| /**************************************************************** |
| * 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.dom; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| |
| /** |
| * Abstract implementation of a single message body; that is, a body that does |
| * not contain (directly or indirectly) any other child bodies. It also provides |
| * the parent functionality required by bodies. |
| */ |
| public abstract class SingleBody implements Body { |
| |
| private Entity parent = null; |
| |
| /** |
| * Sole constructor. |
| */ |
| protected SingleBody() { |
| } |
| |
| /** |
| * @see org.apache.james.mime4j.dom.Body#getParent() |
| */ |
| public Entity getParent() { |
| return parent; |
| } |
| |
| /** |
| * @see org.apache.james.mime4j.dom.Body#setParent(org.apache.james.mime4j.dom.Entity) |
| */ |
| public void setParent(Entity parent) { |
| this.parent = parent; |
| } |
| |
| /** |
| * Gets a <code>InputStream</code> which reads the bytes of the body. |
| * |
| * @return the stream, transfer decoded |
| * @throws IOException |
| * on I/O errors. |
| */ |
| public abstract InputStream getInputStream() throws IOException; |
| |
| /** |
| * Writes this single body to the given stream. The default implementation copies |
| * the input stream obtained by {@link #getInputStream()} to the specified output |
| * stream. May be overwritten by a subclass to improve performance. |
| * |
| * @param out |
| * the stream to write to. |
| * @throws IOException |
| * in case of an I/O error |
| */ |
| public void writeTo(OutputStream out) throws IOException { |
| if (out == null) |
| throw new IllegalArgumentException(); |
| |
| InputStream in = getInputStream(); |
| SingleBody.copy(in, out); |
| in.close(); |
| } |
| |
| /** |
| * Returns a copy of this <code>SingleBody</code> (optional operation). |
| * <p> |
| * The general contract of this method is as follows: |
| * <ul> |
| * <li>Invoking {@link #getParent()} on the copy returns <code>null</code>. |
| * That means that the copy is detached from the parent entity of this |
| * <code>SingleBody</code>. The copy may get attached to a different |
| * entity later on.</li> |
| * <li>The underlying content does not have to be copied. Instead it may be |
| * shared between multiple copies of a <code>SingleBody</code>.</li> |
| * <li>If the underlying content is shared by multiple copies the |
| * implementation has to make sure that the content gets deleted when the |
| * last copy gets disposed of (and not before that).</li> |
| * </ul> |
| * <p> |
| * This implementation always throws an |
| * <code>UnsupportedOperationException</code>. |
| * |
| * @return a copy of this <code>SingleBody</code>. |
| * @throws UnsupportedOperationException |
| * if the <code>copy</code> operation is not supported by this |
| * single body. |
| */ |
| public SingleBody copy() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * Subclasses should override this method if they have allocated resources |
| * that need to be freed explicitly (e.g. cannot be simply reclaimed by the |
| * garbage collector). |
| * |
| * The default implementation of this method does nothing. |
| * |
| * @see org.apache.james.mime4j.dom.Disposable#dispose() |
| */ |
| public void dispose() { |
| } |
| |
| static final int DEFAULT_ENCODING_BUFFER_SIZE = 1024; |
| |
| /** |
| * Copies the contents of one stream to the other. |
| * @param in not null |
| * @param out not null |
| * @throws IOException |
| */ |
| private static void copy(final InputStream in, final OutputStream out) throws IOException { |
| final byte[] buffer = new byte[DEFAULT_ENCODING_BUFFER_SIZE]; |
| int inputLength; |
| while (-1 != (inputLength = in.read(buffer))) { |
| out.write(buffer, 0, inputLength); |
| } |
| } |
| |
| } |