Java Servlet API 4.0.1 Source Code Files are important if you want to compile them with different JDK releases.

You can get Java Servlet API 4.0.1 Source Code Files from Servlet API Maven Website in the "4.0.1/" folder.

You can also browse Java Servlet API 4.0.1 Source Code files below:

⏎ javax/servlet/ServletInputStream.java

/*
 * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved.
 * Copyright 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.
 */

package javax.servlet;

import java.io.InputStream;
import java.io.IOException;

/**
 * 
 * Provides an input stream for reading binary data from a client
 * request, including an efficient <code>readLine</code> method
 * for reading data one line at a time. With some protocols, such
 * as HTTP POST and PUT, a <code>ServletInputStream</code>
 * object can be used to read data sent from the client.
 *
 * <p>A <code>ServletInputStream</code> object is normally retrieved via
 * the {@link ServletRequest#getInputStream} method.
 *
 *
 * <p>This is an abstract class that a servlet container implements.
 * Subclasses of this class
 * must implement the <code>java.io.InputStream.read()</code> method.
 *
 *
 * @author 	Various
 *
 * @see		ServletRequest 
 *
 */

public abstract class ServletInputStream extends InputStream {



    /**
     * Does nothing, because this is an abstract class.
     *
     */

    protected ServletInputStream() { }

  
  
    
    /**
     *
     * Reads the input stream, one line at a time. Starting at an
     * offset, reads bytes into an array, until it reads a certain number
     * of bytes or reaches a newline character, which it reads into the
     * array as well.
     *
     * <p>This method returns -1 if it reaches the end of the input
     * stream before reading the maximum number of bytes.
     *
     *
     *
     * @param b 		an array of bytes into which data is read
     *
     * @param off 		an integer specifying the character at which
     *				this method begins reading
     *
     * @param len		an integer specifying the maximum number of 
     *				bytes to read
     *
     * @return			an integer specifying the actual number of bytes 
     *				read, or -1 if the end of the stream is reached
     *
     * @exception IOException	if an input or output exception has occurred
     *
     */
    public int readLine(byte[] b, int off, int len) throws IOException {

	if (len <= 0) {
	    return 0;
	}
	int count = 0, c;

	while ((c = read()) != -1) {
	    b[off++] = (byte)c;
	    count++;
	    if (c == '\n' || count == len) {
		break;
	    }
	}
	return count > 0 ? count : -1;
    }


    /**
     * Returns true when all the data from the stream has been read else
     * it returns false.
     *
     * @return <code>true</code> when all data for this particular request
     *  has been read, otherwise returns <code>false</code>.
     *
     * @since Servlet 3.1
     */
    public abstract boolean isFinished();

    /**
     * Returns true if data can be read without blocking else returns
     * false.
     *
     * @return <code>true</code> if data can be obtained without blocking,
     *  otherwise returns <code>false</code>.
     *
     * @since Servlet 3.1
     */
    public abstract boolean isReady();

    /**
     * Instructs the <code>ServletInputStream</code> to invoke the provided
     * {@link ReadListener} when it is possible to read
     *
     * @param readListener the {@link ReadListener} that should be notified
     *  when it's possible to read.
     *
     * @exception IllegalStateException if one of the following conditions is true
     * <ul>
     * <li>the associated request is neither upgraded nor the async started
     * <li>setReadListener is called more than once within the scope of the same request.
     * </ul>
     *
     * @throws NullPointerException if readListener is null
     *
     * @since Servlet 3.1

     */
    public abstract void setReadListener(ReadListener readListener);
}

⏎ javax/servlet/ServletInputStream.java

Or download all of them as a single archive file:

File name: javax.servlet-api-4.0.1-sources.jar
File size: 203006 bytes
Release date: 2018-04-20
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