student.web

Class WebUtilities

java.lang.Object

student.web.WebUtilities

public class WebUtilities
extends Object

This class provides static utility methods that streamline some web-related operations, and also that provide useful services for CloudSpace-based programs.

Version:

$Revision: 1.4 $, $Date: 2011/02/18 20:38:49 $

Author:

Stephen Edwards, Last changed by $Author: stedwar2 $

Method Summary

Modifier and Type	Method and Description
static String	getCurrentPageName() Retrieve the name of the current ZHTML file being shown by a CloudSpace web application, such as "index.zhtml" or "lab02.zhtml".
static String	getCurrentPagePath() Retrieve the relative path name of the current ZHTML file being shown by a CloudSpace web application, such as "/Fall09/mypid/index.zhtml" or "/Fall09/mypid/lab02/lab02.zhtml".
static String	getPageParameter(String name) Get a parameter passed to this web page in the query part of the URL.
static void	showWebPage(String url) Cause a CloudSpace web application to show a different web page in the user's web browser.
static String	urlDecode(String content) Decodes a string extracted from a URL parameter.
static String	urlEncode(String content) Encodes a string for use in a URL.
static URL	urlFor(String url) Creates a URL object from a string, without throwing declared exceptions.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

urlEncode

public static String urlEncode(String content)

Encodes a string for use in a URL. This operation wraps the behavior of URLEncoder.encode(String,String), using a UTF-8 encoding and turning any exceptions into RuntimeExceptions.

Parameters:

content - The string to encode

Returns:

The URL-encoded version of the parameter

urlDecode

public static String urlDecode(String content)

Decodes a string extracted from a URL parameter. This operation wraps the behavior of URLDecoder.decode(String,String), using a UTF-8 encoding and turning any exceptions into RuntimeExceptions.

Parameters:

content - The string to decode

Returns:

The URL-decoded version of the parameter

urlFor

public static URL urlFor(String url)

Creates a URL object from a string, without throwing declared exceptions. This wrapper simplifies creation of URL objects in student code by eliminating the need for explicit try/catch blocks if you just want to create a new URL object.

Parameters:

url - The url as a string

Returns:

The new URL object for the given address

showWebPage

public static void showWebPage(String url)

Cause a CloudSpace web application to show a different web page in the user's web browser.

Parameters:

url - The URL of the new web page to show in the user's browser.

getCurrentPageName

public static String getCurrentPageName()

Retrieve the name of the current ZHTML file being shown by a CloudSpace web application, such as "index.zhtml" or "lab02.zhtml".

Returns:

The name of the current ZHTML file, without any directory component, or "" if there is none.

getCurrentPagePath

public static String getCurrentPagePath()

Retrieve the relative path name of the current ZHTML file being shown by a CloudSpace web application, such as "/Fall09/mypid/index.zhtml" or "/Fall09/mypid/lab02/lab02.zhtml".

Returns:

The name path to the current ZHTML file, or "" if there is none.

getPageParameter

public static String getPageParameter(String name)

Get a parameter passed to this web page in the query part of the URL. This method only works in a running CloudSpace web application.

Parameters:

name - The name of the parameter to retrieve.

Returns:

The parameter's value on the current page, or null if there is none.