core/src/main/java/com/orientechnologies/orient/core/security/symmetrickey/OSymmetricKey.java
public String encrypt(final String value) {
    try {
      return encrypt(value.getBytes("UTF8"));
    } catch (Exception ex) {
      throw OException.wrapException(new OSecurityException("OSymmetricKey.encrypt() Exception: " + ex.getMessage()), ex);
    }
  }
public String encrypt(final String value) {
    try {
      return encrypt(value.getBytes("UTF8"));
    } catch (Exception ex) {
      throw OException.wrapException(new OSecurityException("OSymmetricKey.encrypt() Exception: " + ex.getMessage()), ex);
    }
  }
This is a convenience method that takes a String argument, encodes it as Base64, then calls encrypt(byte[]).

@param value The String to be encoded to Base64 then encrypted.

@return A Base64-encoded JSON document.