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

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

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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[])
  {
    // 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) {
        System.out.println(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) {
        System.out.println("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) {
        System.out.println("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();
  }
}