Java tutorial
/** * Copyright 2015 DuraSpace, Inc. * * 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 org.fcrepo.kernel.impl.utils; import java.io.InputStream; import java.security.DigestInputStream; import java.security.MessageDigest; import org.apache.commons.io.input.CountingInputStream; /** * An InputStream wrapper that calculates the size and digest * while reading from the stream. * @author Chris Beer * @since Mar 12, 2013 */ public class FixityInputStream extends CountingInputStream { /** * Creates a <code>FilterInputStream</code> by assigning the * argument <code>in</code> to the field <code>this.in</code> * so as to remember it for later use. * * @param in the underlying input stream, or <code>null</code> if * this instance is to be created without an underlying stream. * @param digest the given digest */ public FixityInputStream(final InputStream in, final MessageDigest digest) { super(new DigestInputStream(in, digest)); } /** * Retrieve the calculated digest for the input stream * @return digest for this input stream */ public MessageDigest getMessageDigest() { return ((DigestInputStream) in).getMessageDigest(); } }