Create Password Protected Zip containing a Single File.

Create a password-protected .zip containing a single file. (This uses the older Zip 2.0 encryption scheme, which is weaker and not as secure as AES encryption, which Chilkat Zip also supports.)

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;
    }

    success = zip.NewZip("test.zip");
    if (success != true) {
        System.out.println(zip.lastErrorText());
        return;
    }

    zip.SetPassword("secret");
    zip.put_PasswordProtect(true);

    boolean saveExtraPath;
    saveExtraPath = false;
    success = zip.AppendOneFileOrDir("c:/temp/hamlet.xml",saveExtraPath);

    success = zip.WriteZipAndClose();
    if (success != true) {
        System.out.println(zip.lastErrorText());
        return;
    }

    System.out.println("Zip Created!");
  }
}