public void openProtection(DecryptionMaterial decryptionMaterial) throws IOException
{
if (isEncrypted())
{
SecurityHandler securityHandler = getEncryption().getSecurityHandler();
securityHandler.decryptDocument(this, decryptionMaterial);
accessPermission = securityHandler.getCurrentAccessPermission();
document.dereferenceObjectStreams();
document.setEncryptionDictionary(null);
getDocumentCatalog();
}