Question

I have tried multiple ways to create this zip file in Java/Groovy. The first couple methods I attempted, from various blogs/postings, resulted in corrupt zip files which could not be opened. So, I tried this one (below) which looked fairly promising. The sysouts report valid file paths being passed to the FileInputStream. I am not sure if it is the FQ path being passed to the ZipOutputStream which is causing the problem. Either way, below is the code, which results in small (188kb) zip file (with no entries) being created. Any suggestions?

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Set;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

class FileZipper {

    public static void makeZip(Set fullyQualifiedFileNames, String zipFileName, String outDir) throws IOException, FileNotFoundException
    {
        // These are the files to include in the ZIP file
        Object[] filenames = fullyQualifiedFileNames.toArray();
        String fileSeparator =  (String) System.getProperties().get("file.separator");

        // Create a buffer for reading the files
        byte[] buf = new byte[1024];

        // Create the ZIP file
        String outFilename = outDir + fileSeparator +zipFileName;
        FileOutputStream fos = new FileOutputStream(outFilename);
        ZipOutputStream zos = new ZipOutputStream(fos);
        System.out.println("Zipping to file " +outFilename);
        // Compress the files

        for (Object fileName: filenames)
        {
            System.out.println("Adding file: " + fileName);
            FileInputStream fis = new FileInputStream((String)fileName);

            // Add ZIP entry to output stream.
            String[] nodes = ((String)fileName).split("[/[\\\\]]");
            String zipEntry = nodes[nodes.length-1];
            System.out.println("Adding Zip Entry: " + zipEntry);
            zos.putNextEntry(new ZipEntry((String)fileName));

            // Transfer bytes from the file to the ZIP file
            int len;
            int totalBytes = 0;
            while ((len = fis.read(buf)) > 0) 
            {
                totalBytes += len;
                zos.write(buf, 0, len);
            }
            System.out.println("Zipped " +totalBytes +" bytes");
            // Complete the entry
            zos.closeEntry();
            fis.close();
        }

        // Complete the ZIP file
        zos.close();
        fos.close();
    }
}

Answer 1

If you are using Groovy, the easiest way is using AntBuilder:

new AntBuilder().zip(
   destfile: "myfile.zip",
   basedir: "baseDir")

or as of Groovy 1.8:

ant.zip(destfile: 'file.zip', basedir: 'src_dir')