Append Files to Existing Zip w/out Rewriting Entire Zip

Demonstrates how to use the QuickAppend method to append files to an existing .zip archive. This method works by editing the existing .zip -- it does not rewrite or recompress the contents of the existing .zip. It is the fastest way to append additional files to a pre-existing large .zip archive. Note: The QuickAppend method is new and available in the pre-release downloads, or in official releases dated after 6-October-2007.

Download Chilkat Java Library

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    CkZip zip = new CkZip();

    boolean success;

    //  Any string unlocks the component for the 1st 30-days.
    success = zip.UnlockComponent("Anything for 30-day trial");
    if (success != true) {
        System.out.println(zip.lastErrorText());
        return;
    }

    //  The NewZip method only initializes the Zip object -- it does
    //  not create or write a .zip file.
    success = zip.NewZip("notUsed.zip");
    if (success != true) {
        System.out.println(zip.lastErrorText());
        return;
    }

    //  Add a reference to a file.  This is the file that will
    //  be added to a pre-existing .zip archive.
    //  Note: this does not read or compress the file contents --
    //  it simply adds a reference to the zip object.
    boolean saveExtraPath;
    saveExtraPath = false;
    success = zip.AppendOneFileOrDir("something.dat",saveExtraPath);
    if (success != true) {
        System.out.println(zip.lastErrorText());
        return;
    }

    //  Appends the contents of the zip object to the preExisting.zip
    //  zip archive.  preExisting.zip is opened, and the files
    //  referenced by this zip object are streamed in, compressed,
    //  and appended to the end of the archive.
    success = zip.QuickAppend("preExisting.zip");
    if (success != true) {
        System.out.println(zip.lastErrorText());
        return;
    }

    System.out.println("Success!");

    //  Note: Additional files, directory trees, or in-memory data
    //  can be appended by calling AppendOneFileOrDir, AppendFiles,
    //  AppendString, AppendData, etc. multiple times.
    //  Whatever files and/or in-memory data that are referenced by
    //  this zip object will be appended to preExisting.zip when
    //  QuickAppend is called.

  }
}