servletrequest.java

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// ServletRequest - this interface represents a servlet request
//
// API based on documentation from JavaSoft.
//
// Copyright (C) 1996,1998 by Jef Poskanzer <[e-mail]>. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE.
//
// Visit the ACME Labs Java page for up-to-date versions of this and other
// fine Java utilities: http://www.acme.com/java/

package Acme.Serve.servlet;

/// This interface represents a servlet request.
// <P>
// This is taken from JavaSoft's Servlet API documentation.
// <P>
// <A HREF="/resources/classes/Acme/Serve/servlet/ServletRequest.java">Fetch the software.</A><BR>
// <A HREF="/resources/classes/Acme.tar.gz">Fetch the entire Acme package.</A>
// <P>
// @see Acme.Serve.servlet.Servlet

import java.io.*;
import java.util.*;

public interface ServletRequest
    {

    /// Returns the size of the request entity data, or -1 if not known.
    // Same as the CGI variable CONTENT_LENGTH.
    public int getContentLength();

    /// Returns the MIME type of the request entity data, or null if
    // not known.
    // Same as the CGI variable CONTENT_TYPE.
    public String getContentType();

    /// Returns the protocol and version of the request as a string of
    // the form <protocol>/<major version>.<minor version>.
    // Same as the CGI variable SERVER_PROTOCOL.
    public String getProtocol();

    /// Returns the scheme of the URL used in this request, for example
    // "http", "https", or "ftp".  Different schemes have different rules
    // for constructing URLs, as noted in RFC 1738.  The URL used to create
    // a request may be reconstructed using this scheme, the server name
    // and port, and additional information such as URIs. 
    public String getScheme();

    /// Returns the host name of the server as used in the <host> part of
    // the request URI.
    // Same as the CGI variable SERVER_NAME.
    public String getServerName();

    /// Returns the port number on which this request was received as used in
    // the <port> part of the request URI.
    // Same as the CGI variable SERVER_PORT.
    public int getServerPort();

    /// Returns the IP address of the agent that sent the request.
    // Same as the CGI variable REMOTE_ADDR.
    public String getRemoteAddr();

    /// Returns the fully qualified host name of the agent that sent the
    // request.
    // Same as the CGI variable REMOTE_HOST.
    public String getRemoteHost();

    /// Applies alias rules to the specified virtual path and returns the
    // corresponding real path, or null if the translation can not be
    // performed for any reason.  For example, an HTTP servlet would
    // resolve the path using the virtual docroot, if virtual hosting is
    // enabled, and with the default docroot otherwise.  Calling this
    // method with the string "/" as an argument returns the document root.
    public String getRealPath( String path );

    /// Returns an input stream for reading request data.
    // @exception IllegalStateException if getReader has already been called
    // @exception IOException on other I/O-related errors
    public ServletInputStream getInputStream() throws IOException;

    /// Returns a buffered reader for reading request data.
    // @exception UnsupportedEncodingException if the character set encoding isn't supported
    // @exception IllegalStateException if getInputStream has already been called
    // @exception IOException on other I/O-related errors
    public BufferedReader getReader();

    /// Returns a string containing the value of the specified parameter,
    // or null if the parameter does not exist. 
    public String getParameter( String name );

    /// Returns the values of the specified parameter for the request as an
    // array of strings, or null if the named parameter does not exist.
    public String[] getParameterValues( String name );

    /// Returns the parameter names for this request.
    public Enumeration getParameterNames();

    /// Returns the value of the named attribute of the request, or null if
    // the attribute does not exist.  This method allows access to request
    // information not already provided by the other methods in this interface.
    public Object getAttribute( String name );

    }