зеркало из https://github.com/mozilla/gecko-dev.git
76 строки
2.0 KiB
Java
76 строки
2.0 KiB
Java
/* -*- Mode: java; indent-tabs-mode: nil; c-basic-offset: 2 -*-
|
|
*
|
|
* The contents of this file are subject to the Mozilla Public License
|
|
* Version 1.0 (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.mozilla.org/MPL/
|
|
*
|
|
* Software distributed under the License is distributed on an "AS IS"
|
|
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
|
|
* the License for the specific language governing rights and limitations
|
|
* under the License.
|
|
*
|
|
* The Original Code is the Grendel mail/news client.
|
|
*
|
|
* The Initial Developer of the Original Code is Netscape Communications
|
|
* Corporation. Portions created by Netscape are Copyright (C) 1997
|
|
* Netscape Communications Corporation. All Rights Reserved.
|
|
*
|
|
* Created: Terry Weissman <terry@netscape.com>, 28 Aug 1997.
|
|
*/
|
|
|
|
package grendel.storage;
|
|
|
|
import java.io.File;
|
|
import java.io.FileInputStream;
|
|
import java.io.FileNotFoundException;
|
|
import java.io.InputStream;
|
|
import java.io.IOException;
|
|
|
|
/** Implements an input stream that comes from just a portion of a file. */
|
|
|
|
class PartialFileInputStream extends FileInputStream {
|
|
int remaining = 1 << 30;
|
|
|
|
public PartialFileInputStream(File f, int start, int length)
|
|
throws IOException, FileNotFoundException
|
|
{
|
|
super(f);
|
|
skip(start);
|
|
remaining = length;
|
|
}
|
|
|
|
public int read() throws IOException {
|
|
if (remaining <= 0) return -1;
|
|
remaining--;
|
|
return super.read();
|
|
}
|
|
|
|
public int read(byte b[]) throws IOException {
|
|
if (remaining <= 0) return -1;
|
|
int result = super.read(b);
|
|
if (result > 0) {
|
|
if (result > remaining) result = remaining;
|
|
remaining -= result;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
public int read(byte b[], int off, int length) throws IOException {
|
|
if (remaining <= 0) return -1;
|
|
if (length > remaining) length = remaining;
|
|
int result = super.read(b, off, length);
|
|
if (result > 0) {
|
|
if (result > remaining) result = remaining;
|
|
remaining -= result;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|