FileDocCategorySizeDatePackage
Compress.javaAPI DocExample3928Mon Sep 22 13:30:32 BST 1997None

Compress

public class Compress extends Object
This class defines two static methods for gzipping files and zipping directories. It also defines a demonstration program as a nested class.

Fields Summary
Constructors Summary
Methods Summary
public static voidgzipFile(java.lang.String from, java.lang.String to)
Gzip the contents of the from file and save in the to file.

    // Create stream to read from the from file
    FileInputStream in = new FileInputStream(from);
    // Create stream to compress data and write it to the to file.
    GZIPOutputStream out = new GZIPOutputStream(new FileOutputStream(to));
    // Copy bytes from one stream to the other
    byte[] buffer = new byte[4096];
    int bytes_read;
    while((bytes_read = in.read(buffer)) != -1) 
      out.write(buffer, 0, bytes_read);
    // And close the streams
    in.close();
    out.close();
public static voidzipDirectory(java.lang.String dir, java.lang.String zipfile)
Zip the contents of the directory, and save it in the zipfile

    // Check that the directory is a directory, and get its contents
    File d = new File(dir);
    if (!d.isDirectory())
      throw new IllegalArgumentException("Compress: not a directory:  " + dir);
    String[] entries = d.list();
    byte[] buffer = new byte[4096];  // Create a buffer for copying 
    int bytes_read;

    // Create a stream to compress data and write it to the zipfile
    ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipfile));

    // Loop through all entries in the directory
    for(int i = 0; i < entries.length; i++) {
      File f = new File(d, entries[i]);
      if (f.isDirectory()) continue;               // Don't zip sub-directories
      FileInputStream in = new FileInputStream(f); // Stream to read file
      ZipEntry entry = new ZipEntry(f.getPath());  // Make a ZipEntry
      out.putNextEntry(entry);                     // Store entry in zipfile
      while((bytes_read = in.read(buffer)) != -1)  // Copy bytes to zipfile
        out.write(buffer, 0, bytes_read);
      in.close();                                  // Close input stream
    }
    // When we're done with the whole loop, close the output stream
    out.close();