Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Administration Reference

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web-container

Configures the web container.

Superelements

config

Subelements

The following table describes subelements for the web-container element.

Table 1–160 web-container Subelements


Element	Required	Description
session-config	zero or one	Specifies session configuration information for the web container.
property	zero or more	Specifies a property or a variable.

web-container-availability

Enables availability in the web container, including HTTP session persistence to the high-availability database (HADB).

If availability is disabled, there is no high availability for HTTP session persistence. In other words, persistence-type=memory.

If availability is enabled but no other web-container-availability attributes are specified, the default session persistence configuration is as follows:

persistence-type=ha
persistence-frequency=time-based
persistence-scope=session

The default configuration for all applications can be changed by setting the various web-container-availability attributes and properties.

You can override the various web-container-availability attributes and properties for a specific application in sun-web.xml. For details, see the Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Developer’s Guide.

Superelements

availability-service

Subelements

The following table describes subelements for the web-container-availability element.

Table 1–161 web-container-availability Subelements


Element	Required	Description
property	zero or more	Specifies a property or a variable.

Attributes

The following table describes attributes for the web-container-availability element.

Table 1–162 web-container-availability Attributes


Attribute	Default	Description
`availability-enabled`	`true`	(optional) If set to `true`, and if availability is enabled for the server instance (see availability-service), high-availability features apply to all web applications deployed to the server instance that do not have availability disabled. All instances in a cluster should have the same availability value to ensure consistent behavior.
`persistence-type`	`memory`	(optional) Specifies the session persistence mechanism for web applications that have availability enabled. Allowed values are `memory` (no persistence) `file` (the file system) and `ha` (the HADB). For production environments that require session persistence, use `ha`. If set to `memory`, the manager-properties element’s `sessionFilename` property specifies the file system location where the HTTP session state is stored if the server instance is gracefully shut down. This is useful for internal testing but is not supported for production environments. If set to `file`, the store-properties element’s `directory` property specifies the file system location where the HTTP session state is stored. Persisting to the file system is useful for internal testing but is not supported for production environments.
`persistence-frequency`	`web-method`	(optional) Specifies how often the session state is stored. Applicable only if the `persistence-type` is `ha`. Allowed values are as follows: `web-method` - The session state is stored at the end of each web request prior to sending a response back to the client. This mode provides the best guarantee that the session state is fully updated in case of failure. `time-based` - The session state is stored in the background at the frequency set by the `reapIntervalSeconds` property. This mode provides less of a guarantee that the session state is fully updated. However, it can provide a significant performance improvement because the state is not stored after each request.
`persistence-scope`	`session`	(optional) Specifies how much of the session state is stored. Applicable only if the `persistence-type` is `ha`. Allowed values are as follows: `session` - The entire session state is stored every time. This mode provides the best guarantee that your session data is correctly stored for any distributable web application. `modified-session` - The entire session state is stored if it has been modified. A session is considered to have been modified if `HttpSession.setAttribute()` or `HttpSession.removeAttribute()` was called. You must guarantee that `setAttribute()` is called every time an attribute is changed. This is not a J2EE specification requirement, but it is required for this mode to work properly. `modified-attribute` - Only modified session attributes are stored. For this mode to work properly, you must follow some guidelines, which are explained immediately following this table.
`sso-failover-enabled`	`false`	(optional) If `true`, the single sign-on state is highly available. To enable single sign-on, use the `sso-enabled` property of the virtual-server element.
`http-session-store-pool-name`	availability-service `store-pool-name` attribute value	(optional) Specifies the `jndi-name` of the jdbc-resource used for connections to the HADB for session persistence. For more information about setting up a connection pool and JDBC resource for the HADB, see the description of the `configure-ha-cluster` command in the Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Reference Manual.

If the persistence-scope attribute is set to modified-attribute , your web application must follow these guidelines:

Call setAttribute() every time the session state is modified.
Make sure there are no cross-references between attributes. The object graph under each distinct attribute key is serialized and stored separately. If there are any object cross references between the objects under each separate key, they are not serialized and deserialized correctly.
Distribute the session state across multiple attributes, or at least between a read-only attribute and a modifiable attribute.

web-module

Specifies a deployed web module.

Superelements

applications

Subelements

The following table describes subelements for the web-module element.

Table 1–163 web-module Subelements


Element	Required	Description
description	zero or one	Contains a text description of this element.

Attributes

The following table describes attributes for the web-module element.

Table 1–164 web-module Attributes


Attribute	Default	Description
`name`	none	The name of the web module.
`context-root`	none	The context root at which the web module is deployed. The context root can be the empty string or just `/`. The context root can start with the `/` character, but doesn’t have to. For load balancing to work, web module context roots must be unique within a cluster. See the Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Administration Guide for more information about load balancing.
`location`	none	A fully qualified or relative path to the directory to which the contents of the `.war` file have been extracted. If relative, it is relative to the following directory: `domain-dir/applications/j2ee-modules/`
`object-type`	`user`	(optional) Defines the type of the resource. Allowed values are: `system-all` - A system resource for all server instances and the domain application server. `system-admin` - A system resource only for the domain application server. `system-instance` - A system resource for all server instances only. `user` - A user resource.
`enabled`	`true`	(optional) Determines whether the web module is enabled.
`availability-enabled`	`false`	(optional) Specifies whether availability is enabled in this web application for HTTP session persistence (and potentially passivation). Availability must also be enabled for the application or stand-alone web module during deployment. For more information about availability, see availability-service.
`directory-deployed`	`false`	(optional) Specifies whether the application has been deployed to a directory.

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