(Android™) Determine if a Zip is Encrypted or Password-Protected

Determines whether or not a zip archive is AES encrypted or password-protected.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkZip zip = new CkZip();

    // An encrypted or password-protected zip can be opened
    // without specifying the password.  However, the contents
    // of the files cannot be unzipped without providing the correct
    // password.

    boolean success = zip.OpenZip("something.zip");
    if (success != true) {
        Log.i(TAG, zip.lastErrorText());
        return;
        }

    // If the zip is password-protected, meaning that it uses
    // the old (insecure) Zip 2.0 encryption, then the
    // PasswordProtect property will be true
    boolean bPwdProt = zip.get_PasswordProtect();
    if (bPwdProt) {
        Log.i(TAG, "This zip is password-protected.");
        }

    // If the zip is AES encrypted (WinZip compatible) then
    // the Encryption property will be equal to 4.
    int encValue = zip.get_Encryption();
    if (encValue == 4) {
        Log.i(TAG, "This zip is AES encrypted.");
        }

    // If the Encryption property = 0, then the zip is NOT
    // strong encrypted, and is either password-protected or
    // entirely unencrypted, depending on the value of the
    // PasswordProtect property.

    zip.CloseZip();

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}