org.chwf.servlet
Class ServletUtils

java.lang.Object
  |
  +--org.chwf.servlet.ServletUtils

public class ServletUtils

extends java.lang.Object

Class with utility methods for servlets and JSP.

Author:

Paul Strack

Field Summary

static int	EVAL_BODY_TAG BodyTag.EVAL_BODY_TAG.
static java.lang.String	EXCEPTION_CACHE_NAME The name used to cache errors.

Constructor Summary

ServletUtils()

Method Summary

static void	cacheError(javax.servlet.http.HttpServletRequest request, java.lang.Throwable error) Cached an error in the request.
static java.lang.String	encode(java.lang.String value) Place holder to deal with deprecated java.net.URLEncoder.encode() in JDK 1.4.
static void	forward(javax.servlet.ServletRequest request, javax.servlet.ServletResponse response, java.lang.String uri) Forward to the indicated URI.
static java.lang.StringBuffer	getURLWithQueryString(javax.servlet.http.HttpServletRequest request) Get the URL, as per HttpUtils.getRequestURL(), and append the query string.
static void	include(javax.servlet.ServletRequest request, javax.servlet.ServletResponse response, java.lang.String uri) Include the indicated URI.
static java.lang.Throwable	retrieveError(javax.servlet.http.HttpServletRequest request) Retrieves a cached error from the request.
static void	setPageAttribute(javax.servlet.jsp.PageContext context, java.lang.String key, java.lang.Object value) Utility method to compensate for the "feature" of PageContext that it throws a NullPointerException when setting a null attribute value.

Methods inherited from class java.lang.Object

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

Field Detail

EXCEPTION_CACHE_NAME

public static final java.lang.String EXCEPTION_CACHE_NAME

The name used to cache errors. Identical to PageContext.EXCEPTION.

EVAL_BODY_TAG

public static final int EVAL_BODY_TAG

BodyTag.EVAL_BODY_TAG. Defined to cut down on deprecation warnings.

Constructor Detail

ServletUtils

public ServletUtils()

Method Detail

cacheError

public static void cacheError(javax.servlet.http.HttpServletRequest request,
                              java.lang.Throwable error)

Cached an error in the request.

Parameters:

request - The request.

error - The error.

retrieveError

public static java.lang.Throwable retrieveError(javax.servlet.http.HttpServletRequest request)

Retrieves a cached error from the request.

Parameters:

request - The request.

Returns:

The error.

encode

public static java.lang.String encode(java.lang.String value)

Place holder to deal with deprecated java.net.URLEncoder.encode() in JDK 1.4.

Parameters:

value - The value to encode.

Returns:

The encoded value.

forward

public static void forward(javax.servlet.ServletRequest request,
                           javax.servlet.ServletResponse response,
                           java.lang.String uri)
                    throws javax.servlet.ServletException,
                           java.io.IOException

Forward to the indicated URI.

Parameters:

request - The request.

response - The response.

uri - The target URI.

Throws:

javax.servlet.ServletException - For servlet exceptions, or if the URI is not found

java.io.IOException - For IO exceptions.

include

public static void include(javax.servlet.ServletRequest request,
                           javax.servlet.ServletResponse response,
                           java.lang.String uri)
                    throws javax.servlet.ServletException,
                           java.io.IOException

Include the indicated URI.

Parameters:

request - The request.

response - The response.

uri - The target URI.

Throws:

javax.servlet.ServletException - For servlet exceptions, or if the URI is not found

java.io.IOException - For IO exceptions.

getURLWithQueryString

public static java.lang.StringBuffer getURLWithQueryString(javax.servlet.http.HttpServletRequest request)

Get the URL, as per HttpUtils.getRequestURL(), and append the query string.

Parameters:

request - The request.

Returns:

The absolute request URL with the query string.

setPageAttribute

public static void setPageAttribute(javax.servlet.jsp.PageContext context,
                                    java.lang.String key,
                                    java.lang.Object value)
                             throws java.lang.NullPointerException

Utility method to compensate for the "feature" of PageContext that it throws a NullPointerException when setting a null attribute value. This method call the removeAttribute() method if the value is null. Otherwise it calls setAttribute() as usual. If the key is null, it does nothing.

Parameters:

context - The page context.

key - The key value.

value - The attribute value.

Throws:

java.lang.NullPointerException - If the key is null.