Extract RPM Files with redline

Extractor.java

package rpm;

import org.freecompany.redline.ReadableChannelWrapper;
import org.freecompany.redline.Scanner;
import org.freecompany.redline.header.Format;
import org.freecompany.redline.payload.CpioHeader;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.nio.channels.Channels;
import java.nio.channels.WritableByteChannel;
import java.util.zip.GZIPInputStream;

public class Extractor {
    public static File FILE = new File("test1.rpm");
    public static File target = new File("target", "test1");

    public static void main(String[] args) throws Exception {
        makeDir(target);
        System.out.println("FILE = " + FILE);
        InputStream fios = new FileInputStream( FILE.toString() );
        ReadableChannelWrapper in = new ReadableChannelWrapper( Channels.newChannel(fios));
        Format format = new Scanner().run( in);
        System.out.println( format);
        InputStream uncompressed = new GZIPInputStream( fios );
        in = new ReadableChannelWrapper( Channels.newChannel( uncompressed));
        CpioHeader header;
        int total = 0;
        do {
            header = new CpioHeader();
            total = header.read( in, total);
            if (header.getType() == CpioHeader.DIR) {
                makeDir(new File(target, header.getName()));
            }
            else if (header.getType() == CpioHeader.FILE) {
                File file = new File(target, header.getName());
                File parent = file.getAbsoluteFile().getParentFile();
                if (!parent.exists()) {
                    makeDir(parent);
                }
                FileOutputStream str = new FileOutputStream(file);
                WritableByteChannel writableByteChannel = Channels.newChannel(str);
                try {
                    header.write(writableByteChannel, header.getFileSize());
                } finally {
                    writableByteChannel.close();
                }
            }
            System.out.println( header);
            final int skip = header.getFileSize();
            if ( uncompressed.skip( skip) != skip) throw new RuntimeException( "Skip failed.");
            total += header.getFileSize();
        } while ( !header.isLast());

    }

    private static void makeDir(File file) {
        if (!file.exists() && !file.mkdirs()) {
            throw new IllegalStateException("Failed to create directory");
        }
    }
}

The actual extraction of data is not done in this example; line 53 can be written like

// Determine size of file
final int filesize = header.getFileSize();

// Read file data into byte array
byte[] content = org.apache.commons.io.IOUtils.toByteArray(uncompressed, filesize);

I have tried the code for extracting my custom created .rpm file, although it's extracted but the size is not correct
Appreciate a lot if any guidance here!

Can you please share the exact code to extract the complete rpm file.

Tanweer

I tried above code, it extract the rpm file but it is creating 1KB files and content of the file is like below

070701004dc0ac000081ed0000000000000000000000015b1786de00037600000000fd0000000000000000000000000000000e00000000./