org.apache.coyote.http11.filters.VoidInputFilter Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.coyote.http11.filters;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import org.apache.coyote.InputBuffer;
import org.apache.coyote.Request;
import org.apache.coyote.http11.InputFilter;
import org.apache.tomcat.util.buf.ByteChunk;
/**
* Void input filter, which returns -1 when attempting a read. Used with a GET,
* HEAD, or a similar request.
*
* @author Remy Maucherat
*/
public class VoidInputFilter implements InputFilter {
// -------------------------------------------------------------- Constants
protected static final String ENCODING_NAME = "void";
protected static final ByteChunk ENCODING = new ByteChunk();
// ----------------------------------------------------- Static Initializer
static {
ENCODING.setBytes(ENCODING_NAME.getBytes(StandardCharsets.ISO_8859_1),
0, ENCODING_NAME.length());
}
// ----------------------------------------------------- Instance Variables
// Tracks if an attempt has been made to read data
private boolean read = false;
// ---------------------------------------------------- InputBuffer Methods
/**
* Write some bytes.
*
* @return number of bytes written by the filter
*/
@Override
public int doRead(ByteChunk chunk, Request req) throws IOException {
read = true;
return -1;
}
// ---------------------------------------------------- InputFilter Methods
/**
* Set the associated request.
*/
@Override
public void setRequest(Request request) {
// NOOP: Request isn't used so ignore it
}
/**
* Set the next buffer in the filter pipeline.
*/
@Override
public void setBuffer(InputBuffer buffer) {
// NOOP: No body to read
}
/**
* Make the filter ready to process the next request.
*/
@Override
public void recycle() {
read = false;
}
/**
* Return the name of the associated encoding; Here, the value is
* "void".
*/
@Override
public ByteChunk getEncodingName() {
return ENCODING;
}
/**
* End the current request. It is acceptable to write extra bytes using
* buffer.doWrite during the execution of this method.
*
* @return Should return 0 unless the filter does some content length
* delimitation, in which case the number is the amount of extra bytes or
* missing bytes, which would indicate an error.
* Note: It is recommended that extra bytes be swallowed by the filter.
*/
@Override
public long end() throws IOException {
return 0;
}
@Override
public int available() {
if (read) {
return 0;
} else {
return 1;
}
}
@Override
public boolean isFinished() {
return read;
}
}