java第三方库创建rar4文件

您可以使用Apache Commons Compress库来创建RAR4文件。以下是一个简单的示例代码：

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.commons.compress.archivers.ArchiveEntry;
import org.apache.commons.compress.archivers.ArchiveOutputStream;
import org.apache.commons.compress.archivers.rar.RarArchiveEntry;
import org.apache.commons.compress.archivers.rar.RarArchiveOutputStream;
import org.apache.commons.compress.utils.IOUtils;

public class CreateRar {

    public static void main(String[] args) throws IOException {
        String sourceDir = "path/to/source/dir";
        String destFile = "path/to/destination/file.rar";
        
        // create output stream
        FileOutputStream fos = new FileOutputStream(new File(destFile));
        ArchiveOutputStream aos = new RarArchiveOutputStream(fos);
        
        // iterate through source directory
        File dir = new File(sourceDir);
        for (File file : dir.listFiles()) {
            // create archive entry
            ArchiveEntry entry = new RarArchiveEntry(file.getName());
            entry.setSize(file.length());
            
            // add entry to archive
            aos.putArchiveEntry(entry);
            
            // write file content to archive
            IOUtils.copy(file, aos);
            
            // close current entry
            aos.closeArchiveEntry();
        }
        
        // close output stream
        aos.finish();
        fos.close();
    }
}

请注意，您需要在项目中添加Apache Commons Compress库的依赖关系。