- /*
- * $Header: /home/cvs/jakarta-commons/httpclient/src/java/org/apache/commons/httpclient/ContentLengthInputStream.java,v 1.11 2004/08/09 01:25:54 mbecke Exp $
- * $Revision: 1.11 $
- * $Date: 2004/08/09 01:25:54 $
- *
- * ====================================================================
- *
- * Copyright 1999-2004 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.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- *
- */
-
- package org.apache.commons.httpclient;
-
- import java.io.FilterInputStream;
- import java.io.IOException;
- import java.io.InputStream;
-
- /**
- * Cuts the wrapped InputStream off after a specified number of bytes.
- *
- * @author Ortwin Gl???ck
- * @author Eric Johnson
- * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
- * @since 2.0
- */
- public class ContentLengthInputStream extends FilterInputStream {
-
- /**
- * The maximum number of bytes that can be read from the stream. Subsequent
- * read operations will return -1.
- */
- private long contentLength;
-
- /** The current position */
- private long pos = 0;
-
- /** True if the stream is closed. */
- private boolean closed = false;
-
- /**
- * @deprecated use {@link #ContentLengthInputStream(InputStream, long)}
- *
- * Creates a new length limited stream
- *
- * @param in The stream to wrap
- * @param contentLength The maximum number of bytes that can be read from
- * the stream. Subsequent read operations will return -1.
- */
- public ContentLengthInputStream(InputStream in, int contentLength) {
- super(in);
- this.contentLength = contentLength;
- }
-
- /**
- * Creates a new length limited stream
- *
- * @param in The stream to wrap
- * @param contentLength The maximum number of bytes that can be read from
- * the stream. Subsequent read operations will return -1.
- *
- * @since 3.0
- */
- public ContentLengthInputStream(InputStream in, long contentLength) {
- super(in);
- this.contentLength = contentLength;
- }
-
- /**
- * <p>Reads until the end of the known length of content.</p>
- *
- * <p>Does not close the underlying socket input, but instead leaves it
- * primed to parse the next response.</p>
- * @throws IOException If an IO problem occurs.
- */
- public void close() throws IOException {
- if (!closed) {
- try {
- ChunkedInputStream.exhaustInputStream(this);
- } finally {
- // close after above so that we don't throw an exception trying
- // to read after closed!
- closed = true;
- }
- }
- }
-
-
- /**
- * Read the next byte from the stream
- * @return The next byte or -1 if the end of stream has been reached.
- * @throws IOException If an IO problem occurs
- * @see java.io.InputStream#read()
- */
- public int read() throws IOException {
- if (closed) {
- throw new IOException("Attempted read from closed stream.");
- }
-
- if (pos >= contentLength) {
- return -1;
- }
- pos++;
- return super.read();
- }
-
- /**
- * Does standard {@link InputStream#read(byte[], int, int)} behavior, but
- * also notifies the watcher when the contents have been consumed.
- *
- * @param b The byte array to fill.
- * @param off Start filling at this position.
- * @param len The number of bytes to attempt to read.
- * @return The number of bytes read, or -1 if the end of content has been
- * reached.
- *
- * @throws java.io.IOException Should an error occur on the wrapped stream.
- */
- public int read (byte[] b, int off, int len) throws java.io.IOException {
- if (closed) {
- throw new IOException("Attempted read from closed stream.");
- }
-
- if (pos >= contentLength) {
- return -1;
- }
-
- if (pos + len > contentLength) {
- len = (int) (contentLength - pos);
- }
- int count = super.read(b, off, len);
- pos += count;
- return count;
- }
-
-
- /**
- * Read more bytes from the stream.
- * @param b The byte array to put the new data in.
- * @return The number of bytes read into the buffer.
- * @throws IOException If an IO problem occurs
- * @see java.io.InputStream#read(byte[])
- */
- public int read(byte[] b) throws IOException {
- return read(b, 0, b.length);
- }
-
- /**
- * Skips and discards a number of bytes from the input stream.
- * @param n The number of bytes to skip.
- * @return The actual number of bytes skipped. <= 0 if no bytes
- * are skipped.
- * @throws IOException If an error occurs while skipping bytes.
- * @see InputStream#skip(long)
- */
- public long skip(long n) throws IOException {
- // make sure we don't skip more bytes than are
- // still available
- long length = Math.min(n, contentLength - pos);
- // skip and keep track of the bytes actually skipped
- length = super.skip(length);
- // only add the skipped bytes to the current position
- // if bytes were actually skipped
- if (length > 0) {
- pos += length;
- }
- return length;
- }
- }