使用java提取.rar文件

Question

我正在尋找一種使用 Java 解壓縮.rar文件的方法，無論我在哪里搜索，我都會以相同的工具 - JavaUnRar 。 我一直在研究用這個解壓.rar文件，但我似乎找到的所有方法都非常冗長和笨拙，就像這個例子一樣

我目前能夠在 20 行或更少的代碼中提取.tar 、 .tar.gz 、 .zip和.jar文件，所以必須有更簡單的方法來提取.rar文件，有人知道嗎？

如果它對任何人有幫助，這就是我用來提取.zip和.jar文件的代碼，它適用於兩者

 public void getZipFiles(String zipFile, String destFolder) throws IOException {
    BufferedOutputStream dest = null;
    ZipInputStream zis = new ZipInputStream(
                                       new BufferedInputStream(
                                             new FileInputStream(zipFile)));
    ZipEntry entry;
    while (( entry = zis.getNextEntry() ) != null) {
        System.out.println( "Extracting: " + entry.getName() );
        int count;
        byte data[] = new byte[BUFFER];

        if (entry.isDirectory()) {
            new File( destFolder + "/" + entry.getName() ).mkdirs();
            continue;
        } else {
            int di = entry.getName().lastIndexOf( '/' );
            if (di != -1) {
                new File( destFolder + "/" + entry.getName()
                                             .substring( 0, di ) ).mkdirs();
            }
        }
        FileOutputStream fos = new FileOutputStream( destFolder + "/"
                                                     + entry.getName() );
        dest = new BufferedOutputStream( fos );
        while (( count = zis.read( data ) ) != -1) 
            dest.write( data, 0, count );
        dest.flush();
        dest.close();
    }
}

Answer 1

您可以提取.gz 、 .zip 、 .jar文件，因為它們使用了 Java SDK 內置的多種壓縮算法。

RAR格式的情況有點不同。 RAR 是專有的存檔文件格式。 RAR 許可證不允許將其包含到 Java SDK 等軟件開發工具中。

解壓縮文件的最佳方法是使用 3rd 方庫，例如 junrar 。

您可以在 SO question RAR archives with java中找到對其他 Java RAR 庫的一些引用。 還有一個問題How to compress text file to rar format using java program解釋了更多不同的解決方法（例如使用Runtime ）。

Answer 2

你可以使用庫junrar

<dependency>
   <groupId>com.github.junrar</groupId>
   <artifactId>junrar</artifactId>
   <version>0.7</version>
</dependency>

代碼示例：

            File f = new File(filename);
            Archive archive = new Archive(f);
            archive.getMainHeader().print();
            FileHeader fh = archive.nextFileHeader();
            while(fh!=null){        
                    File fileEntry = new File(fh.getFileNameString().trim());
                    System.out.println(fileEntry.getAbsolutePath());
                    FileOutputStream os = new FileOutputStream(fileEntry);
                    archive.extractFile(fh, os);
                    os.close();
                    fh=archive.nextFileHeader();
            }

Answer 3

你可以使用http://sevenzipjbind.sourceforge.net/index.html

除了支持大量存檔格式外，16.02-2.01 版還全面支持 RAR5 提取：

• 密碼保護檔案
• 帶有加密標題的存檔
• 檔案分成幾卷

搖籃

implementation 'net.sf.sevenzipjbinding:sevenzipjbinding:16.02-2.01'
implementation 'net.sf.sevenzipjbinding:sevenzipjbinding-all-platforms:16.02-2.01'

或行家

<dependency>
    <groupId>net.sf.sevenzipjbinding</groupId>
    <artifactId>sevenzipjbinding</artifactId>
    <version>16.02-2.01</version>
</dependency>
<dependency>
    <groupId>net.sf.sevenzipjbinding</groupId>
    <artifactId>sevenzipjbinding-all-platforms</artifactId>
    <version>16.02-2.01</version>
</dependency>

和代碼示例

import net.sf.sevenzipjbinding.ExtractOperationResult;
import net.sf.sevenzipjbinding.IInArchive;
import net.sf.sevenzipjbinding.SevenZip;
import net.sf.sevenzipjbinding.impl.RandomAccessFileInStream;
import net.sf.sevenzipjbinding.simple.ISimpleInArchiveItem;

import java.io.*;
import java.util.HashMap;
import java.util.Map;

/**
 * Responsible for unpacking archives with the RAR extension.
 * Support Rar4, Rar4 with password, Rar5, Rar5 with password.
 * Determines the type of archive itself.
 */
public class RarExtractor {

    /**
     * Extracts files from archive. Archive can be encrypted with password
     *
     * @param filePath path to .rar file
     * @param password string password for archive
     * @return map of extracted file with file name
     * @throws IOException
     */
    public Map<InputStream, String> extract(String filePath, String password) throws IOException {
        Map<InputStream, String> extractedMap = new HashMap<>();

        RandomAccessFile randomAccessFile = new RandomAccessFile(filePath, "r");
        RandomAccessFileInStream randomAccessFileStream = new RandomAccessFileInStream(randomAccessFile);
        IInArchive inArchive = SevenZip.openInArchive(null, randomAccessFileStream);

        for (ISimpleInArchiveItem item : inArchive.getSimpleInterface().getArchiveItems()) {
            if (!item.isFolder()) {
                ExtractOperationResult result = item.extractSlow(data -> {
                    extractedMap.put(new BufferedInputStream(new ByteArrayInputStream(data)), item.getPath());

                    return data.length;
                }, password);

                if (result != ExtractOperationResult.OK) {
                    throw new RuntimeException(
                            String.format("Error extracting archive. Extracting error: %s", result));
                }
            }
        }

        return extractedMap;
    }
}

PS @BorisBrodski https://github.com/borisbrodski祝你 40 歲生日快樂。 希望你有一個偉大的慶祝活動。 感謝您的工作！

Answer 4

您可以簡單地將此 Maven 依賴項添加到您的代碼中：

<dependency>
    <groupId>com.github.junrar</groupId>
    <artifactId>junrar</artifactId>
    <version>0.7</version>
</dependency>

然后使用此代碼提取 rar 文件：

        File rar = new File("path_to_rar_file.rar");
    File tmpDir = File.createTempFile("bip.",".unrar");
    if(!(tmpDir.delete())){
        throw new IOException("Could not delete temp file: " + tmpDir.getAbsolutePath());
    }
    if(!(tmpDir.mkdir())){
        throw new IOException("Could not create temp directory: " + tmpDir.getAbsolutePath());
    }
    System.out.println("tmpDir="+tmpDir.getAbsolutePath());
    ExtractArchive extractArchive = new ExtractArchive();
    extractArchive.extractArchive(rar, tmpDir);
    System.out.println("finished.");

Answer 5

如果您有輸入流，此方法有助於將文件從 rar(RAR5) 文件流中提取到流中。 在我的例子中，我正在處理來自電子郵件的 MimeBodyPart。

來自@Alexey Bril 的示例對我不起作用。

依賴是一樣的

搖籃

implementation 'net.sf.sevenzipjbinding:sevenzipjbinding:16.02-2.01'
implementation 'net.sf.sevenzipjbinding:sevenzipjbinding-all-platforms:16.02-2.01'

行家

<dependency>
    <groupId>net.sf.sevenzipjbinding</groupId>
    <artifactId>sevenzipjbinding</artifactId>
    <version>16.02-2.01</version>
</dependency>
<dependency>
    <groupId>net.sf.sevenzipjbinding</groupId>
    <artifactId>sevenzipjbinding-all-platforms</artifactId>
    <version>16.02-2.01</version>
</dependency>  

代碼

private List<InputStream> getInputStreamsFromRar5InputStream(InputStream is) throws IOException {

    List<InputStream> inputStreams = new ArrayList<>();
    
    File tempFile = File.createTempFile("tempRarArchive-", ".rar", null);

    try (FileOutputStream fos = new FileOutputStream(tempFile)) {
        fos.write(is.readAllBytes());
        fos.flush();
        try (RandomAccessFile raf = new RandomAccessFile(tempFile, "r")) {// open for reading
            try (IInArchive inArchive = SevenZip.openInArchive(null, // autodetect archive type
                    new RandomAccessFileInStream(raf))) {
                // Getting simple interface of the archive inArchive
                ISimpleInArchive simpleInArchive = inArchive.getSimpleInterface();

                for (ISimpleInArchiveItem item : simpleInArchive.getArchiveItems()) {
                    if (!item.isFolder()) {
                        ExtractOperationResult result;
                        final InputStream[] IS = new InputStream[1];

                        final Integer[] sizeArray = new Integer[1];
                        result = item.extractSlow(new ISequentialOutStream() {
                            /**
                             * @param bytes of extracted data
                             * @return size of extracted data
                             */
                            @Override
                            public int write(byte[] bytes) {
                                InputStream is = new ByteArrayInputStream(bytes);
                                sizeArray[0] = bytes.length;
                                IS[0] = new BufferedInputStream(is); // Data to write to file
                                return sizeArray[0];
                            }
                        });

                        if (result == ExtractOperationResult.OK) {
                            inputStreams.add(IS[0]);
                        } else {
                            log.error("Error extracting item: " + result);
                        }
                    }
                }
            }
        }
        
    } finally {
        tempFile.delete();
    }

    return inputStreams;

}