зеркало из https://github.com/mozilla/pjs.git
76 строки
2.0 KiB
Java
76 строки
2.0 KiB
Java
/* -*- Mode: java; indent-tabs-mode: nil; c-basic-offset: 2 -*-
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*
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* The contents of this file are subject to the Mozilla Public License
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* Version 1.0 (the "License"); you may not use this file except in
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* compliance with the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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*
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* Software distributed under the License is distributed on an "AS IS"
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* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
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* the License for the specific language governing rights and limitations
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* under the License.
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*
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* The Original Code is the Grendel mail/news client.
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*
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* The Initial Developer of the Original Code is Netscape Communications
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* Corporation. Portions created by Netscape are Copyright (C) 1997
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* Netscape Communications Corporation. All Rights Reserved.
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*
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* Created: Terry Weissman <terry@netscape.com>, 28 Aug 1997.
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*/
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package grendel.storage;
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import java.io.File;
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import java.io.FileInputStream;
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import java.io.FileNotFoundException;
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import java.io.InputStream;
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import java.io.IOException;
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/** Implements an input stream that comes from just a portion of a file. */
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class PartialFileInputStream extends FileInputStream {
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int remaining = 1 << 30;
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public PartialFileInputStream(File f, int start, int length)
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throws IOException, FileNotFoundException
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{
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super(f);
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skip(start);
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remaining = length;
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}
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public int read() throws IOException {
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if (remaining <= 0) return -1;
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remaining--;
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return super.read();
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}
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public int read(byte b[]) throws IOException {
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if (remaining <= 0) return -1;
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int result = super.read(b);
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if (result > 0) {
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if (result > remaining) result = remaining;
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remaining -= result;
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}
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return result;
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}
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public int read(byte b[], int off, int length) throws IOException {
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if (remaining <= 0) return -1;
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if (length > remaining) length = remaining;
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int result = super.read(b, off, length);
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if (result > 0) {
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if (result > remaining) result = remaining;
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remaining -= result;
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}
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return result;
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}
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}
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