| /* MeteredInputStream.java -- |
| Copyright (C) 2003, 2006 Free Software Foundation, Inc. |
| |
| This file is a part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or (at |
| your option) any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 |
| USA |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.javax.crypto.keyring; |
| |
| import java.io.FilterInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| |
| final class MeteredInputStream |
| extends FilterInputStream |
| { |
| private int count; |
| private final int limit; |
| |
| MeteredInputStream(InputStream in, int limit) |
| { |
| super(in); |
| if (limit < 0) |
| throw new IllegalArgumentException("limit must be nonnegative"); |
| this.limit = limit; |
| count = 0; |
| } |
| |
| /** |
| * Tests if the number of bytes read has reached the limit. |
| * |
| * @return True if the limit has been reached. |
| */ |
| public boolean limitReached() |
| { |
| return count == limit; |
| } |
| |
| public int available() throws IOException |
| { |
| return Math.min(in.available(), limit - count); |
| } |
| |
| public void close() throws IOException |
| { |
| in.close(); |
| } |
| |
| public void mark(int readLimit) |
| { |
| } |
| |
| public boolean markSupported() |
| { |
| return false; |
| } |
| |
| public int read() throws IOException |
| { |
| if (limitReached()) |
| return -1; |
| int i = in.read(); |
| if (i != -1) |
| count++; |
| return i; |
| } |
| |
| public int read(byte[] buf) throws IOException |
| { |
| return read(buf, 0, buf.length); |
| } |
| |
| public int read(byte[] buf, int off, int len) throws IOException |
| { |
| if (limitReached()) |
| return -1; |
| int i = in.read(buf, off, Math.min(len, limit - count)); |
| if (i != -1) |
| count += i; |
| return i; |
| } |
| |
| public void reset() throws IOException |
| { |
| } |
| |
| public long skip(long len) throws IOException |
| { |
| if (limitReached()) |
| return 0L; |
| len = Math.min(len, limit - count); |
| len = in.skip(len); |
| count += (int) len; |
| return len; |
| } |
| } |