Constructor that copies the specified collection
*
* @param coll the collection to copy
*/
public NodeCachingLinkedList(Collection coll) {
super(coll);
this.maximumCacheSize = DEFAULT_MAXIMUM_CACHE_SIZE;
}
/**
* Constructor that species the maximum cache size.
*
* @param maximumCacheSize the maximum cache size
*/
public NodeCachingLinkedList(int maximumCacheSize) {
super();
this.maximumCacheSize = maximumCacheSize;
init(); // must call init() as use super();
}
//-----------------------------------------------------------------------
/**
* Gets the maximum size of the cache.
*/
protected int getMaximumCacheSize() {
return maximumCacheSize;
}
/**
* Sets the maximum size of the cache.
*/
protected void setMaximumCacheSize(int maximumCacheSize) {
this.maximumCacheSize = maximumCacheSize;
shrinkCacheToMaximumSize();
}
/**
* Reduce the size of the cache to the maximum, if necessary.
*/
protected void shrinkCacheToMaximumSize() {
// Rich Dougherty: This could be more efficient.
while (cacheSize > maximumCacheSize) {
getNodeFromCache();
}
}
/**
* Gets a node from the cache. If a node is returned, then the value of
* {@link #cacheSize} is decreased accordingly. The node that is returned
* will have <code>null</code> values for next, previous and element.
*
* @return A node, or <code>null</code> if there are no nodes in the cache.
*/
protected Node getNodeFromCache() {
if (cacheSize == 0) {
return null;
}
Node cachedNode = firstCachedNode;
firstCachedNode = cachedNode.next;
cachedNode.next = null; // This should be changed anyway, but defensively
// set it to null.
cacheSize--;
return cachedNode;
}
protected boolean isCacheFull() {
return cacheSize >= maximumCacheSize;
}
/**
* Adds a node to the cache, if the cache isn't full. The node's contents
* are cleared to so they can be garbage collected.
*/
protected void addNodeToCache(Node node) {
if (isCacheFull()) {
// Don't cache the node.
return;
}
// Clear the node's contents and add it to the cache.
Node nextCachedNode = firstCachedNode;
node.previous = null;
node.next = nextCachedNode;
node.value = null;
firstCachedNode = node;
cacheSize++;
}
//-----------------------------------------------------------------------
/**
* Create a node, getting it from the cache if possible.
*/
protected Node createHeaderNode() {
Node cachedNode = getNodeFromCache();
if (cachedNode == null) {
return super.createHeaderNode();
} else {
return cachedNode;
}
}
/**
* Creates a new node with the specified properties, using a cached Node
* if possible.
*
* @param previous node to precede the new node
* @param next node to follow the new node
* @param value value of the new node
*/
protected Node createNode(Node previous, Node next, Object value) {
Node cachedNode = getNodeFromCache();
if (cachedNode == null) {
return super.createNode(previous, next, value);
} else {
cachedNode.next = next;
cachedNode.previous = previous;
cachedNode.value = value;
return cachedNode;
}
}
/**
* Calls the superclass' implementation then calls
* <code>addNodeToCache</code> on the node which has
* been removed.
*/
protected void removeNode(Node node) {
super.removeNode(node);
addNodeToCache(node);
}
protected void removeAllNodes() {
// Add the removed nodes to the cache, then remove the rest.
// We can add them to the cache before removing them, since
// {@link AbstractLinkedList.removeAllNodes()} removes the
// nodes by removing references directly from {@link #header}.
int numberOfNodesToCache = Math.min(size, maximumCacheSize - cacheSize);
Node node = header.next;
for (int currentIndex = 0; currentIndex < numberOfNodesToCache; currentIndex++) {
Node oldNode = node;
node = node.next;
addNodeToCache(oldNode);
}
super.removeAllNodes();
}
//-----------------------------------------------------------------------
/**
* Serializes the data held in this object to the stream specified.
*/
private void writeObject(ObjectOutputStream out) throws IOException {
out.defaultWriteObject();
doWriteObject(out);
}
/**
* Deserializes the data held in this object to the stream specified.
*/
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
doReadObject(in);
}
}

11
src/java/org/apache/commons/collections/list/package.html
View File

@ -2,12 +2,13 @@
<p> <p>
This package contains implementations of the List interface. This package contains implementations of the List interface.
<p> <p>
The implementations are in the form of direct implementations and decorators.
A decorator wraps another implementation of the interface to add some
specific additional functionality.
<p>
The following implementations are provided in the package: The following implementations are provided in the package:
<ul> <ul>
<li>NodeCachingLinkedList - a linked list that caches the storage nodes for a performance gain
</ul>
<p>
The following decorators are provided in the package:
<ul>
<li>Synchronized - synchronizes method access for multi-threaded environments <li>Synchronized - synchronizes method access for multi-threaded environments
<li>Unmodifiable - ensures the collection cannot be altered <li>Unmodifiable - ensures the collection cannot be altered
<li>Predicated - ensures that only elements that are valid according to a predicate can be added <li>Predicated - ensures that only elements that are valid according to a predicate can be added
@ -15,7 +16,7 @@ The following implementations are provided in the package:
<li>Transformed - transforms each element added <li>Transformed - transforms each element added
<li>FixedSize - ensures that the size of the list cannot change <li>FixedSize - ensures that the size of the list cannot change
<li>Lazy - creates objects in the list on demand <li>Lazy - creates objects in the list on demand
<li>Set - a list that avoids duplicate entries like a Set <li>SetUnique - a list that avoids duplicate entries like a Set
</ul> </ul>
</pre> </pre>
</BODY> </BODY>

13
src/test/org/apache/commons/collections/TestCommonsLinkedList.java
View File

@ -1,5 +1,5 @@
/* /*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/test/org/apache/commons/collections/Attic/TestCommonsLinkedList.java,v 1.7 2003/10/06 21:02:50 scolebourne Exp $ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/test/org/apache/commons/collections/Attic/TestCommonsLinkedList.java,v 1.8 2003/12/11 00:18:06 scolebourne Exp $
* ==================================================================== * ====================================================================
* *
* The Apache Software License, Version 1.1 * The Apache Software License, Version 1.1
@ -65,7 +65,7 @@ import junit.framework.Test;
/** /**
* Test case for {@link CommonsLinkedList}. * Test case for {@link CommonsLinkedList}.
* *
* @version $Revision: 1.7 $ $Date: 2003/10/06 21:02:50 $ * @version $Revision: 1.8 $ $Date: 2003/12/11 00:18:06 $
* *
* @author Rich Dougherty * @author Rich Dougherty
* @author David Hay * @author David Hay
@ -91,6 +91,15 @@ public class TestCommonsLinkedList extends TestLinkedList {
return "3"; return "3";
} }
protected boolean skipSerializedCanonicalTests() {
return true;
}
public void testCanonicalEmptyCollectionExists() {
}
public void testCanonicalFullCollectionExists() {
}
public void setUp() { public void setUp() {
list = (CommonsLinkedList)makeEmptyList(); list = (CommonsLinkedList)makeEmptyList();
} }

224
src/test/org/apache/commons/collections/list/TestAbstractLinkedList.java Normal file
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@ -0,0 +1,224 @@
/*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/test/org/apache/commons/collections/list/TestAbstractLinkedList.java,v 1.1 2003/12/11 00:18:06 scolebourne Exp $
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.commons.collections.list;
import java.util.Arrays;
/**
* Test case for {@link AbstractLinkedList}.
*
* @version $Revision: 1.1 $ $Date: 2003/12/11 00:18:06 $
*
* @author Rich Dougherty
* @author David Hay
* @author Phil Steitz
*/
public abstract class TestAbstractLinkedList extends AbstractTestList {
public TestAbstractLinkedList(String testName) {
super(testName);
}
//-----------------------------------------------------------------------
public void testRemoveFirst() {
resetEmpty();
AbstractLinkedList list = (AbstractLinkedList) collection;
if (isRemoveSupported() == false) {
try {
list.removeFirst();
} catch (UnsupportedOperationException ex) {}
}
list.addAll( Arrays.asList( new String[]{"value1", "value2"}));
assertEquals( "value1", list.removeFirst() );
checkNodes();
list.addLast( "value3");
checkNodes();
assertEquals( "value2", list.removeFirst() );
assertEquals( "value3", list.removeFirst() );
checkNodes();
list.addLast( "value4" );
checkNodes();
assertEquals( "value4", list.removeFirst() );
checkNodes();
}
public void testRemoveLast() {
resetEmpty();
AbstractLinkedList list = (AbstractLinkedList) collection;
if (isRemoveSupported() == false) {
try {
list.removeLast();
} catch (UnsupportedOperationException ex) {}
}
list.addAll( Arrays.asList( new String[]{"value1", "value2"}));
assertEquals( "value2", list.removeLast() );
list.addFirst( "value3");
checkNodes();
assertEquals( "value1", list.removeLast() );
assertEquals( "value3", list.removeLast() );
list.addFirst( "value4" );
checkNodes();
assertEquals( "value4", list.removeFirst() );
}
public void testAddNodeAfter() {
resetEmpty();
AbstractLinkedList list = (AbstractLinkedList) collection;
if (isAddSupported() == false) {
try {
list.addFirst(null);
} catch (UnsupportedOperationException ex) {}
}
list.addFirst("value1");
list.addNodeAfter(list.getNode(0,false),"value2");
assertEquals("value1", list.getFirst());
assertEquals("value2", list.getLast());
list.removeFirst();
checkNodes();
list.addNodeAfter(list.getNode(0,false),"value3");
checkNodes();
assertEquals("value2", list.getFirst());
assertEquals("value3", list.getLast());
list.addNodeAfter(list.getNode(0, false),"value4");
checkNodes();
assertEquals("value2", list.getFirst());
assertEquals("value3", list.getLast());
assertEquals("value4", list.get(1));
list.addNodeAfter(list.getNode(2, false), "value5");
checkNodes();
assertEquals("value2", list.getFirst());
assertEquals("value4", list.get(1));
assertEquals("value3", list.get(2));
assertEquals("value5", list.getLast());
}
public void testRemoveNode() {
resetEmpty();
if (isAddSupported() == false || isRemoveSupported() == false) return;
AbstractLinkedList list = (AbstractLinkedList) collection;
list.addAll( Arrays.asList( new String[]{"value1", "value2"}));
list.removeNode(list.getNode(0, false));
checkNodes();
assertEquals("value2", list.getFirst());
assertEquals("value2", list.getLast());
list.addFirst("value1");
list.addFirst("value0");
checkNodes();
list.removeNode(list.getNode(1, false));
assertEquals("value0", list.getFirst());
assertEquals("value2", list.getLast());
checkNodes();
list.removeNode(list.getNode(1, false));
assertEquals("value0", list.getFirst());
assertEquals("value0", list.getLast());
checkNodes();
}
public void testGetNode() {
resetEmpty();
AbstractLinkedList list = (AbstractLinkedList) collection;
// get marker
assertEquals(list.getNode(0, true).previous, list.getNode(0, true).next);
try {
Object obj = list.getNode(0, false);
fail("Expecting IndexOutOfBoundsException.");
} catch (IndexOutOfBoundsException ex) {
// expected
}
list.addAll( Arrays.asList( new String[]{"value1", "value2"}));
checkNodes();
list.addFirst("value0");
checkNodes();
list.removeNode(list.getNode(1, false));
checkNodes();
try {
Object obj = list.getNode(2, false);
fail("Expecting IndexOutOfBoundsException.");
} catch (IndexOutOfBoundsException ex) {
// expected
}
try {
Object obj = list.getNode(-1, false);
fail("Expecting IndexOutOfBoundsException.");
} catch (IndexOutOfBoundsException ex) {
// expected
}
try {
Object obj = list.getNode(3, true);
fail("Expecting IndexOutOfBoundsException.");
} catch (IndexOutOfBoundsException ex) {
// expected
}
}
protected void checkNodes() {
AbstractLinkedList list = (AbstractLinkedList) collection;
for (int i = 0; i < list.size; i++) {
assertEquals(list.getNode(i, false).next, list.getNode(i + 1, true));
if (i < list.size - 1) {
assertEquals(list.getNode(i + 1, false).previous,
list.getNode(i, false));
}
}
}
}

6
src/test/org/apache/commons/collections/list/TestAll.java
View File

@ -1,5 +1,5 @@
/* /*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/test/org/apache/commons/collections/list/TestAll.java,v 1.1 2003/11/16 00:05:44 scolebourne Exp $ * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/test/org/apache/commons/collections/list/TestAll.java,v 1.2 2003/12/11 00:18:06 scolebourne Exp $
* ==================================================================== * ====================================================================
* *
* The Apache Software License, Version 1.1 * The Apache Software License, Version 1.1
@ -65,7 +65,7 @@ import junit.framework.TestSuite;
* Entry point for tests. * Entry point for tests.
* *
* @since Commons Collections 3.0 * @since Commons Collections 3.0
* @version $Revision: 1.1 $ $Date: 2003/11/16 00:05:44 $ * @version $Revision: 1.2 $ $Date: 2003/12/11 00:18:06 $
* *
* @author Stephen Colebourne * @author Stephen Colebourne
*/ */
@ -83,6 +83,8 @@ public class TestAll extends TestCase {
public static Test suite() { public static Test suite() {
TestSuite suite = new TestSuite(); TestSuite suite = new TestSuite();
suite.addTest(TestNodeCachingLinkedList.suite());
suite.addTest(TestFixedSizeList.suite()); suite.addTest(TestFixedSizeList.suite());
suite.addTest(TestPredicatedList.suite()); suite.addTest(TestPredicatedList.suite());
suite.addTest(TestSetUniqueList.suite()); suite.addTest(TestSetUniqueList.suite());

197
src/test/org/apache/commons/collections/list/TestNodeCachingLinkedList.java Normal file
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@ -0,0 +1,197 @@
/*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//collections/src/test/org/apache/commons/collections/list/TestNodeCachingLinkedList.java,v 1.1 2003/12/11 00:18:06 scolebourne Exp $
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowledgement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgement may appear in the software itself,
* if and wherever such third-party acknowledgements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.commons.collections.list;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import junit.framework.Test;
import org.apache.commons.collections.BulkTest;
/**
* Test class for NodeCachingLinkedList, a performance optimised LinkedList.
*
* @version $Revision: 1.1 $ $Date: 2003/12/11 00:18:06 $
*
* @author Jeff Varszegi
* @author Phil Steitz
*/
public class TestNodeCachingLinkedList extends TestAbstractLinkedList {
public TestNodeCachingLinkedList(String testName) {
super(testName);
}
public static void main(String args[]) {
compareSpeed();
String[] testCaseName = { TestNodeCachingLinkedList.class.getName()};
junit.textui.TestRunner.main(testCaseName);
}
public static Test suite() {
return BulkTest.makeSuite(TestNodeCachingLinkedList.class);
}
//-----------------------------------------------------------------------
public List makeEmptyList() {
return new NodeCachingLinkedList();
}
public String getCompatibilityVersion() {
return "3";
}
//-----------------------------------------------------------------------
public void testShrinkCache() {
if (isRemoveSupported() == false || isAddSupported() == false) return;
resetEmpty();
NodeCachingLinkedList list = (NodeCachingLinkedList) collection;
list.addAll( Arrays.asList( new String[]{"1", "2", "3", "4"}));
list.removeAllNodes(); // Will dump all 4 elements into cache
((NodeCachingLinkedList) list).setMaximumCacheSize(2); // shrink cache
list.addAll( Arrays.asList( new String[]{"1", "2", "3", "4"}));
checkNodes();
list.removeNode(list.getNode(0, false)); // no room in cache
list.removeNode(list.getNode(0, false));
list.removeNode(list.getNode(0, false));
checkNodes();
list.addAll( Arrays.asList( new String[]{"1", "2", "3", "4"}));
checkNodes();
}
//-----------------------------------------------------------------------
public static void compareSpeed() {
NodeCachingLinkedList ncll = new NodeCachingLinkedList();
LinkedList ll = new LinkedList();
Object o1 = new Object();
Object o2 = new Object();
int loopCount = 4000000;
long startTime, endTime;
System.out.println("Testing relative execution time of commonly-used methods...");
startTime = System.currentTimeMillis();
for(int x = loopCount; x > 0; x--) {
// unrolled a few times to minimize effect of loop
ll.addFirst(o1);
ll.addLast(o2);
ll.removeFirst();
ll.removeLast();
ll.add(o1);
ll.remove(0);
//
ll.addFirst(o1);
ll.addLast(o2);
ll.removeFirst();
ll.removeLast();
ll.add(o1);
ll.remove(0);
//
ll.addFirst(o1);
ll.addLast(o2);
ll.removeFirst();
ll.removeLast();
ll.add(o1);
ll.remove(0);
}
endTime = System.currentTimeMillis();
System.out.println("Time with LinkedList: " + (endTime - startTime) + " ms");
startTime = System.currentTimeMillis();
for(int x = loopCount; x > 0; x--) {
ncll.addFirst(o1);
ncll.addLast(o2);
ncll.removeFirst();
ncll.removeLast();
ncll.add(o1);
ncll.remove(0);
//
ncll.addFirst(o1);
ncll.addLast(o2);
ncll.removeFirst();
ncll.removeLast();
ncll.add(o1);
ncll.remove(0);
//
ncll.addFirst(o1);
ncll.addLast(o2);
ncll.removeFirst();
ncll.removeLast();
ncll.add(o1);
ncll.remove(0);
}
endTime = System.currentTimeMillis();
System.out.println("Time with NodeCachingLinkedList: " + (endTime - startTime) + " ms");
}
// public void testCreate() throws Exception {
// resetEmpty();
// writeExternalFormToDisk((java.io.Serializable) collection,
// "D:/dev/collections/data/test/NodeCachingLinkedList.emptyCollection.version3.obj");
// resetFull();
// writeExternalFormToDisk((java.io.Serializable) collection,
// "D:/dev/collections/data/test/NodeCachingLinkedList.fullCollection.version3.obj");
// }
}