Add a BZip2Utils class matching GZipUtils. Submitted by Jukka Zitting. COMPRESS-78
git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@789607 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index a503b61..7ecb3ed 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -26,6 +26,10 @@
<action issue="COMPRESS-81" type="fix" date="2009-06-30">
TarOutputStream can leave garbage at the end of the archive
</action>
+ <action issue="COMPRESS-78" type="add" date="2009-06-30"
+ due-to="Jukka Zitting">
+ Add a BZip2Utils class modelled after GZipUtils
+ </action>
</release>
<release version="1.0" date="2009-05-21" description="First Public Release">
<action dev="all" type="add" date="2009-05-21">
diff --git a/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2Utils.java b/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2Utils.java
new file mode 100644
index 0000000..d2b97fd
--- /dev/null
+++ b/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2Utils.java
@@ -0,0 +1,112 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.commons.compress.compressors.bzip2;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Utility code for the BZip2 compression format.
+ * @ThreadSafe
+ * @since Commons Compress 1.1
+ */
+public abstract class BZip2Utils {
+
+ /**
+ * Map from common filename suffixes of bzip2ed files to the corresponding
+ * suffixes of uncompressed files. For example: from ".tbz2" to ".tar".
+ * <p>
+ * This map also contains bzip2-specific suffixes like ".bz2". These
+ * suffixes are mapped to the empty string, as they should simply be
+ * removed from the filename when the file is uncompressed.
+ */
+ private static final Map uncompressSuffix = new HashMap();
+
+ static {
+ uncompressSuffix.put(".tbz2", ".tar");
+ uncompressSuffix.put(".tbz", ".tar");
+ uncompressSuffix.put(".bz2", "");
+ uncompressSuffix.put(".bz", "");
+ }
+ // N.B. if any shorter or longer keys are added, ensure the for loop limits are changed
+
+ /** Private constructor to prevent instantiation of this utility class. */
+ private BZip2Utils() {
+ }
+
+ /**
+ * Detects common bzip2 suffixes in the given filename.
+ *
+ * @param filename name of a file
+ * @return <code>true</code> if the filename has a common bzip2 suffix,
+ * <code>false</code> otherwise
+ */
+ public static boolean isCompressedFilename(String filename) {
+ String lower = filename.toLowerCase();
+ int n = lower.length();
+ // Shortest suffix is three letters (.bz), longest is five (.tbz2)
+ for (int i = 3; i <= 5 && i < n; i++) {
+ if (uncompressSuffix.containsKey(lower.substring(n - i))) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Maps the given name of a bzip2-compressed file to the name that the
+ * file should have after uncompression. Commonly used file type specific
+ * suffixes like ".tbz" or ".tbz2" are automatically detected and
+ * correctly mapped. For example the name "package.tbz2" is mapped to
+ * "package.tar". And any filenames with the generic ".bz2" suffix
+ * (or any other generic bzip2 suffix) is mapped to a name without that
+ * suffix. If no bzip2 suffix is detected, then the filename is returned
+ * unmapped.
+ *
+ * @param filename name of a file
+ * @return name of the corresponding uncompressed file
+ */
+ public static String getUncompressedFilename(String filename) {
+ String lower = filename.toLowerCase();
+ int n = lower.length();
+ // Shortest suffix is three letters (.bz), longest is five (.tbz2)
+ for (int i = 3; i <= 5 && i < n; i++) {
+ Object suffix = uncompressSuffix.get(lower.substring(n - i));
+ if (suffix != null) {
+ return filename.substring(0, n - i) + suffix;
+ }
+ }
+ return filename;
+ }
+
+ /**
+ * Maps the given filename to the name that the file should have after
+ * compression with bzip2. Currently this method simply appends the suffix
+ * ".bz2" to the filename based on the standard behaviour of the "bzip2"
+ * program, but a future version may implement a more complex mapping if
+ * a new widely used naming pattern emerges.
+ *
+ * @param filename name of a file
+ * @return name of the corresponding compressed file
+ */
+ public static String getCompressedFilename(String filename) {
+ return filename + ".bz2";
+ }
+
+}
diff --git a/src/test/java/org/apache/commons/compress/compressors/BZip2UtilsTestCase.java b/src/test/java/org/apache/commons/compress/compressors/BZip2UtilsTestCase.java
new file mode 100644
index 0000000..9905ee6
--- /dev/null
+++ b/src/test/java/org/apache/commons/compress/compressors/BZip2UtilsTestCase.java
@@ -0,0 +1,75 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.commons.compress.compressors;
+
+import org.apache.commons.compress.compressors.bzip2.BZip2Utils;
+
+import junit.framework.TestCase;
+
+public class BZip2UtilsTestCase extends TestCase {
+
+ public void testIsCompressedFilename() {
+ assertFalse(BZip2Utils.isCompressedFilename(""));
+ assertFalse(BZip2Utils.isCompressedFilename(".gz"));
+
+ assertTrue(BZip2Utils.isCompressedFilename("x.tbz2"));
+ assertTrue(BZip2Utils.isCompressedFilename("x.tbz"));
+ assertTrue(BZip2Utils.isCompressedFilename("x.bz2"));
+ assertTrue(BZip2Utils.isCompressedFilename("x.bz"));
+
+ assertFalse(BZip2Utils.isCompressedFilename("xbz2"));
+ assertFalse(BZip2Utils.isCompressedFilename("xbz"));
+
+ assertTrue(BZip2Utils.isCompressedFilename("x.TBZ2"));
+ assertTrue(BZip2Utils.isCompressedFilename("x.Tbz2"));
+ assertTrue(BZip2Utils.isCompressedFilename("x.tbZ2"));
+
+ assertFalse(BZip2Utils.isCompressedFilename("x.bz "));
+ assertFalse(BZip2Utils.isCompressedFilename("x.tbz\n"));
+ assertFalse(BZip2Utils.isCompressedFilename("x.tbz2.y"));
+ }
+
+ public void testGetUncompressedFilename() {
+ assertEquals("", BZip2Utils.getUncompressedFilename(""));
+ assertEquals(".bz2", BZip2Utils.getUncompressedFilename(".bz2"));
+
+ assertEquals("x.tar", BZip2Utils.getUncompressedFilename("x.tbz2"));
+ assertEquals("x.tar", BZip2Utils.getUncompressedFilename("x.tbz"));
+ assertEquals("x", BZip2Utils.getUncompressedFilename("x.bz2"));
+ assertEquals("x", BZip2Utils.getUncompressedFilename("x.bz"));
+
+ assertEquals("x.tar", BZip2Utils.getUncompressedFilename("x.TBZ2"));
+ assertEquals("X.tar", BZip2Utils.getUncompressedFilename("X.Tbz2"));
+ assertEquals("X.tar", BZip2Utils.getUncompressedFilename("X.tbZ2"));
+
+ assertEquals("x.bz ", BZip2Utils.getUncompressedFilename("x.bz "));
+ assertEquals("x.tbz\n", BZip2Utils.getUncompressedFilename("x.tbz\n"));
+ assertEquals("x.tbz2.y", BZip2Utils.getUncompressedFilename("x.tbz2.y"));
+ }
+
+ public void testGetCompressedFilename() {
+ assertEquals(".bz2", BZip2Utils.getCompressedFilename(""));
+ assertEquals(" .bz2", BZip2Utils.getCompressedFilename(" "));
+ assertEquals("x.bz2", BZip2Utils.getCompressedFilename("x"));
+ assertEquals("X.bz2", BZip2Utils.getCompressedFilename("X"));
+ assertEquals("x.tar.bz2", BZip2Utils.getCompressedFilename("x.tar"));
+ assertEquals("x.TAR.bz2", BZip2Utils.getCompressedFilename("x.TAR"));
+ }
+
+}