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Diffstat (limited to 'subsonic-main/src/main/java/net/sourceforge/subsonic/util/BoundedList.java')
-rw-r--r-- | subsonic-main/src/main/java/net/sourceforge/subsonic/util/BoundedList.java | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/subsonic-main/src/main/java/net/sourceforge/subsonic/util/BoundedList.java b/subsonic-main/src/main/java/net/sourceforge/subsonic/util/BoundedList.java new file mode 100644 index 00000000..fb240d5f --- /dev/null +++ b/subsonic-main/src/main/java/net/sourceforge/subsonic/util/BoundedList.java @@ -0,0 +1,71 @@ +/* + This file is part of Subsonic. + + Subsonic is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + Subsonic 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with Subsonic. If not, see <http://www.gnu.org/licenses/>. + + Copyright 2009 (C) Sindre Mehus + */ +package net.sourceforge.subsonic.util; + +import java.util.*; + +/** + * Simple implementation of a bounded list. If the maximum size is reached, adding a new element will + * remove the first element in the list. + * + * @author Sindre Mehus + * @version $Revision: 1.1 $ $Date: 2005/05/09 20:01:25 $ + */ +public class BoundedList<E> extends LinkedList<E> { + private int maxSize; + + /** + * Creates a new bounded list with the given maximum size. + * @param maxSize The maximum number of elements the list may hold. + */ + public BoundedList(int maxSize) { + this.maxSize = maxSize; + } + + /** + * Adds an element to the tail of the list. If the list is full, the first element is removed. + * @param e The element to add. + * @return Always <code>true</code>. + */ + public boolean add(E e) { + if (isFull()) { + removeFirst(); + } + return super.add(e); + } + + /** + * Adds an element to the head of list. If the list is full, the last element is removed. + * @param e The element to add. + */ + public void addFirst(E e) { + if (isFull()) { + removeLast(); + } + super.addFirst(e); + } + + /** + * Returns whether the list if full. + * @return Whether the list is full. + */ + private boolean isFull() { + return size() == maxSize; + } +} |