/*
 * Copyright (C) 2021 jsonwebtoken.io
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.jsonwebtoken.security;

import java.security.Key;

/**
 * Provides access to a cryptographic {@link Key} necessary for signing, wrapping, encryption or decryption algorithms.
 *
 * @param <K> the type of key provided by this supplier.
 * @since JJWT_RELEASE_VERSION
 */
public interface KeySupplier<K extends Key> {

    /**
     * Returns the key to use for signing, wrapping, encryption or decryption depending on the type of operation.
     *
     * @return the key to use for signing, wrapping, encryption or decryption depending on the type of operation.
     */
    K getKey();
}
