alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Tomcat example source code file (ServletRequest.java)

This example Tomcat source code file (ServletRequest.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Tomcat tags/keywords

bufferedreader, enumeration, enumeration, io, ioexception, ioexception, locale, map, object, object, requestdispatcher, servletinputstream, servletrequest, string, string, util

The Tomcat ServletRequest.java source code

/*
* 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 javax.servlet;

import java.io.BufferedReader;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Locale;
import java.util.Map;



/**
 * Defines an object to provide client request information to a servlet.  The
 * servlet container creates a <code>ServletRequest object and passes
 * it as an argument to the servlet's <code>service method.
 *
 * <p>A ServletRequest object provides data including
 * parameter name and values, attributes, and an input stream.
 * Interfaces that extend <code>ServletRequest can provide
 * additional protocol-specific data (for example, HTTP data is
 * provided by {@link javax.servlet.http.HttpServletRequest}.
 * 
 * @author 	Various
 * @version 	$Version$
 *
 * @see 	javax.servlet.http.HttpServletRequest
 *
 */

public interface ServletRequest {




    /**
     *
     * Returns the value of the named attribute as an <code>Object,
     * or <code>null if no attribute of the given name exists. 
     *
     * <p> Attributes can be set two ways.  The servlet container may set
     * attributes to make available custom information about a request.
     * For example, for requests made using HTTPS, the attribute
     * <code>javax.servlet.request.X509Certificate can be used to
     * retrieve information on the certificate of the client.  Attributes
     * can also be set programatically using 
     * {@link ServletRequest#setAttribute}.  This allows information to be
     * embedded into a request before a {@link RequestDispatcher} call.
     *
     * <p>Attribute names should follow the same conventions as package
     * names. This specification reserves names matching <code>java.*,
     * <code>javax.*, and sun.*. 
     *
     * @param name	a <code>String specifying the name of 
     *			the attribute
     *
     * @return		an <code>Object containing the value 
     *			of the attribute, or <code>null if
     *			the attribute does not exist
     *
     */

    public Object getAttribute(String name);
    
    

    /**
     * Returns an <code>Enumeration containing the
     * names of the attributes available to this request. 
     * This method returns an empty <code>Enumeration
     * if the request has no attributes available to it.
     * 
     *
     * @return		an <code>Enumeration of strings 
     *			containing the names 
     * 			of the request's attributes
     *
     */

    public Enumeration getAttributeNames();
    
    
    
    
    /**
     * Returns the name of the character encoding used in the body of this
     * request. This method returns <code>null if the request
     * does not specify a character encoding
     * 
     *
     * @return		a <code>String containing the name of 
     *			the character encoding, or <code>null
     *			if the request does not specify a character encoding
     *
     */

    public String getCharacterEncoding();

 /**
     * Overrides the name of the character encoding used in the body of this
     * request. This method must be called prior to reading request parameters
     * or reading input using getReader().
     * 
     *
     * @param env	a <code>String containing the name of 
     *			the character encoding.
     * @throws		java.io.UnsupportedEncodingException if this is not a valid encoding
     */

    public void setCharacterEncoding(String env) throws java.io.UnsupportedEncodingException;

    
    
    
    
    /**
     * Returns the length, in bytes, of the request body 
     * and made available by the input stream, or -1 if the
     * length is not known. For HTTP servlets, same as the value
     * of the CGI variable CONTENT_LENGTH.
     *
     * @return		an integer containing the length of the 
     * 			request body or -1 if the length is not known
     *
     */

    public int getContentLength();
    
    
    

    /**
     * Returns the MIME type of the body of the request, or 
     * <code>null if the type is not known. For HTTP servlets, 
     * same as the value of the CGI variable CONTENT_TYPE.
     *
     * @return		a <code>String containing the name 
     *			of the MIME type of 
     * 			the request, or null if the type is not known
     *
     */

    public String getContentType();
    
    
    

    /**
     * Retrieves the body of the request as binary data using
     * a {@link ServletInputStream}.  Either this method or 
     * {@link #getReader} may be called to read the body, not both.
     *
     * @return			a {@link ServletInputStream} object containing
     * 				the body of the request
     *
     * @exception IllegalStateException  if the {@link #getReader} method
     * 					 has already been called for this request
     *
     * @exception IOException    	if an input or output exception occurred
     *
     */

    public ServletInputStream getInputStream() throws IOException; 
     
    
    

    /**
     * Returns the value of a request parameter as a <code>String,
     * or <code>null if the parameter does not exist. Request parameters
     * are extra information sent with the request.  For HTTP servlets,
     * parameters are contained in the query string or posted form data.
     *
     * <p>You should only use this method when you are sure the
     * parameter has only one value. If the parameter might have
     * more than one value, use {@link #getParameterValues}.
     *
     * <p>If you use this method with a multivalued
     * parameter, the value returned is equal to the first value
     * in the array returned by <code>getParameterValues.
     *
     * <p>If the parameter data was sent in the request body, such as occurs
     * with an HTTP POST request, then reading the body directly via {@link
     * #getInputStream} or {@link #getReader} can interfere
     * with the execution of this method.
     *
     * @param name 	a <code>String specifying the 
     *			name of the parameter
     *
     * @return		a <code>String representing the 
     *			single value of the parameter
     *
     * @see 		#getParameterValues
     *
     */

    public String getParameter(String name);
    
    
    

    /**
     *
     * Returns an <code>Enumeration of String
     * objects containing the names of the parameters contained
     * in this request. If the request has 
     * no parameters, the method returns an 
     * empty <code>Enumeration. 
     *
     * @return		an <code>Enumeration of String
     *			objects, each <code>String containing
     * 			the name of a request parameter; or an 
     *			empty <code>Enumeration if the
     *			request has no parameters
     *
     */
     
    public Enumeration getParameterNames();
    
    
    

    /**
     * Returns an array of <code>String objects containing 
     * all of the values the given request parameter has, or 
     * <code>null if the parameter does not exist.
     *
     * <p>If the parameter has a single value, the array has a length
     * of 1.
     *
     * @param name	a <code>String containing the name of 
     *			the parameter whose value is requested
     *
     * @return		an array of <code>String objects 
     *			containing the parameter's values
     *
     * @see		#getParameter
     *
     */

    public String[] getParameterValues(String name);
 
    /** Returns a java.util.Map of the parameters of this request.
     * Request parameters
     * are extra information sent with the request.  For HTTP servlets,
     * parameters are contained in the query string or posted form data.
     *
     * @return an immutable java.util.Map containing parameter names as 
     * keys and parameter values as map values. The keys in the parameter
     * map are of type String. The values in the parameter map are of type
     * String array.
     *
     */

    public Map getParameterMap();
    
    

    /**
     * Returns the name and version of the protocol the request uses
     * in the form <i>protocol/majorVersion.minorVersion, for 
     * example, HTTP/1.1. For HTTP servlets, the value
     * returned is the same as the value of the CGI variable 
     * <code>SERVER_PROTOCOL.
     *
     * @return		a <code>String containing the protocol 
     *			name and version number
     *
     */
    
    public String getProtocol();
    
    
    

    /**
     * Returns the name of the scheme used to make this request, 
     * for example,
     * <code>http, https, or ftp.
     * Different schemes have different rules for constructing URLs,
     * as noted in RFC 1738.
     *
     * @return		a <code>String containing the name 
     *			of the scheme used to make this request
     *
     */

    public String getScheme();
    
    
    

    /**
     * Returns the host name of the server to which the request was sent.
     * It is the value of the part before ":" in the <code>Host
     * header value, if any, or the resolved server name, or the server IP address.
     *
     * @return		a <code>String containing the name 
     *			of the server
     */

    public String getServerName();
    
    
    

    /**
     * Returns the port number to which the request was sent.
     * It is the value of the part after ":" in the <code>Host
     * header value, if any, or the server port where the client connection
     * was accepted on.
     *
     * @return		an integer specifying the port number
     *
     */

    public int getServerPort();
    
    
    
    /**
     * Retrieves the body of the request as character data using
     * a <code>BufferedReader.  The reader translates the character
     * data according to the character encoding used on the body.
     * Either this method or {@link #getInputStream} may be called to read the
     * body, not both.
     * 
     *
     * @return					a <code>BufferedReader
     *						containing the body of the request	
     *
     * @exception UnsupportedEncodingException 	if the character set encoding
     * 						used is not supported and the 
     *						text cannot be decoded
     *
     * @exception IllegalStateException   	if {@link #getInputStream} method
     * 						has been called on this request
     *
     * @exception IOException  			if an input or output exception occurred
     *
     * @see 					#getInputStream
     *
     */

    public BufferedReader getReader() throws IOException;
    
    
    

    /**
     * Returns the Internet Protocol (IP) address of the client 
     * or last proxy that sent the request.
     * For HTTP servlets, same as the value of the 
     * CGI variable <code>REMOTE_ADDR.
     *
     * @return		a <code>String containing the 
     *			IP address of the client that sent the request
     *
     */
    
    public String getRemoteAddr();
    
    
    

    /**
     * Returns the fully qualified name of the client
     * or the last proxy that sent the request.
     * If the engine cannot or chooses not to resolve the hostname 
     * (to improve performance), this method returns the dotted-string form of 
     * the IP address. For HTTP servlets, same as the value of the CGI variable 
     * <code>REMOTE_HOST.
     *
     * @return		a <code>String containing the fully 
     *			qualified name of the client
     *
     */

    public String getRemoteHost();
    
    
    

    /**
     *
     * Stores an attribute in this request.
     * Attributes are reset between requests.  This method is most
     * often used in conjunction with {@link RequestDispatcher}.
     *
     * <p>Attribute names should follow the same conventions as
     * package names. Names beginning with <code>java.*,
     * <code>javax.*, and com.sun.*, are
     * reserved for use by Sun Microsystems.
     *<br> If the object passed in is null, the effect is the same as
     * calling {@link #removeAttribute}.
     * <br> It is warned that when the request is dispatched from the
     * servlet resides in a different web application by
     * <code>RequestDispatcher, the object set by this method
     * may not be correctly retrieved in the caller servlet.
     *
     *
     * @param name			a <code>String specifying 
     *					the name of the attribute
     *
     * @param o				the <code>Object to be stored
     *
     */

    public void setAttribute(String name, Object o);
    
    
    

    /**
     *
     * Removes an attribute from this request.  This method is not
     * generally needed as attributes only persist as long as the request
     * is being handled.
     *
     * <p>Attribute names should follow the same conventions as
     * package names. Names beginning with <code>java.*,
     * <code>javax.*, and com.sun.*, are
     * reserved for use by Sun Microsystems.
     *
     *
     * @param name			a <code>String specifying 
     *					the name of the attribute to remove
     *
     */

    public void removeAttribute(String name);
    
    
    

    /**
     *
     * Returns the preferred <code>Locale that the client will 
     * accept content in, based on the Accept-Language header.
     * If the client request doesn't provide an Accept-Language header,
     * this method returns the default locale for the server.
     *
     *
     * @return		the preferred <code>Locale for the client
     *
     */

    public Locale getLocale();
    
    
    

    /**
     *
     * Returns an <code>Enumeration of Locale objects
     * indicating, in decreasing order starting with the preferred locale, the
     * locales that are acceptable to the client based on the Accept-Language
     * header.
     * If the client request doesn't provide an Accept-Language header,
     * this method returns an <code>Enumeration containing one 
     * <code>Locale, the default locale for the server.
     *
     *
     * @return		an <code>Enumeration of preferred 
     *                  <code>Locale objects for the client
     *
     */

    public Enumeration getLocales();
    
    
    

    /**
     *
     * Returns a boolean indicating whether this request was made using a
     * secure channel, such as HTTPS.
     *
     *
     * @return		a boolean indicating if the request was made using a
     *                  secure channel
     *
     */

    public boolean isSecure();
    
    
    

    /**
     *
     * Returns a {@link RequestDispatcher} object that acts as a wrapper for
     * the resource located at the given path.  
     * A <code>RequestDispatcher object can be used to forward
     * a request to the resource or to include the resource in a response.
     * The resource can be dynamic or static.
     *
     * <p>The pathname specified may be relative, although it cannot extend
     * outside the current servlet context.  If the path begins with 
     * a "/" it is interpreted as relative to the current context root.  
     * This method returns <code>null if the servlet container
     * cannot return a <code>RequestDispatcher.
     *
     * <p>The difference between this method and {@link
     * ServletContext#getRequestDispatcher} is that this method can take a
     * relative path.
     *
     * @param path      a <code>String specifying the pathname
     *                  to the resource. If it is relative, it must be
     *                  relative against the current servlet.
     *
     * @return          a <code>RequestDispatcher object
     *                  that acts as a wrapper for the resource
     *                  at the specified path, or <code>null
     *                  if the servlet container cannot return a
     *                  <code>RequestDispatcher
     *
     * @see             RequestDispatcher
     * @see             ServletContext#getRequestDispatcher
     *
     */

    public RequestDispatcher getRequestDispatcher(String path);
    
    
    

    /**
     * 
     * @deprecated 	As of Version 2.1 of the Java Servlet API,
     * 			use {@link ServletContext#getRealPath} instead.
     *
     */

    public String getRealPath(String path);
    
    
    /**
     * Returns the Internet Protocol (IP) source port of the client
     * or last proxy that sent the request.
     *
     * @return	an integer specifying the port number
     *
     * @since 2.4
     */    
    public int getRemotePort();


    /**
     * Returns the host name of the Internet Protocol (IP) interface on
     * which the request was received.
     *
     * @return	a <code>String containing the host
     *		name of the IP on which the request was received.
     *
     * @since 2.4
     */
    public String getLocalName();

    /**
     * Returns the Internet Protocol (IP) address of the interface on
     * which the request  was received.
     *
     * @return	a <code>String containing the
     *		IP address on which the request was received. 
     *
     * @since 2.4
     *
     */       
    public String getLocalAddr();


    /**
     * Returns the Internet Protocol (IP) port number of the interface
     * on which the request was received.
     *
     * @return an integer specifying the port number
     *
     * @since 2.4
     */
    public int getLocalPort();

}

Other Tomcat examples (source code examples)

Here is a short list of links related to this Tomcat ServletRequest.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.