| /**************************************************************** |
| * Licensed to the Apache Software Foundation (ASF) under one * |
| * or more contributor license agreements. See the NOTICE file * |
| * distributed with this work for additional information * |
| * regarding copyright ownership. The ASF licenses this file * |
| * to you 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.apache.james.mime4j; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.PushbackInputStream; |
| |
| /** |
| * Stream that constrains itself to a single MIME body part. |
| * After the stream ends (i.e. read() returns -1) {@link #hasMoreParts()} |
| * can be used to determine if a final boundary has been seen or not. |
| * If {@link #parentEOF()} is <code>true</code> an unexpected end of stream |
| * has been detected in the parent stream. |
| * |
| * |
| * |
| * @version $Id: MimeBoundaryInputStream.java,v 1.2 2004/11/29 13:15:42 ntherning Exp $ |
| */ |
| public class MimeBoundaryInputStream extends InputStream { |
| |
| private PushbackInputStream s = null; |
| private byte[] boundary = null; |
| private boolean first = true; |
| private boolean eof = false; |
| private boolean parenteof = false; |
| private boolean moreParts = true; |
| |
| /** |
| * Creates a new MimeBoundaryInputStream. |
| * @param s The underlying stream. |
| * @param boundary Boundary string (not including leading hyphens). |
| */ |
| public MimeBoundaryInputStream(InputStream s, String boundary) |
| throws IOException { |
| |
| this.s = new PushbackInputStream(s, boundary.length() + 4); |
| |
| boundary = "--" + boundary; |
| this.boundary = new byte[boundary.length()]; |
| for (int i = 0; i < this.boundary.length; i++) { |
| this.boundary[i] = (byte) boundary.charAt(i); |
| } |
| |
| /* |
| * By reading one byte we will update moreParts to be as expected |
| * before any bytes have been read. |
| */ |
| int b = read(); |
| if (b != -1) { |
| this.s.unread(b); |
| } |
| } |
| |
| /** |
| * Closes the underlying stream. |
| * |
| * @throws IOException on I/O errors. |
| */ |
| public void close() throws IOException { |
| s.close(); |
| } |
| |
| /** |
| * Determines if the underlying stream has more parts (this stream has |
| * not seen an end boundary). |
| * |
| * @return <code>true</code> if there are more parts in the underlying |
| * stream, <code>false</code> otherwise. |
| */ |
| public boolean hasMoreParts() { |
| return moreParts; |
| } |
| |
| /** |
| * Determines if the parent stream has reached EOF |
| * |
| * @return <code>true</code> if EOF has been reached for the parent stream, |
| * <code>false</code> otherwise. |
| */ |
| public boolean parentEOF() { |
| return parenteof; |
| } |
| |
| /** |
| * Consumes all unread bytes of this stream. After a call to this method |
| * this stream will have reached EOF. |
| * |
| * @throws IOException on I/O errors. |
| */ |
| public void consume() throws IOException { |
| while (read() != -1) { |
| } |
| } |
| |
| /** |
| * @see java.io.InputStream#read() |
| */ |
| public int read() throws IOException { |
| if (eof) { |
| return -1; |
| } |
| |
| if (first) { |
| first = false; |
| if (matchBoundary()) { |
| return -1; |
| } |
| } |
| |
| int b1 = s.read(); |
| int b2 = s.read(); |
| |
| if (b1 == '\r' && b2 == '\n') { |
| if (matchBoundary()) { |
| return -1; |
| } |
| } |
| |
| if (b2 != -1) { |
| s.unread(b2); |
| } |
| |
| parenteof = b1 == -1; |
| eof = parenteof; |
| |
| return b1; |
| } |
| |
| private boolean matchBoundary() throws IOException { |
| |
| for (int i = 0; i < boundary.length; i++) { |
| int b = s.read(); |
| if (b != boundary[i]) { |
| if (b != -1) { |
| s.unread(b); |
| } |
| for (int j = i - 1; j >= 0; j--) { |
| s.unread(boundary[j]); |
| } |
| return false; |
| } |
| } |
| |
| /* |
| * We have a match. Is it an end boundary? |
| */ |
| int prev = s.read(); |
| int curr = s.read(); |
| moreParts = !(prev == '-' && curr == '-'); |
| do { |
| if (curr == '\n' && prev == '\r') { |
| break; |
| } |
| prev = curr; |
| } while ((curr = s.read()) != -1); |
| |
| if (curr == -1) { |
| moreParts = false; |
| parenteof = true; |
| } |
| |
| eof = true; |
| |
| return true; |
| } |
| } |