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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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package org.apache.commons.io.comparator;
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import java.io.Serializable;
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import java.util.Comparator;
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import org.apache.commons.io.FileUtils;
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* Compare the <b>length/size</b> of two files for order (see
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* {@link File#length()} and {@link FileUtils#sizeOfDirectory(File)}).
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* This comparator can be used to sort lists or arrays of files
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* by their length/size.
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* Example of sorting a list of files using the
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* {@link #SIZE_COMPARATOR} singleton instance:
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* List<File> list = ...
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* Collections.sort(list, LengthFileComparator.LENGTH_COMPARATOR);
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* Example of doing a <i>reverse</i> sort of an array of files using the
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* {@link #SIZE_REVERSE} singleton instance:
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* Arrays.sort(array, LengthFileComparator.LENGTH_REVERSE);
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* <strong>N.B.</strong> Directories are treated as <b>zero size</b> unless
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* <code>sumDirectoryContents</code> is <code>true</code>.
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* @version $Revision: 609243 $ $Date: 2008-01-06 00:30:42 +0000 (Sun, 06 Jan 2008) $
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* @since Commons IO 1.4
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public class SizeFileComparator implements Comparator, Serializable {
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/** Size comparator instance - directories are treated as zero size */
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public static final Comparator SIZE_COMPARATOR = new SizeFileComparator();
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/** Reverse size comparator instance - directories are treated as zero size */
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public static final Comparator SIZE_REVERSE = new ReverseComparator(SIZE_COMPARATOR);
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* Size comparator instance which sums the size of a directory's contents
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* using {@link FileUtils#sizeOfDirectory(File)}
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public static final Comparator SIZE_SUMDIR_COMPARATOR = new SizeFileComparator(true);
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* Reverse size comparator instance which sums the size of a directory's contents
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* using {@link FileUtils#sizeOfDirectory(File)}
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public static final Comparator SIZE_SUMDIR_REVERSE = new ReverseComparator(SIZE_SUMDIR_COMPARATOR);
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/** Whether the sum of the directory's contents should be calculated. */
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private final boolean sumDirectoryContents;
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* Construct a file size comparator instance (directories treated as zero size).
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public SizeFileComparator() {
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this.sumDirectoryContents = false;
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* Construct a file size comparator instance specifying whether the size of
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* the directory contents should be aggregated.
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* If the <code>sumDirectoryContents</code> is <code>true</code> The size of
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* directories is calculated using {@link FileUtils#sizeOfDirectory(File)}.
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* @param sumDirectoryContents <code>true</code> if the sum of the directoryies contents
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* should be calculated, otherwise <code>false</code> if directories should be treated
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* as size zero (see {@link FileUtils#sizeOfDirectory(File)}).
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public SizeFileComparator(boolean sumDirectoryContents) {
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this.sumDirectoryContents = sumDirectoryContents;
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* Compare the length of two files.
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* @param obj1 The first file to compare
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* @param obj2 The second file to compare
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* @return a negative value if the first file's length
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* is less than the second, zero if the lengths are the
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* same and a positive value if the first files length
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* is greater than the second file.
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public int compare(Object obj1, Object obj2) {
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File file1 = (File)obj1;
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File file2 = (File)obj2;
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if (file1.isDirectory()) {
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size1 = sumDirectoryContents && file1.exists() ? FileUtils.sizeOfDirectory(file1) : 0;
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size1 = file1.length();
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if (file2.isDirectory()) {
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size2 = sumDirectoryContents && file2.exists() ? FileUtils.sizeOfDirectory(file2) : 0;
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size2 = file2.length();
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long result = size1 - size2;
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} else if (result > 0) {
added
removed
src/java/org/apache/commons/io/comparator/SizeFileComparator.java
