001/*
002 * SPDX-License-Identifier: Apache-2.0
003 *
004 * Copyright 2025-2026 The Enola <https://enola.dev> Authors
005 *
006 * Licensed under the Apache License, Version 2.0 (the "License");
007 * you may not use this file except in compliance with the License.
008 * You may obtain a copy of the License at
009 *
010 *     https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package dev.enola.common.secret;
019
020import java.io.IOException;
021import java.util.Optional;
022
023/**
024 * SecretManager that reads secrets from the JVM properties (AKA <code>java -D...</code>).
025 *
026 * <p>This is not very secure, and really only marginally better than the {@link
027 * EnvironmentSecretManager} (because JVM process launch parameters are often still too broadly
028 * visible). Other implementations are preferred - but sometimes this may be useful.
029 */
030public class JavaPropertySecretManager extends ReadOnlySecretManager {
031
032    @Override
033    @SuppressWarnings("deprecation")
034    public Optional<Secret> getOptional(String key) throws IOException {
035        String value = System.getProperty(key);
036        return Optional.ofNullable(value).map(Secret::new);
037    }
038}