org.apache.xmlrpc.util.LimitedInputStream Maven / Gradle / Ivy
/*
* Copyright 1999,2005 The Apache Software Foundation.
*
* Licensed 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.xmlrpc.util;
import java.io.InputStream;
import java.io.IOException;
/** A filtering {@link java.io.InputStream} for proper handling of
* the Content-Length header: It guarantees to return
* at most a given number of bytes.
*/
public class LimitedInputStream extends InputStream {
// bytes remaining to be read from the input stream. This is
// initialized from CONTENT_LENGTH (or getContentLength()).
// This is used in order to correctly return a -1 when all the
// data POSTed was read. If this is left to -1, content length is
// assumed as unknown and the standard InputStream methods will be used
private long available;
private long markedAvailable;
private InputStream in;
/** Creates a new instance, reading from the given input stream
* and returning at most the given number of bytes.
* @param pIn Input stream being read.
* @param pAvailable Number of bytes available in pIn.
*/
public LimitedInputStream(InputStream pIn, int pAvailable) {
in = pIn;
available = pAvailable;
}
public int read() throws IOException {
if (available > 0) {
available--;
return in.read();
}
return -1;
}
public int read(byte b[], int off, int len) throws IOException {
if (available > 0) {
if (len > available) {
// shrink len
len = (int) available;
}
int read = in.read(b, off, len);
if (read == -1) {
available = 0;
} else {
available -= read;
}
return read;
}
return -1;
}
public long skip(long n) throws IOException {
long skip = in.skip(n);
if (available > 0) {
available -= skip;
}
return skip;
}
public void mark(int readlimit) {
in.mark(readlimit);
markedAvailable = available;
}
public void reset() throws IOException {
in.reset();
available = markedAvailable;
}
public boolean markSupported() {
return true;
}
}