如何将文件添加到 Jar 文件？

Question

I want to add a series of files previously extracted from other files(already done) to a jar. These files will be overwriting files inside the JAR. What is the most efficient way to do it? I need it to be fast. Thank you

Answer 1

jar -u file.jar file1 file2 file3 ...

Answer 2

jar -uf my.jar file1 file2...
jar -uf my.jar dir/

or mixed

jar -uf my.jar file dir/

Answer 3

A JAR file is a ZIP file, remember.

Just use some ZIP library.

Answer 4

 zip file.jar file1 file2 file3 

在 Mac Os 10.7.5 中为我工作

Answer 5

//Add a file in jar in a particular folder
jar uvf <jar file name> <file to be added> <folder name inside jar>

Answer 6

Extending the existing answers, I find the -C jar option very useful when adding files that are on their own folder and you flatten their path out.

$ jar uf jar-file -C /path/to/my_jars/ this_useful.jar

---

You will end up having this_useful.jar right in the JAR's root:

$ jar tf jar-file | grep this_useful.jar
this_useful.jar

Answer 7

If someone needs a programmatically answer, here it is.

private static void createJar(File source, JarOutputStream target) {
    createJar(source, source, target);
}

private static void createJar(File source, File baseDir, JarOutputStream target) {
    BufferedInputStream in = null;

    try {
        if (!source.exists()) {
            throw new IOException("Source directory is empty");
        }
        if (source.isDirectory()) {
            // For Jar entries, all path separates should be '/'(OS independent)
            String name = source.getPath().replace("\\", "/");
            if (!name.isEmpty()) {
                if (!name.endsWith("/")) {
                    name += "/";
                }
                JarEntry entry = new JarEntry(name);
                entry.setTime(source.lastModified());
                target.putNextEntry(entry);
                target.closeEntry();
            }
            for (File nestedFile: source.listFiles()) {
                createJar(nestedFile, baseDir, target);
            }
            return;
        }

        String entryName = baseDir.toPath().relativize(source.toPath()).toFile().getPath().replace("\\", "/");
        JarEntry entry = new JarEntry(entryName);
        entry.setTime(source.lastModified());
        target.putNextEntry(entry); in = new BufferedInputStream(new FileInputStream(source));

        byte[] buffer = new byte[1024];
        while (true) {
            int count = in .read(buffer);
            if (count == -1)
                break;
            target.write(buffer, 0, count);
        }
        target.closeEntry();
    } catch (Exception ignored) {

    } finally {
        if ( in != null) {
            try { in .close();
            } catch (Exception ignored) {
                throw new RuntimeException(ignored);
            }
        }
    }
}

Answer 8

Just to add to the existing answers, there is at least one special case: so-called executable JAR files. If you add another JAR file as a dependency -- whether you use jar or zip -- it will complain that the embedded file is compressed:

Caused by: java.lang.IllegalStateException: Unable to open nested entry 'BOOT-INF/lib/file.jar'. It has been compressed and nested jar files must be stored without compression. Please check the mechanism used to create your executable jar file

The solution to this is to use the 0 option to jar:

jar uvf0 myfile.jar BOOT-INF/lib/file.jar

You don't need this for normal class files.

Answer 9

String cmd = "jar uvf " + "jarName" + " " + "Filename";
System.out.println(cmd);
try {
Process p = Runtime.getRuntime().exec(cmd);
}
catch (Exception ex) {
}

Answer 10

Here is another example of copying directory content to JAR file.

/**
 * Copy source directory content to selected JAR file folder.
 * @param directory
 * @param jarFile
 * @param jarFolder
 * @throws Exception
 */
protected void copyDirectoryToJar(String directory, String jarFile, String jarFolder)
        throws Exception {
    
    // Initialize local variables.
    FileSystem destinationJarFileSystem = null;
    Exception exception = null;
    try {
        // Get source path.
        final Path sourcePath = Paths.get(directory);
        
        // Get destination JAR file system and destination path inside the JAR file.
        final URI uri = URI.create("jar:file:/" + jarFile.replace(File.separatorChar, '/'));
        final Map<String, String> environment = Map.of("create", "true");
        destinationJarFileSystem = FileSystems.newFileSystem(uri, environment);
        final Path destinationPath = destinationJarFileSystem.getPath(jarFolder);

        // Copy source directory into target JAR file.
        copyFromDirToJar(sourcePath, destinationPath, destinationJarFileSystem);
    }
    catch (Exception e) {
        exception = e;
    }
    finally {
        // Close JAR file systems.
        try {
            if (destinationJarFileSystem != null) {
                destinationJarFileSystem.close();
            }
        }
        catch (Exception e) {
            if (exception == null) {
                exception = e;
            }
        }
    }
    
    // Throw exception.
    if (exception != null) {
        throw exception;
    }   
}

/* Recursively copy the source sub directories and files to target JAR file system.
 * @param sourcePath
 * @param destinationPath
 * @param destinationFileSystem
 */
private static void copyFromDirToJar(Path sourcePath, Path destinationPath, FileSystem destinationFileSystem)
        throws Exception {
    
    // Create destination directory if it doesn't exist.
    if (!Files.exists(destinationPath)) {
        Files.createDirectories(destinationPath);
    }
    
    // If the source and destination paths designate files, copy the source
    // file directly to the destination file.
    if (Files.isRegularFile(sourcePath) && Files.isRegularFile(destinationPath)) {
        Files.copy(sourcePath, destinationPath, StandardCopyOption.REPLACE_EXISTING);
    }
    
    // List sub directories in the source path.
    Exception [] exception = new Exception [] {null};
    Files.list(sourcePath).forEachOrdered(sourceSubPath -> {
        try {
            Path fileOrFolder = sourceSubPath.getFileName();
            Path destinationSubPath = destinationFileSystem.getPath(destinationPath.toString(), fileOrFolder.toString());
            
            // Copy sub directories recursively or copy a single file.
            if (Files.isDirectory(sourceSubPath)) {
                copyFromDirToJar(sourceSubPath, destinationSubPath, destinationFileSystem);
            }
            else {
                Files.copy(sourceSubPath, destinationSubPath, StandardCopyOption.REPLACE_EXISTING);
            }
        }
        catch (Exception e) {
            exception[0] = e;
        }
    });
    
    // Throw exception.
    if (exception[0] != null) {
        throw exception[0];
    }
}