    001/*
    002 * $HeadURL: http://juliusdavies.ca/svn/not-yet-commons-ssl/tags/commons-ssl-0.3.15/src/java/org/apache/commons/ssl/ComboInputStream.java $
    003 * $Revision: 121 $
    004 * $Date: 2007-11-13 21:26:57 -0800 (Tue, 13 Nov 2007) $
    005 *
    006 * ====================================================================
    007 * Licensed to the Apache Software Foundation (ASF) under one
    008 * or more contributor license agreements.  See the NOTICE file
    009 * distributed with this work for additional information
    010 * regarding copyright ownership.  The ASF licenses this file
    011 * to you under the Apache License, Version 2.0 (the
    012 * "License"); you may not use this file except in compliance
    013 * with the License.  You may obtain a copy of the License at
    014 *
    015 *   http://www.apache.org/licenses/LICENSE-2.0
    016 *
    017 * Unless required by applicable law or agreed to in writing,
    018 * software distributed under the License is distributed on an
    019 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    020 * KIND, either express or implied.  See the License for the
    021 * specific language governing permissions and limitations
    022 * under the License.
    023 * ====================================================================
    024 *
    025 * This software consists of voluntary contributions made by many
    026 * individuals on behalf of the Apache Software Foundation.  For more
    027 * information on the Apache Software Foundation, please see
    028 * <http://www.apache.org/>.
    029 *
    030 */
    031
    032package org.apache.commons.ssl;
    033
    034import java.io.IOException;
    035import java.io.InputStream;
    036
    037/**
    038 * @author Credit Union Central of British Columbia
    039 * @author <a href="http://www.cucbc.com/">www.cucbc.com</a>
    040 * @author <a href="mailto:juliusdavies@cucbc.com">juliusdavies@cucbc.com</a>
    041 * @since 22-Feb-2007
    042 */
    043public class ComboInputStream extends InputStream {
    044    private boolean headDone;
    045    private InputStream head;
    046    private InputStream tail;
    047
    048    public ComboInputStream(InputStream head, InputStream tail) {
    049        this.head = head != null ? head : tail;
    050        this.tail = tail != null ? tail : head;
    051    }
    052
    053    public int read() throws IOException {
    054        int c;
    055        if (headDone) {
    056            c = tail.read();
    057        } else {
    058            c = head.read();
    059            if (c == -1) {
    060                headDone = true;
    061                c = tail.read();
    062            }
    063        }
    064        return c;
    065    }
    066
    067    public int available() throws IOException {
    068        return tail.available() + head.available();
    069    }
    070
    071    public void close() throws IOException {
    072        try {
    073            head.close();
    074        }
    075        finally {
    076            if (head != tail) {
    077                tail.close();
    078            }
    079        }
    080    }
    081
    082    public int read(byte b[], int off, int len) throws IOException {
    083        int c;
    084        if (headDone) {
    085            c = tail.read(b, off, len);
    086        } else {
    087            c = head.read(b, off, len);
    088            if (c == -1) {
    089                headDone = true;
    090                c = tail.read(b, off, len);
    091            }
    092        }
    093        return c;
    094    }
    095
    096}