Java 解壓RAR5

RAR5加密演算法並未公佈，所以很多開源工具包都只支援rar4，在解壓rar5格式時，會報出不支援rar5格式的錯誤，比如常用的junara

經過仔細的翻閱Google，找到了解決方案

1.新增pom檔案依賴

 <dependency>
            <groupId>com.github.axet</groupId>
            <artifactId>java-unrar</artifactId>
            <version>1.7.0-8</version>
        </dependency>
        <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>
 

2.例子

package rar5;
 
import java.io.IOException;
import java.io.RandomAccessFile;
 
import net.sf.sevenzipjbinding.IInArchive;
import net.sf.sevenzipjbinding.SevenZip;
import net.sf.sevenzipjbinding.impl.RandomAccessFileInStream;
 
public class RAR5Test {
	public static void main(String[] args) throws IOException {
	    String rarDir = "D:\\rar5.rar";
	    String outDir = "D:\\rar5";
	    IInArchive archive;
            RandomAccessFile randomAccessFile;
            // 第一個引數是需要解壓的壓縮包路徑，第二個引數參考JdkAPI文件的RandomAccessFile
            //r代表以只讀的方式開啟文字，也就意味著不能用write來操作檔案
            randomAccessFile = new RandomAccessFile(rarDir, "r");
            archive = SevenZip.openInArchive(null, // null - autodetect
                    new RandomAccessFileInStream(randomAccessFile));
            int[] in = new int[archive.getNumberOfItems()];
            for (int i = 0; i < in.length; i++) {
                in[i] = i;
            }
            archive.extract(in, false, new ExtractCallback(archive,unRarDir.getAbsolutePath() + "/"));
            archive.close();
            randomAccessFile.close();
 
	}
}
 

3.編寫回調ExtractCallback

public class ExtractCallback implements IArchiveExtractCallback {

    private int index;
    private IInArchive inArchive;
    private String ourDir;

    public ExtractCallback(IInArchive inArchive, String ourDir) {
        this.inArchive = inArchive;
        this.ourDir = ourDir;
    }

    @Override
    public void setCompleted(long arg0) throws SevenZipException {
    }

    @Override
    public void setTotal(long arg0) throws SevenZipException {
    }

    @Override
    public ISequentialOutStream getStream(int index, ExtractAskMode extractAskMode) throws SevenZipException {
        this.index = index;
        final String path = (String) inArchive.getProperty(index, PropID.PATH);
        final boolean isFolder = (boolean) inArchive.getProperty(index, PropID.IS_FOLDER);
        return data -> {
            try {
                if (!isFolder) {
                    File file = new File(ourDir + path);
                    save2File(file, data);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return data.length;
        };
    }

    @Override
    public void prepareOperation(ExtractAskMode arg0) throws SevenZipException {
    }

    @Override
    public void setOperationResult(ExtractOperationResult extractOperationResult) throws SevenZipException {

    }

    public static boolean save2File(File file, byte[] msg) {
        OutputStream fos = null;
        try {
            File parent = file.getParentFile();
            if ((!parent.exists()) && (!parent.mkdirs())) {
                return false;
            }
            fos = new FileOutputStream(file, true);
            fos.write(msg);
            fos.flush();
            return true;
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return false;
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        } finally {
            try {
                fos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}