org.nuthatchery.pica.util.Signature.java Source code

Introduction

Here is the source code for org.nuthatchery.pica.util.Signature.java

Source

/**************************************************************************
 * Copyright (c) 2012 Anya Helene Bagge
 * Copyright (c) 2012 University of Bergen
 * 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version. See http://www.gnu.org/licenses/
 * 
 * 
 * See the file COPYRIGHT for more information.
 * 
 * Contributors:
 * * Anya Helene Bagge
 * 
 *************************************************************************/
package org.nuthatchery.pica.util;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.MessageDigest;
import java.util.Arrays;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Hex;

public class Signature implements ISignature {

    private final byte[] signature;

    public Signature(byte[] signature) {
        this.signature = Arrays.copyOf(signature, signature.length);
    }

    public Signature(int i) {
        signature = new byte[] { (byte) i, (byte) (i >>> 8), (byte) (i >>> 16), (byte) (i >>> 24) };
    }

    public Signature(String hexString) throws DecoderException {
        this.signature = Hex.decodeHex(hexString.toCharArray());
    }

    /**
     * @param foo
     */
    private Signature(InputStream stream, int length) throws IOException {
        signature = new byte[length];
        int read = stream.read(signature);
        if (read != length) {
            throw new IOException("Short read: expected " + length + " bytes, got " + read);
        }
    }

    @Override
    public void digest(MessageDigest md) {
        md.update(signature);
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        byte[] bytes;
        if (obj instanceof Signature) {
            bytes = ((Signature) obj).signature;
        } else if (obj instanceof ISignature) {
            bytes = ((ISignature) obj).toBytes();
        } else {
            return false;
        }
        if (!Arrays.equals(signature, bytes)) {
            return false;
        }
        return true;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + Arrays.hashCode(signature);
        return result;
    }

    @Override
    public ISignature readFrom(InputStream stream) throws IOException {
        return new Signature(stream, signature.length);
    }

    @Override
    public byte[] toBytes() {
        return Arrays.copyOf(signature, signature.length);
    }

    @Override
    public String toHexString() {
        return String.valueOf(Hex.encodeHex(signature));
    }

    @Override
    public ISignature valueOf(byte[] bytes) {
        return new Signature(bytes);
    }

    @Override
    public ISignature valueOf(String hexString) throws DecoderException {
        return new Signature(hexString);
    }

    @Override
    public void writeTo(OutputStream stream) throws IOException {
        stream.write(signature);
    }

}