org.springframework.security.crypto.keygen.Base64StringKeyGenerator Maven / Gradle / Ivy
/*
* Copyright 2002-2018 the original author or authors.
*
* 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
*
* https://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 org.springframework.security.crypto.keygen;
import java.util.Base64;
/**
* A StringKeyGenerator that generates base64-encoded String keys. Delegates to a
* {@link BytesKeyGenerator} for the actual key generation.
*
* @author Joe Grandja
* @author Rob Winch
* @since 5.0
*/
public class Base64StringKeyGenerator implements StringKeyGenerator {
private static final int DEFAULT_KEY_LENGTH = 32;
private final BytesKeyGenerator keyGenerator;
private final Base64.Encoder encoder;
/**
* Creates an instance with keyLength of 32 bytes and standard Base64 encoding.
*/
public Base64StringKeyGenerator() {
this(DEFAULT_KEY_LENGTH);
}
/**
* Creates an instance with the provided key length in bytes and standard Base64
* encoding.
* @param keyLength the key length in bytes
*/
public Base64StringKeyGenerator(int keyLength) {
this(Base64.getEncoder(), keyLength);
}
/**
* Creates an instance with keyLength of 32 bytes and the provided encoder.
* @param encoder the encoder to use
*/
public Base64StringKeyGenerator(Base64.Encoder encoder) {
this(encoder, DEFAULT_KEY_LENGTH);
}
/**
* Creates an instance with the provided key length and encoder.
* @param encoder the encoder to use
* @param keyLength the key length to use
*/
public Base64StringKeyGenerator(Base64.Encoder encoder, int keyLength) {
if (encoder == null) {
throw new IllegalArgumentException("encode cannot be null");
}
if (keyLength < DEFAULT_KEY_LENGTH) {
throw new IllegalArgumentException("keyLength must be greater than or equal to" + DEFAULT_KEY_LENGTH);
}
this.encoder = encoder;
this.keyGenerator = KeyGenerators.secureRandom(keyLength);
}
@Override
public String generateKey() {
byte[] key = this.keyGenerator.generateKey();
byte[] base64EncodedKey = this.encoder.encode(key);
return new String(base64EncodedKey);
}
}