package org.spongycastle.openpgp.operator.jcajce;
import java.io.IOException;
import java.io.OutputStream;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.security.Provider;
import org.spongycastle.jcajce.DefaultJcaJceHelper;
import org.spongycastle.jcajce.NamedJcaJceHelper;
import org.spongycastle.jcajce.ProviderJcaJceHelper;
import org.spongycastle.openpgp.PGPException;
import org.spongycastle.openpgp.operator.PGPDigestCalculator;
import org.spongycastle.openpgp.operator.PGPDigestCalculatorProvider;
public class JcaPGPDigestCalculatorProviderBuilder
{
private OperatorHelper helper = new OperatorHelper(new DefaultJcaJceHelper());
public JcaPGPDigestCalculatorProviderBuilder()
{
}
public JcaPGPDigestCalculatorProviderBuilder setProvider(Provider provider)
{
this.helper = new OperatorHelper(new ProviderJcaJceHelper(provider));
return this;
}
public JcaPGPDigestCalculatorProviderBuilder setProvider(String providerName)
{
this.helper = new OperatorHelper(new NamedJcaJceHelper(providerName));
return this;
}
public PGPDigestCalculatorProvider build()
throws PGPException
{
return new PGPDigestCalculatorProvider()
{
public PGPDigestCalculator get(final int algorithm)
throws PGPException
{
final DigestOutputStream stream;
final MessageDigest dig;
try
{
dig = helper.createDigest(algorithm);
stream = new DigestOutputStream(dig);
}
catch (GeneralSecurityException e)
{
throw new PGPException("exception on setup: " + e, e);
}
return new PGPDigestCalculator()
{
public int getAlgorithm()
{
return algorithm;
}
public OutputStream getOutputStream()
{
return stream;
}
public byte[] getDigest()
{
return stream.getDigest();
}
public void reset()
{
dig.reset();
}
};
}
};
}
private class DigestOutputStream
extends OutputStream
{
private MessageDigest dig;
DigestOutputStream(MessageDigest dig)
{
this.dig = dig;
}
public void write(byte[] bytes, int off, int len)
throws IOException
{
dig.update(bytes, off, len);
}
public void write(byte[] bytes)
throws IOException
{
dig.update(bytes);
}
public void write(int b)
throws IOException
{
dig.update((byte)b);
}
byte[] getDigest()
{
return dig.digest();
}
}
}