1 /*
2 * This file is part of dependency-check-core.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *
16 * Copyright (c) 2012 Jeremy Long. All Rights Reserved.
17 */
18 package org.owasp.dependencycheck.utils;
19
20 import org.apache.commons.io.FilenameUtils;
21 import org.slf4j.Logger;
22 import org.slf4j.LoggerFactory;
23
24 import java.io.File;
25 import java.io.IOException;
26 import java.util.UUID;
27
28 /**
29 * A collection of utilities for processing information about files.
30 *
31 * @author Jeremy Long
32 */
33 public final class FileUtils {
34
35 /**
36 * The logger.
37 */
38 private static final Logger LOGGER = LoggerFactory.getLogger(FileUtils.class);
39 /**
40 * Bit bucket for non-Windows systems
41 */
42 private static final String BIT_BUCKET_UNIX = "/dev/null";
43
44 /**
45 * Bit bucket for Windows systems (yes, only one 'L')
46 */
47 private static final String BIT_BUCKET_WIN = "NUL";
48
49 /**
50 * Private constructor for a utility class.
51 */
52 private FileUtils() {
53 }
54
55 /**
56 * Returns the (lowercase) file extension for a specified file.
57 *
58 * @param fileName the file name to retrieve the file extension from.
59 * @return the file extension.
60 */
61 public static String getFileExtension(String fileName) {
62 final String fileExt = FilenameUtils.getExtension(fileName);
63 return null == fileExt || fileExt.isEmpty() ? null : fileExt.toLowerCase();
64 }
65
66 /**
67 * Deletes a file. If the File is a directory it will recursively delete the contents.
68 *
69 * @param file the File to delete
70 * @return true if the file was deleted successfully, otherwise false
71 */
72 public static boolean delete(File file) {
73 final boolean success = org.apache.commons.io.FileUtils.deleteQuietly(file);
74 if (!success) {
75 LOGGER.debug("Failed to delete file: {}; attempting to delete on exit.", file.getPath());
76 file.deleteOnExit();
77 }
78 return success;
79 }
80
81 /**
82 * Generates a new temporary file name that is guaranteed to be unique.
83 *
84 * @param prefix the prefix for the file name to generate
85 * @param extension the extension of the generated file name
86 * @return a temporary File
87 * @throws java.io.IOException thrown if the temporary folder could not be created
88 */
89 public static File getTempFile(String prefix, String extension) throws IOException {
90 final File dir = Settings.getTempDirectory();
91 final String tempFileName = String.format("%s%s.%s", prefix, UUID.randomUUID().toString(), extension);
92 final File tempFile = new File(dir, tempFileName);
93 if (tempFile.exists()) {
94 return getTempFile(prefix, extension);
95 }
96 return tempFile;
97 }
98
99 /**
100 * Return the bit bucket for the OS. '/dev/null' for Unix and 'NUL' for Windows
101 *
102 * @return a String containing the bit bucket
103 */
104 public static String getBitBucket() {
105 if (System.getProperty("os.name").startsWith("Windows")) {
106 return BIT_BUCKET_WIN;
107 } else {
108 return BIT_BUCKET_UNIX;
109 }
110 }
111 }