io.proximax.core.crypto.KeyPair Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of java-xpx-chain-sdk Show documentation
The ProximaX Sirius Chain Java SDK is a Java library for interacting with the Sirius Blockchain.
The newest version!
/*
 * Copyright 2018 NEM
 *
 * 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.proximax.core.crypto;

public class KeyPair {

    private final PrivateKey privateKey;
    private final PublicKey publicKey;

    /**
     * Creates a random key pair.
     */
    public KeyPair() {
        final KeyGenerator generator = CryptoEngines.defaultEngine().createKeyGenerator();
        final KeyPair pair = generator.generateKeyPair();
        this.privateKey = pair.getPrivateKey();
        this.publicKey = pair.getPublicKey();
    }

    /**
     * Creates a key pair around a private key.
     * The public key is calculated from the private key.
     *
     * @param privateKey The private key.
     */
    public KeyPair(final PrivateKey privateKey) {
        this(privateKey, CryptoEngines.defaultEngine());
    }

    /**
     * Creates a key pair around a private key.
     * The public key is calculated from the private key.
     *
     * @param privateKey The private key.
     * @param engine     The crypto engine.
     */
    public KeyPair(final PrivateKey privateKey, final CryptoEngine engine) {
        this(privateKey, engine.createKeyGenerator().derivePublicKey(privateKey), engine);
    }

    /**
     * Creates a key pair around a public key.
     * The private key is empty.
     *
     * @param publicKey The public key.
     */
    public KeyPair(final PublicKey publicKey) {
        this(publicKey, CryptoEngines.defaultEngine());
    }

    /**
     * Creates a key pair around a public key.
     * The private key is empty.
     *
     * @param publicKey The public key.
     * @param engine    The crypto engine.
     */
    public KeyPair(final PublicKey publicKey, final CryptoEngine engine) {
        this(null, publicKey, engine);
    }

    private KeyPair(final PrivateKey privateKey, final PublicKey publicKey, final CryptoEngine engine) {
        this.privateKey = privateKey;
        this.publicKey = publicKey;

        if (!engine.createKeyAnalyzer().isKeyCompressed(this.publicKey)) {
            throw new IllegalArgumentException("publicKey must be in compressed form");
        }
    }

    /**
     * Creates a random key pair that is compatible with the specified engine.
     *
     * @param engine The crypto engine.
     * @return The key pair.
     */
    public static KeyPair random(final CryptoEngine engine) {
        final KeyPair pair = engine.createKeyGenerator().generateKeyPair();
        return new KeyPair(pair.getPrivateKey(), pair.getPublicKey(), engine);
    }

    /**
     * Gets the private key.
     *
     * @return The private key.
     */
    public PrivateKey getPrivateKey() {
        return this.privateKey;
    }

    /**
     * Gets the public key.
     *
     * @return the public key.
     */
    public PublicKey getPublicKey() {
        return this.publicKey;
    }

    /**
     * Determines if the current key pair has a private key.
     *
     * @return true if the current key pair has a private key.
     */
    public boolean hasPrivateKey() {
        return null != this.privateKey;
    }

	@Override
	public String toString() {
		return "KeyPair [privateKey=" + privateKey + ", publicKey=" + publicKey + "]";
	}
    
    
}