WAS v8.5 > Reference > Custom properties

Web container custom properties


Overview

We can configure name-value pairs of data, where the name is a property key and the value is a string value used to set internal system configuration properties. Defining a new property enables you to configure a setting beyond that which is available in the dmgr console. The following is a list of some of the available web container custom properties. To specify web container custom properties:

Restart the appserver after saving any change..


Custom properties


BodyContentBuffSize

The size of the body content buffer for a JSP file can affect the performance of some applications. By default, the body content buffer size is 512 bytes. However, we can use the BodyContentBuffSize custom property to set a different buffer value.

Name Default
BodyContentBuffSize 512


com.ibm.ws.jsf.disablealternatefacesconfigsearch

Disables MyFaces searching for META-INF/*.faces-config.xml for all web applications on a server.

Name Default
com.ibm.ws.jsf.disablealternatefacesconfigsearch false


com.ibm.ws.jsp.enableDefaultIsELIgnoredInTag

Typically Expression Language (EL) expressions in tag files get evaluated before the tag files a JavaServer Page (JSP) is compiled. However, under certain conditions these EL expressions in a tag file do not get evaluated if the <el-ignored> attribute is set to true.

To ensure that EL expressions are always evaluated, set the com.ibm.ws.jsp.enableDefaultIsELIgnoredInTag custom property to true. The default value for this property is false.

Name Default
com.ibm.ws.jsp.enableDefaultIsELIgnoredInTag false


com.ibm.ws.jsp.expressionreturnemptystring

Enable you to indicate whether you want the JSP container to return an empty string or null for unset values in an expression.

An expression, such as the following expression, can return a value of null when testValue is null in the testBean:

Some applications expect an empty string to be returned in these situations rather than the value of null. If the applications you are running expect an empty string to be returned, add this custom property to the web container settings and set the property to true.

Name Default
com.ibm.ws.jsp.expressionreturnemptystring false


com.ibm.ws.jsp.getWriterOnEmptyBuffer

The dynamic cache service uses flushes to determine when one cacheable web fragment, such as a JSP include or a c:import, ends and the next web fragment begins. If you set the com.ibm.wsspi.jsp.usecdatatrim custom property to true for the JSP engine, all of the white space and extra lines in the generated Java code are stripped out. In this situation, there might not be any content to write before the first flush. If the generated Java code contains text or other code before the first flush then normal dynamic cache service processing occurs.

If you set the com.ibm.wsspi.jsp.usecdatatrim custom property to true, and are using the dynamic cache service, you must also set the com.ibm.ws.jsp.getWriterOnEmptyBuffer custom property to true. This custom property requires the JSP Engine to call the flush function when it reaches the end of the first cachable web fragments even if there is not any data to flush. The default value for this property is false.

Name Default
com.ibm.ws.jsp.getWriterOnEmptyBuffer false


com.ibm.ws.jsp.limitBuffer

The body content buffer size of the tag bodies for a JSP file are reused to optimize performance. If the size of a tag body increases beyond the default body content buffer size, the buffer is resized to accommodate the tag body. However, the buffer is not reset to the default size after serving a request. As a result, the heap memory used by org.apache.jasper.runtime.BodyContentImpl implementation might increase over time. We can configure the body content buffer size by setting an integer value for the BodyContentBuffSize custom property. For more information, see BodyContentBuffSize.

Use the com.ibm.ws.jsp.limitBuffer custom property to deallocate large body content buffer sizes and create a buffer with the default buffer size.

Name Default
com.ibm.ws.jsp.limitBuffer false


com.ibm.ws.jsp.throwExceptionForAddELResolver

Set the com.ibm.ws.jsp.throwExceptionForAddELResolver property to true if we do not want to allow an ELResolver to be registered from a servlet or a filter after the application has received a request from the client. When true, an IllegalStateException is thrown as specified by the JSP (Java Server Pages) specification for addELResolver() method of the JspApplicationContext interface.

The default value for this property is false.

Name Default
com.ibm.ws.jsp.throwExceptionForAddELResolver false


com.ibm.ws.webcontainer.AllowQueryParamWithNoEqual

If the query parameter in a URL only contains the string "name" instead of the expected "name=value" format, the server returns the value of request.getParameter("name") query as null.

When true, if the query parameter in a URL only contains the string "name", the server returns an empty string as the value for the request.getParameter("name") query

Name Default
com.ibm.ws.webcontainer.AllowQueryParamWithNoEqual false


com.ibm.ws.webcontainer.asyncmaxsizetaskpool

This custom property specifies the maximum task queue size which is used to hold the dispatched asynchronous servlet.

Name Default Value
com.ibm.ws.webcontainer.asyncmaxsizetaskpool 5000


com.ibm.ws.webcontainer.asyncpurgeinterval

This custom property specifies the interval which the webcontainer should purge the task queue to release the resource of the canceled tasks.

Name Default Value
com.ibm.ws.webcontainer.asyncpurgeinterval 30000


com.ibm.ws.webcontainer.channelwritetype

By default, the web container uses asynchronous writes to write response data in chunks up to the response buffer size. For larger responses that are greater than the response buffer size, the web container continues to buffer response data into memory while waiting for an asynchronous write of a response data chunk to complete. This process can result in part of a large response held in memory, which can lead to high memory usage and potentially an out of memory error. An application server hang might also occur when a server is simultaneously processing more requests than web container-defined threads.

If the com.ibm.ws.webcontainer.channelwritetype property is set to sync, synchronous writing is used, otherwise asynchronous writing is used by default. With synchronous writing, response data are written synchronously in chunks of up to the value of responsebuffersize and no response data are buffered into memory while waiting for a synchronous write of a response data chunk to complete. As a result, the approximate maximum amount of response data that is held in memory is equal to the responsebuffersize multiplied by the number of web container threads. Maximum number of requests that can be processed simultaneously by the web container is limited by the number of web container threads. Additional requests are queued, waiting for a request that is in process to complete.

The responsebuffersize web container custom property defines the maximum amount of response data written by the web container in a single chunk, and is 32k by default. As a result, it is used to change the number of writes needed by the web container to send complete response data. However, if an application flushes response data, any response data held by the web container is immediately written irrespective of the responsebuffersize.

Use the following name-value pair to write chunks of data using synchronous writes.

Name Default
com.ibm.ws.webcontainer.channelwritetype async


com.ibm.ws.webcontainer.checkEDRinGetRealPath

The ServletContext.getRealPath() Java Servlet API does not return the correct path for a requested resource when the resource exists in an extendedDocumentRoot path and does not exist in the installed application path. If you want the ServletContext.getRealPath() Java Servlet API to look for the requested resource in the extendedDocumentRoot path if the resource is not found in the installed application path, set the com.ibm.ws.webcontainer.checkEDRinGetRealPath custom property to true.

When true, and the requested resource is also not found in the extendedDocumentRoot path, a null value is returned.

Name Default
com.ibm.ws.webcontainer.checkEDRinGetRealPath false


com.ibm.ws.webcontainer.copyattributeskeyset

This custom property addresses a situation where the request.getAttributeNames method returns a list of values. If a servlet modifies the list using the request.removeAttribute method, subsequent calls to the nextElement method causes a java.util.ConcurrentModificationException exception. To enable a servlet to modify the list, set the com.ibm.ws.webcontainer.copyattributeskeyset custom property to true. When you set this custom property to true, a copy of the list of attributes is returned, which enables the servlet to modify the list without resulting in a java.util.ConcurrentModificationException exception when the nextElement method is called.

Name Default
com.ibm.ws.webcontainer.copyattributeskeyset false


com.ibm.ws.webcontainer.disableSetCharacterEncodingAfterParametersRead

The web container processes a setCharacterEncoding(String) method of the ServletRequest API even if it is called after the post data is parsed. According to the Java Servlet Specification, the web container should ignore a setCharacterEncoding(String) method if the method is called after the data is parsed.

If you want the web container to ignore a setCharacterEncoding(String) method if the method is called after the data is parsed, add the com.ibm.ws.webcontainer.disableSetCharacterEncodingAfterParametersRead custom property to the web container configuration settings and set this property to true.

The default value for this property is false.

Name Default
com.ibm.ws.webcontainer.disableSetCharacterEncodingAfterParametersRead false


com.ibm.ws.webcontainer.disableSystemAppGlobalListenerLoading

If a system application is the first to start, and the application attempts to load a global listener in a shared library associated with the server classloader, the application does not load that listener and prevents the listener from being loaded or invoked by a later non-system application. Set the com.ibm.ws.webcontainer.disableSystemAppGlobalListenerLoading custom property to true to prevent system applications from loading global listeners. When true, the system application does not attempt to load the global listeners and later non-system applications can load them from a shared library associated with a server class loader.

Name Default
com.ibm.ws.webcontainer.disableSystemAppGlobalListenerLoading false


com.ibm.ws.webcontainer.disablexPoweredBy

When you configure server security, we can turn off the X-Powered-By header if we do not want to reveal which server you are running. Use this custom property to disable the X-Powered-By header, which prevents the header from being sent on the HTTP response. Default is false. However, set this property to true, to disable this header.

Name Default
com.ibm.ws.webcontainer.disablexPoweredBy false


com.ibm.ws.webcontainer.disallowAllFileServing

Use the com.ibm.ws.webcontainer.disallowAllFileServing custom property to disable file serving on all applications on a specific application server.

We can enable file serving on a global level across a given application server using the fileServingEnabled custom property. However, the fileServingEnabled property is overridden by the specific deployment information of each application. Therefore, the current fileServingEnabled custom property only applies as a backup in case an application does not define the fileServingEnabled setting itself.

To globally override this setting on a specific application server to prevent the application server from serving static files regardless of their individual deployment settings, set the com.ibm.ws.webcontainer.disallowAllFileServing web container custom property to true using the following name-value pair.

Name Default
com.ibm.ws.webcontainer.disallowAllFileServing false


com.ibm.ws.webcontainer.disallowserveservletsbyclassname

By default, users can access servlets by their class name instead of an alias. For example, to call the servlet defined in the com.ibm.itso.MyServlet, specify a URI, such as...

We want to disable this feature. Even if servlet URLs are secured, a malicious attacker might be able to bypass the normal URL-based security.

To disallow direct access to servlets, go to...

...and set to true...

Name Default
com.ibm.ws.webcontainer.disallowserveservletsbyclassname false


com.ibm.ws.webcontainer.discernUnavailableServlet

Typically, when the web container receives an UnavailableException, it cannot determine whether the exception was issued from a servlet or a dispatched resource. Therefore, the web container automatically marks the servlet unavailable even if it is the dispatched resource that is unavailable.

If you are running on v7.0.0.5 or later, and have set the com.ibm.ws.webcontainer.discernUnavailableServlet custom property to true, any UnavailableException that is issued from a dispatched resource is placed in a wrapper. This wrapper enables the web container to determine whether the exception was issued from the servlet or a dispatched resource. If the exception is not issued by the servlet, the web container does not mark the servlet unavailable.

Name Default
com.ibm.ws.webcontainer.discernUnavailableServlet false


com.ibm.ws.webcontainer.dispatcherRethrowSER

The RequestDispatcher propagates the exceptions from the dispatched servlets back to the dispatching servlets. This is a change in behavior from that in previous releases. If we do not want the application to throw exceptions back to the servlet doing the dispatching, add the com.ibm.ws.webcontainer.dispatcherRethrowSER custom property to the settings for the web container and set the property to false.

Name Default
com.ibm.ws.webcontainer.dispatcherRethrowSER true

The com.ibm.ws.webcontainer.dispatcherRethrowSError custom property supersedes the com.ibm.ws.webcontainer.dispatcherRethrowSER custom property. When you enable the com.ibm.ws.webcontainer.dispatcherRethrowSError custom property by setting its value to true, the com.ibm.ws.webcontainer.dispatcherRethrowSER custom property is also set to true.


com.ibm.ws.webcontainer.dispatcherRethrowSError

When a JavaServer Page (JSP) file contains a compilation error, the runtime error is caught and handled directly by the container. Exceptions are not propagated and addressed by the dispatched JSP resource. With the com.ibm.ws.webcontainer.dispatcherRethrowSError custom property, exceptions are propagated back to the dispatched JSP resource.

Name Default
com.ibm.ws.webcontainer.dispatcherRethrowSError false

The com.ibm.ws.webcontainer.dispatcherRethrowSError custom property supersedes the com.ibm.ws.webcontainer.dispatcherRethrowSER custom property. When you enable the com.ibm.ws.webcontainer.dispatcherRethrowSError custom property by setting its value to true, the com.ibm.ws.webcontainer.dispatcherRethrowSER custom property is also set to true.


com.ibm.ws.webcontainer.donotservebyclassname

The com.ibm.ws.webcontainer.donotservebyclassname custom property specifies a list of classes that cannot be served by the class name.

Name Default
com.ibm.ws.webcontainer.donotservebyclassname none


com.ibm.ws.webcontainer.enabledefaultservletrequestpathelements

To correctly map a request to a default servlet, you must determine the proper servlet path and PathInfo values. The following table shows the affects on the Servlet Path and PathInfo values when we set the com.ibm.ws.webcontainer.enabledefaultservletrequestpathelements custom property to a true or false value.

Servlet Path and PathInfo values. Values for Servlet Path and PathInfo

Value Servlet Path value PathInfo value
true Set to the contents of the URI after the Context Path Set to a null value
false (Default) Set to an empty string Set based on the contents of the URI after the Context Path


com.ibm.ws.webcontainer.enableErrorExceptionTypeFirst

When an exception occurs, the Web container searches for an error page to handle that exception. The default searching order is:

  1. Any matching error-code error page
  2. Any matching exception-type error page

The matched error-code page is always returned even if there is also a matching exception type error page defined in web.xml. To have the Web container search and use the exception-type before the error-code, set this property to true.

Name Default
com.ibm.ws.webcontainer.enableErrorExceptionTypeFirst false


com.ibm.ws.webcontainer.enableExactMatchJSecurityCheck

Specify this property to allow the keyword j_security_check to be used as part of the name of a resource.

Typically, if a URI contains the keyword j_security_check the login process is initiated.

Name Default
com.ibm.ws.webcontainer.enableExactMatchJSecurityCheck false


com.ibm.ws.webcontainer.enableJspMappingOverride

When a url-pattern is defined in the jsp-property-group of the web.xml, file, it is typically mapped to, and handled by the JavaServer Page (JSP) engine. If we have applications that must override this mapping so they can handle and serve the JSP content themselves, set the com.ibm.ws.webcontainer.enableJspMappingOverride property to true.

Name Default
com.ibm.ws.webcontainer.enableJspMappingOverride false


com.ibm.ws.webcontainer.enableMultiReadOfPostData

Set the com.ibm.ws.webcontainer.enableMultiReadOfPostData custom property to true to enable multiple reads of post data. When true, the post data can be read multiple times as either an InputStream or Reader, and as parameters.

When the web container is enabled for multiple reads of post data, we can set up an application to complete the following actions if you want that application to re-read post data from the beginning using either an InputStream or Reader:

  1. Obtain the InputStream or Reader
  2. Read the data
  3. Close the InputStrean or Reader

If either the first or third action does not occur, the next read of the post data is not reset to the beginning of that data.

The web container automatically completes this sequence if an application re-reads the post data as parameters.

Name Default
com.ibm.ws.webcontainer.enableMultiReadOfPostData false


com.ibm.ws.webcontainer.extractHostHeaderPort and trusthostheaderport

The getServerPort method relies on the getVirtualPort method of the channel, which returns a port number in the following order:

  1. Port number from the request URL
  2. Port number from the request host header

This order is compliant with HTTP/1.1 RFC but not with the Java Servlet Specification v2.4 API, which requires the port number from the host header to be returned first, if any, or the request URL. The correct returned URL for the above example is: http://ProxyServer:8888.

The web container was modified to return a port number from the host header, if any, or the URL port that accepted the client connection. Set the trusthostheaderport and the com.ibm.ws.webcontainer.extractHostHeaderPort custom property to true to return the port number from the request host header first. For example, set these properties in the web.xml file using: 

trusthostheaderport = true     
com.ibm.ws.webcontainer.extractHostHeaderPort = true

Or we can set these properties as web container custom properties in the dmgr console using the following two sets of name-value pairs:

Name Default
com.ibm.ws.webcontainer.extractHostHeaderPort false
trusthostheaderport false


com.ibm.ws.webcontainer.finishresponseonclose

Use the com.ibm.ws.webcontainer.finishresponseonclose custom property to indicate you want the web container to close a connection when a servlet calls close() on a writer or output stream.

Typically, when a servlet calls close() on a writer or output stream, the web container sends the data that has been written to the writer or output stream to the client, and then waits for the servlet service() method to finish before it closes the connection. This delay might be interpreted as a response completion delay, especially if a servlet service() method does not complete until sometime after the writer or output stream is closed.

Name Default
com.ibm.ws.webcontainer.finishresponseonclose false


com.ibm.ws.webcontainer.ForceDifferentCookiePaths

When you configure an application to use a cookie to track the session, the default path for the cookie is set to the context root of the application. Therefore, the cookie is only sent to requests that are made to this application. To change the default path to be "/" (forward slash), such the cookie is sent to requests for any application in this domain, set the ForceDifferentCookiePaths session manager custom property.

Name Default
com.ibm.ws.webcontainer.ForceDifferentCookiePaths false


com.ibm.ws.webcontainer.HTTPOnlyCookies

The com.ibm.ws.webcontainer.HTTPOnlyCookies custom property provides a level of defense against a client-side script accessing a protected cookie and acquiring its content. When we use this custom property, we can prevent Java scripts that run in a browser from accessing all cookies or a particular list of cookies of your choosing. The HTTPOnly attribute is added to each cookie specified in this custom property and enables protection from client-side script access.

Specifying com.ibm.ws.webcontainer.HTTPOnlyCookies with no operands means the HTTPOnly attribute will NOT be added to any cookie, and any client-side Java script running in a browser can access the content of any cookies.

We can specify the following values for this property:

The following examples illustrate how to specify these two settings: 

com.ibm.ws.webcontainer.HTTPOnlyCookies=*
com.ibm.ws.webcontainer.HTTPOnlyCookies=cookieName1,Account3Cookie,JsessionID

Cookie names used in specifying com.ibm.ws.webcontainer.HTTPOnlyCookies are case-insensitive.

Name Default
com.ibm.ws.webcontainer.HTTPOnlyCookies none


com.ibm.ws.webcontainer.ignoreinjectionfailure

If a resource or EJB injection fails during the servlet initialization process, an error message is written to the server log files. However, the error message is not propagated to the client. In addition, the servlet is put into service and it is not reinitialized until its application is restarted. During this time, if a request is received that references the resource, which previously failed to inject, a NullPointerException exception results. Similarly, this problem can occur during the filter and listener initialization processes.

The com.ibm.ws.webcontainer.ignoreinjectionfailure custom property enables you to specify whether to propagate these error messages and whether to put a servlet into service. By default, the custom property is set to false, which retains the previously described behavior. To enable the propagation of these injection exceptions to the client and to not put the servlet into service, you must leave this custom property set to false.

Name Default
com.ibm.ws.webcontainer.ignoreinjectionfailure false


com.ibm.ws.webcontainer.ignoreInvalidQueryString

When the web container encounters an encoding character in a query string pair not valid, it throws an IllegalArgumentException exception and, by default, ignores the entire query string. In applications where every field in the query string is an essential resource, it might not be desirable to ignore the entire query string. If you set the com.ibm.ws.webcontainer.ignoreInvalidQueryString custom property to true, the web container ignores query string pairs that are not valid and continues to process valid query string pairs.

Name Default
com.ibm.ws.webcontainer.ignoreInvalidQueryString false


com.ibm.ws.webcontainer.IgnoreSessiononStaticFileRequest

The web container accesses a session for the static file requests involving filters. This action can result in a performance degradation, for example, when running with database session persistence. If you set the com.ibm.ws.webcontainer.IgnoreSessiononStaticFileRequest custom property to true, the web container cannot access a session for the static files requests involving filters.

Name Default
com.ibm.ws.webcontainer.IgnoreSessiononStaticFileRequest false

com.ibm.ws.webcontainer.initFilterBeforeInitServlet

Set the com.ibm.ws.webcontainer.initFilterBeforeInitServlet custom property to true to initialize filters before initializing load-on-startup servlets during the startup process for an application.

Both the com.ibm.ws.webcontainer.invokeFilterInitAtStartup property and the com.ibm.ws.webcontainer.initFilterBeforeInitServlet property must be set to true for the filters to be initialized first on application startup

Name Default
com.ibm.ws.webcontainer.initFilterBeforeInitServlet false


com.ibm.ws.webcontainer.invokeFilterInitAtStartup

The com.ibm.ws.webcontainer.invokeFilterInitAtStartup custom property enables the web container to invoke the init method and initialize a filter during the startup process for an application.

Name Default
com.ibm.ws.webcontainer.invokeFilterInitAtStartup false


com.ibm.ws.webcontainer.invokerequestlistenerforfilter

If a web application has defined the listener in the web deployment descriptor xml file, then set the com.ibm.ws.webcontainer.invokerequestlistenerforfilter custom property to true to have ServletRequestListener invoked when a request is about to enter the filter for that web application.

According to the Java Servlet Specification, a ServletRequestListener should be invoked if a request is about to enter the filter for a web application that has defined the listener in the web deployment descriptor xml file.

Name Default
com.ibm.ws.webcontainer.invokerequestlistenerforfilter false


com.ibm.ws.webcontainer.KeepUnreadPostDataAfterResponseSentToClient

This property indicates whether post data is available to read after the client response is completed, following either the completion of a forward request completes, or a return from a sendRedirect. If true, post data is available to read after the client response is completed either after a forward request completes, which is the default behavior, or on a return from a sendRedirect,, which occurs when the com.ibm.ws.webcontainer.SendResponseToClientAsPartOfSendRedirect custom property is set to true. However, setting this property to true requires unread post data to be held in memory until the target resource completes, and increases memory usage.

Name Default
com.ibm.ws.webcontainer.KeepUnreadPostDataAfterResponseSentToClient false


com.ibm.ws.webcontainer.logServletContainerInitializerClassloadingErrors

When examining the classes of an application to see if they match any of the criteria specified by the HandlesTypes annotation of a ServletContainerInitializer, the container might run into class loading problems if one or more of the optional application JAR files are missing. Because the container does not decide whether these types of class loading failures prevent the application from working correctly, it ignores the failures and provides a configuration option that logs them.

Setting this property to true turns on logging.

Name Default
com.ibm.ws.webcontainer.logServletContainerInitializerClassloadingErrors false


com.ibm.ws.webcontainer.mapFiltersToAsterisk

When processing a request, the web container recognizes servlet mappings to "*" as the same as servlet mappings to "/*". To provide the same behavior with filter mapping, set the com.ibm.ws.webcontainer.mapFiltersToAsterisk custom property to true. Setting the com.ibm.ws.webcontainer.mapFiltersToAsterisk custom property to true causes the web container to recognize filter mappings to "*" as a filter mapping to "/*". This custom property is not case-sensitive.

Name Default
com.ibm.ws.webcontainer.mapFiltersToAsterisk false


com.ibm.ws.webcontainer.maxParamPerRequest

We can use this property to change the maximum number of parameters allowed in your inbound requests, based on the applications and environment. Maximum number of parameters allowed per inbound request (GET or POST) defaults to 10000.

We can set this property to -1 if we do not want to limit the number of parameters that can be included in a request.

Name Default
com.ibm.ws.webcontainer.maxParamPerRequest 10000


com.ibm.ws.webcontainer.modifiedFileNotFoundExceptionBehavior

When a file does not exist and is the target of an include or forward operation for a request dispatcher, a FileNotFoundException occurs. When true, this exception is suppressed as well as any logging of the failure. Also, if such a request results in a 404 exception, FFDCs are no longer created. You enable this file not found exception behavior by setting this custom property to true.

Name Default
com.ibm.ws.webcontainer.modifiedFileNotfFoundExceptionBehavior true


com.ibm.ws.webcontainer.ModifiedSinceLaterThanFileTimeStamp

When true, the web container returns a 304 response if the If-Modified-Since timestamp of the requested variant is newer than the timestamp of the target variant.

Name Default
com.ibm.ws.webcontainer.ModifiedSinceLaterThanFileTimeStamp false


com.ibm.ws.webcontainer.normalizerequesturi

Typically, request URI 404 errors do not occur if a request URI is submitted from a browser, because most modern browsers automatically normalizes a request URI before calling WAS. Therefore, by default, the web container does not normalize a request URI before trying to resolve that URI to an application and servlet mapping.

A request URI, that includes /./ or /../ as part of an application context, that has not been normalized, might fail with a 404 error. Similarly, a request URI, that includes /./" or /../ as part of a servlet path, that has not been normalized, fails to match a servlet mapping, which also results in a 404 error, even though the URI is normalized before resolving the URI to a JSP or static file.

We can set the com.ibm.ws.webcontainer.normalizerequesturi custom property to true and the web container normalizes these types of request URIs.

Name Default
com.ibm.ws.webcontainer.normalizerequesturi false


com.ibm.ws.webcontainer.parseUTF8PostData

If the web container attempts to process a request that includes UTF-8 post data not URL encoded, the target resource accesses the post data as parameters. However, the UTF-8 data is not decoded correctly and the result data might be lost.

To resolve this issue, set the com.ibm.ws.webcontainer.parseUTF8PostData custom property to true. When the web container processes parameters, it detects UTF-8 post data not URL encoded and includes the data in the parameter values.

To use this function, set the value to true.

Name Default
com.ibm.ws.webcontainer.parseUTF8PostData false


com.ibm.ws.webcontainer.provideQStringToWelcomeFile

Typically, when a request is initially sent to the context root of the application, the request is forwarded to a welcome file. If a query string is included in an initial request, it is unavailable to the welcome file if you included the request.getQueryString() attribute in the welcome file. However, the query string is available to the welcome file if you included the javax.servlet.forward.query_string attribute in the welcome file.

If use the request.getQueryString() attribute, instead of the javax.servlet.forward.query_string attribute, to make the query string available to the welcome file, add the com.ibm.ws.webcontainer.provideQStringToWelcomeFile custom property to the web container configuration and set the property to true.

Name Default
com.ibm.ws.webcontainer.provideQStringToWelcomeFile false


com.ibm.ws.webcontainer.returnDefaultContextPath

Use the com.ibm.ws.webcontainer.returnDefaultContextPath custom property to return the correct context path when an application is installed on the default context root. For example, when the property is set to true, the context path is set to an empty string for any application that is installed on the default context root.

Data type Default
Boolean False


com.ibm.ws.webcontainer.SendResponseToClientAsPartOfSendRedirect

This property indicates whether a response is completed as part of a a sendRedirect request. If true, a response is completed as part of a sendRedirect request, and any post data associated with the request is not available for a read on return from sendRedirect.

Default is false.

Name Default
com.ibm.ws.webcontainer.SendResponseToClientAsPartOfSendRedirect false


com.ibm.ws.webcontainer.SendResponseToClientWhenResponseIsComplete

This property indicates whether a response is completed on return from a forward request.

If false, a response is not completed on return from a forward request. Instead, it is delayed until the target resource completes. Post data is available for a read after the forward completes.

Name Default
com.ibm.ws.webcontainer.SendResponseToClientAsPartOfSendRedirect true


com.ibm.ws.webcontainer.setcontenttypebysetheader

When autoResponseEncoding is enabled or when the com.ibm.ws.webcontainer.contentTypeCompatibility property is set, the application server sets the content type of the response using an internal method. To enable setting the content-type using the ServletResponse.setContentType method instead, you need to set the com.ibm.ws.webcontainer.setcontenttypebysetheader custom property to false.

Name Default
com.ibm.ws.webcontainer.setcontenttypebysetheader true


com.ibm.ws.webcontainer.ServeWelcomeFileFromExtendedDocumentRoot

Typically, the first time the web container handles a request for a static welcome page not a JSP file, the web container does not search the ExtendedDocumentRoot for the welcome file unless the request for that welcome file is fully-qualified. If the request is fully-qualified, the web container serves the welcome file, and the context root of the application displays the welcome file. If the request for the static welcome file is not fully-qualified, the web container returns a 404 error, which indicates the web container did not find the welcome file.

After the web container successfully serves a welcome file, the web container creates a mapping for that welcome file. The web container then uses this mapping to handle future requests for the welcome file, thereby eliminating the need for subsequent requests to be fully-qualified.

If you want the web container to always search an application defined ExtendedDocumentRoot for a welcome file, even if the request is not fully-qualified, we can add the com.ibm.ws.webcontainer.ServeWelcomeFileFromExtendedDocumentRoot custom property to the web container settings, and set this property to true.

Name Default
com.ibm.ws.webcontainer.ServeWelcomeFileFromExtendedDocumentRoot false


com.ibm.ws.webcontainer.ServletDestroyWaitTime

By default, when an application is stopped the web container waits up to 60 seconds for each active request for a resource of that application to complete. We can now define the com.ibm.ws.webcontainer.ServletDestroyWaitTime web container custom property to control the amount of time the web container waits for an active request to complete when the owning application is stopped.

Set the com.ibm.ws.webcontainer.ServletDestroyWaitTime custom property to an integer value, which specifies the number of seconds to wait for a request to complete. Default is 60 seconds.

Name Default
com.ibm.ws.webcontainer.ServletDestroyWaitTime 60


com.ibm.ws.webcontainer.setUnencodedHTMLinsendError

Typically, the web container encodes the specified error messages before formatting them, to prevent Cross-Site Scripting (XSS) attacks on the client if the application does not sanitize these messages. However the Java Servlet Specification for the sendError(int, String) method, indicates the server should create the response to look like an HTML-formatted server error page.

If we do not want the web container to encode the specified error messages before formatting them, add the com.ibm.ws.webcontainer.setUnencodedHTMLinsendError custom property to the web container configuration settings, and set the property to true.

Name Default
com.ibm.ws.webcontainer.setUnencodedHTMLinsendError false


com.ibm.ws.webcontainer.SkipMetaInfResourcesProcessing

The web container searches for static files and JSP (JSP) files in different locations, depending on application configuration. A web fragment comprises a JAR file in an application WEB-INF/lib directory. The JAR might include static resources in a META-INF/resources directory that are defined within the JAR file. To prevent the web container from searching the META-INF/resources directories, set the com.ibm.ws.webcontainer.SkipMetaInfResourcesProcessing web container custom property to true.

The default value for the custom property is false.

Name Default
com.ibm.ws.webcontainer.SkipMetaInfResourcesProcessing false


com.ibm.ws.webcontainer.suppressheadersinrequest

The com.ibm.ws.webcontainer.suppressheadersinrequest custom property can be used to suppress the inclusion of request headers that start with special characters, such as "$" or "_". Some applications do not handle request headers that start with special characters.

The value specified for this custom property is a delimited list of the header prefixes to be suppressed.

Example:

Name Default
com.ibm.ws.webcontainer.suppressheadersinrequest none


com.ibm.ws.webcontainer.suppressHtmlRecursiveErrorOutput

During a recursive error that an application-specified error page cannot handle, the stack trace and error message are output as an HTML page. This information includes class names and program information the application developer does not want expose to the user.

We can set the com.ibm.ws.webcontainer.suppressHtmlRecursiveErrorOutput web container custom property to suppress the HTML output of the error text, without changing the internal logging of the message. Set the custom property com.ibm.ws. webcontainer.suppressHtmlRecursiveErrorOutput to true to disable the HTML output of the error message to the user and present the user with blank page with a 500 error code.

Name Default
com.ibm.ws.webcontainer.suppressHtmlRecursiveErrorOutput false


com.ibm.ws.webcontainer.suppressLastZeroBytePackage

Typically, the last zero byte chunk is used to indicate to a client the end of the response data in a chunked encoded transmission. Some applications use this last zero to determine when the response data is completely received, and they can start processing it. If an error occurs in the application after the response headers are sent, the last chunk of data is still sent to the client. The client might not realize that an error has occurred, and attempt to process incomplete data.

If you set the com.ibm.ws.webcontainer.suppressLastZeroBytePackage custom property to true, if an error occurs in the application after the response headers are sent, the last chunk of data is not sent to the client.

Name Default
com.ibm.ws.webcontainer.suppressLastZeroBytePackage false

com.ibm.ws.webcontainer.suppressLoggingFileNotFoundExceptions

The web container generates a severe error message with a FileNotFoundException stack trace in the JVM logs when a missing file is requested. This might not be a severe error if the wrong file was accidentally requested. Set to true to generate a warning message in the JVM logs instead of a severe error message when a file is not found.

Name Default
com.ibm.ws.webcontainer.suppressLoggingFileNotFoundExceptions false


com.ibm.ws.webcontainer.suppressServletExceptionLogging

If a servlet creates an exception, it is logged to the system console. If we do not want the web container to log servlet-created exceptions, add the com.ibm.ws.webcontainer.suppressServletExceptionLogging custom property to the web container configuration settings, and set the property to true.

Name Default
com.ibm.ws.webcontainer.suppressServletExceptionLogging false


com.ibm.ws.webcontainer.throwMissingJspException

Set the com.ibm.ws.webcontainer.throwMissingJspException custom property to true to create a FileNotFoundException when a resource that is included by a JSP file is missing. If this property is not set to true, an error page displays.

Name Default
com.ibm.ws.webcontainer.throwMissingJspException false

com.ibm.ws.webcontainer.throwpostconstructexception

Set the com.ibm.ws.webcontainer.throwpostconstructexception custom property to true to propagate custom error messages to the error.xhtml file.

For transitioning users: The default value for this custom property has changed from v7.0. In v7.0, the default value is false.trns

Name Default
com.ibm.ws.webcontainer.throwpostconstructexception true

com.ibm.ws.webcontainer.tolerateLocaleMismatchForServingFiles

You might encounter a FileNotFound 404 error from the web container and the request is not served when the following encodings do not match:

For example, if the request is for a double-byte character set (DBCS)-encoded file name and the file system locale is en_US, which is an ISO-8859 encoding, the match fails.

To resolve this issue, set the com.ibm.ws.webcontainer.tolerateLocaleMismatchForServingFiles custom property to true. When you set this custom property, the web container tolerates the mismatch of the file system and requested file name encodings. The web container then serves the request for a valid file.

Name Default
com.ibm.ws.webcontainer.tolerateLocaleMismatchForServingFiles false


com.ibm.ws.webcontainer.webgroupvhostnotfound

Error message SRVE0017W states "Web Group not found: {0}", and error message SRVE0255 states "A WebGroup/Virtual Host to handle {0} has not been defined". These messages might be returned when the application that is called to process the request serviced by IBM WAS is not found. We can use the com.ibm.ws.webcontainer.webgroupvhostnotfound custom property to change the text of these messages to text that is more suitable for the environment.

Name Default
com.ibm.ws.webcontainer.webgroupvhostnotfound

none


com.ibm.ws.webcontainer.xPoweredBy

This custom property enables you to configure the value of the X-Powered-By header, which supplies the implementation information of the server.

Name Default
com.ibm.ws.webcontainer.xPoweredBy Servlet/3.0


com.ibm.wsspi.jsp.convertAttrValueToString

Set the com.ibm.wsspi.jsp.convertAttrValueToString web container custom property to true to convert start and end attributes of the repeat tag to strings before they are used.

Name Default
com.ibm.wsspi.jsp.convertAttrValueToString false


com.ibm.wsspi.jsp.disableElCache

Set the com.ibm.wsspi.jsp.disableElCache web container custom property to true to disable the commons-el expression cache if you are experiencing out of memory conditions because the hash maps are held by the expression evaluator.

Name Default
com.ibm.wsspi.jsp.disableElCache false


com.ibm.wsspi.jsp.disableResourceInjection

The resource injection feature accesses resources in applications differently than it did in earlier versions of the product, and causes the compiled method output to be larger than it was previously. If we have large JSP files that in earlier releases pushed the 65535 byte limit in the translated service method, they might now exceed this limit, causing the compile to fail.

If you encounter this situation, we can either break a large JSP file into smaller JSP files, and use <jsp:include> statements to combine them after they are compiled, or we can add the com.ibm.wsspi.jsp.disableResourceInjection custom property to the web container settings to disable the resource injection function during the JSP translation process. When the com.ibm.wsspi.jsp.disableResourceInjection custom property is set to true, the resource injection function is disabled for all applications.

If you only want to disable the resource injection function for specific applications, we can add the disableResourceInjection JSP attribute to the ibm-web-ext.xmi files for those specific applications.

Name Default
com.ibm.wsspi.jsp.disableResourceInjection false


com.ibm.wsspi.jsp.disableTldSearch

The com.ibm.wsspi.jsp.disableTldSearch custom property can be used to improve application startup time. By default, when an application starts, the JSP engine searches the application installation directories for the taglib descriptor (TLD) files. This search process might increase the startup time for large applications with many files and directories. To disable this search process, set this property to true.

Name Default
com.ibm.wsspi.jsp.disableTldSearch false


com.ibm.wsspi.jsp.enabledoublequotesdecoding

Set the com.ibm.wsspi.jsp.enabledoublequotesdecoding web container custom property to decode an encoded double quote character if it is embedded in a script function within a JSP file.

The JSP Container does not decode an encoded double quote character during the translation of a JSP file. Instead, there is a dependency on the browser to decode it. However, when an encoded double quote character exists inside a script function of a tag, the browser cannot decode it. Thus, when this custom property is not set, the encoded double quote character causes the script function to malfunction.

When you set this custom property, the value affects all of your deployed applications. To affect an individual application, set the enableDoubleQuotesDecoding JSP attribute to true within the ibm-web-ext.xmi file in the application.

Name Default
com.ibm.wsspi.jsp.enabledoublequotesdecoding false


com.ibm.wsspi.jsp.removexmlnsfromoutput

When the web container generates HTML code from a JSP document, the web container does not remove any xmlns attributes, specified for tags in the JSP document. Therefore, when the JSP document is rendered on the browser, the xmlns attributes remain in the generated HTML code.

To ensure the xmlns attributes are always removed from generated HTML code, add the com.ibm.wsspi.jsp.removexmlnsfromoutput custom property to the web container configuration settings and set this property to true.

When you set this custom property , the value affects all of your deployed applications. To affect an individual application, set the removeXmlnsFromOutput JSP attribute to true within the ibm-web-ext.xmi file in the application.

Name Default
com.ibm.wsspi.jsp.removexmlnsfromoutput false


DebugSessionCrossover

The DebugSessionCrossover custom property enables code to perform additional checks to verify that only the session associated with the request is accessed or referenced. Messages are logged if any discrepancies are detected.

The use of the DebugSessionCrossover property as a web container custom property is deprecated. We can now define it as a session management custom property.

To enable session data crossover detection, set this property to true

Name Default
DebugSessionCrossover false

Refer to the HTTP session problems article for additional information.


DecodeUrlAsUTF8

The UTF-8 encoded URL feature, which provides UTF-8 encoded Uniform Resource Locators (URLs) to support the double-byte characters in URLs is enabled by default. We can prevent the web container from explicitly decoding URLs in UTF-8 and have them use the ISO-8859 standard as per the current HTTP specification by setting this custom property to false.

Name Default
DecodeUrlAsUTF8 true


enableInProcessConnections

Use the enableInProcessConnections custom property to reduce response times and to reduce the number of threads used to service a request, which reduces the potential for a deadlock.

There is an optimized communication path between a web services client application and a web container located in the same application server process. Requests from the web services client that are normally sent to the web container using a network connection are delivered directly to the web container using an optimized local path. The local path is available because the web services client application and the web container are running in the same process. This optimized communication path is disabled by default. Before enabling this property, verify wild cards are not specified for the web container ports. Use specific ports for the web container when the optimized communication path is enabled.

To enable the optimized communication path, set this property to true.

Name Default
enableInProcessConnections false

Refer to the Web services client to web container optimized communication topic for additional information.


fileServingEnabled, directoryBrowsingEnabled, and serveServletsByClassnameEnabled

fileServingEnabled, directoryBrowsingEnabled, and similar properties are global settings for internal servlets. Web application archive (WAR) files that are packaged using third-party tools cannot specify behavior for the services that are exposed by the web container internal servlets.

We can use the fileServingEnabled, directoryBrowsingEnabled, and serveServletsByClassnameEnabled properties to globally enable and disable the fileServing, directoryBrowsing, and serveServletsByClassname functions for internal servlets for all web applications at the web container level.

Name Default
fileServingEnabled true
directoryBrowsingEnabled false
serveServletsByClassnameEnabled false

Settings that are defined in an assembly tool take precedence over the global settings that are set through the custom properties at the web container level.

Web application deployment extensions continue to hold configuration information for the services provided by the internal servlets, and take precedence over the global settings that are set through the custom properties at the web container level.


ForceSessionIdLengthCheck

Newly-generated session IDs are, by default, 23 characters in length, unless we use the HttpSessionIdLength custom property to specify a different maximum length for the session IDs.

When an incoming request has a session ID that is longer than the expected session ID length, and whose prefix is identical to a pre-existing session ID, the longer ID is used to return a new session. If the length of the session ID on the incoming request is larger then the maximum length specified for the system, such that it exceeds thewidth of the ID column in the session table column used in database persistence, an SQL0302 error occurs.

To prevent the occurrence of these SQL0302 errors, we can add the ForceSessionIdLengthCheck custom property to the web container custom properties and set it to true. When true, the length of a session ID cannot exceed 23 characters. If an incoming request has a session ID that is longer than 23 characters, the first 23 characters are used to return a new session.

Name Default
ForceSessionIdLengthCheck false


ForceSessionInvalidationMultiple

The ForceSessionInvalidationMultiple custom property indicates whether the session manager should wait indefinitely for a request to complete before attempting to invalidate the session, or attempt to invalidate a session after the specified time limit has elapsed.

Name Default
ForceSessionInvalidationMultiple 1

httpsIndicatorHeader

The custom property httpsIndicatorHeader manages HTTPS requests that are forwarded to an application server from an SSL offloader used in front of WAS. When an HTTPS request is received by an SSL offloader it is redirected over HTTP to an application server using WAS. The SSL offloader must be configured to add a special header indicating the original request was over HTTPS. The httpsIndicatorHeader property specifies the request header key name added by the SSL box. The application server checks this indicator to determine if SSL is required. If it determines the request is SSL over HTTP, an HTTPS scheme is chosen.

Name Default
httpsIndicatorHeader none


HttpSessionIdReuse

The custom property HttpSessionIdReuse determines whether the session manager can use the session ID sent from a browser to preserve session data across web applications that are running in an environment not configured for session persistence. In a multi-JVM environment, not configured for session persistence, setting this property to true enables the session manager to use the same session information for all of a user requests, even if the web applications that are handling these requests are governed by different JVM files. The default value for this property is false.

The use of the HttpSessionIdReuse property as a web container custom property is deprecated. You should now define this functionality as a session management custom property.

To enable the session manager to use the session ID sent from a browser to preserve session data across web applications that are running in an environment not configured for session persistence, set this property to true.

Name Default
HttpSessionIdReuse false


listeners

The servlet specification supports applications registering listeners for servlet-related events on an individual application basis through the web.xml descriptor. However, using the listeners custom property, we can enable a server to listen to servlet events across web applications.

To implement global listening, a listener is registered at the web container level and is propagated to all of the installed and new web applications. This global behavior of internal servlet listeners is controlled by the listeners custom property using the following name-value pair format.

Name Default
listeners none

The value for this property is a string, specifying a comma-separated list of listener classes. The listener supplied must implement standard listener classes from the Java Servlet API or IBM listener extension classes.


prependSlashToResource

WAS 5.x supports Uniform Resource Locators (URLs) without leading front slashes ( / ) . To preserve compatibility, we can set this custom property to true. When true, the web container ignores the specification and consider URLs without the leading front slash, use the following name-value pair.

Name Default
prependSlashToResource false


trusted

The trusted custom property enables the application server to use inbound private headers from the web server plug-in. These inbound private headers notify the application server about the connection to the web server. When you set the custom property to true, the application server uses the asserted information on the client certificates. These client certificates are used by the end user to connect to the web server and establish the client information, which is treated as the certificate for the end user. Then, the application server uses the certificate information for authentication purposes when client certificate authentication is used or when the application code accesses the javax.net.ssl.peer_certificates certificates. Because this information is asserted, it is insecure and potentially vulnerable to an attacker that is able to connect directly to the application server and bypass the web server.

If you allow direct connections to the application server and use client certificates, set this custom property to false.

Name Default
trusted true


UseOracleBLOB

The UseOracleBLOB custom property creates the HTTP session database table using the Binary Large Object (BLOB) data type for the medium column. This property increases performance of persistent sessions when Oracle databases are used.

Because of an Oracle restriction, BLOB support requires use of the oci database driver for Oracle for more than 4000 bytes of data. You must also ensure that a new sessions table is created before the server is restarted by dropping your old sessions table or by changing the datasource definition to reference a database that does not contain a sessions table.

To create a sessions table using the BLOB data type, set this property to true.

The use of the UseOracleBLOB property as a web container custom property is deprecated. You should now define this function as a session management custom property.

Name Default
UseOracleBLOB false


Related


Modify the default web container configuration
Configure transport chains


Reference:

HTTP transport custom properties
HTTP session problems
Web services client to web container optimized communication
JSP specific web container custom properties
HTTP transport channel custom properties


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