Java tutorial
package org.bouncycastle.operator; import java.io.OutputStream; import org.bouncycastle.asn1.x509.AlgorithmIdentifier; /** * General interface for an operator that is able to create a signature from * a stream of output. */ public interface ContentSigner { /** * Return the algorithm identifier describing the signature * algorithm and parameters this signer generates. * * @return algorithm oid and parameters. */ AlgorithmIdentifier getAlgorithmIdentifier(); /** * Returns a stream that will accept data for the purpose of calculating * a signature. Use org.bouncycastle.util.io.TeeOutputStream if you want to accumulate * the data on the fly as well. * * @return an OutputStream */ OutputStream getOutputStream(); /** * Returns a signature based on the current data written to the stream, since the * start or the last call to getSignature(). * * @return bytes representing the signature. */ byte[] getSignature(); }