Common Attributes

Although each Nuts tag has its own set of attributes, there are a few attributes that are common to either several or most of the tags:

Fundamentals

• singleton.
  • Applied to any Component tag.
  • It indicates whether we want singleton pattern applied to this Component.
  • Allowed values are: true, false, thread.
  • Default value: The global default value is used for global components; "false" for local and sub components.
  • Custom autowire mode can be registered.
• type.
  • Applied to any Component tag.
  • It explicitly declare the type of the component.
  • Also applied to literal tags such as <value>, <arg>, <prop>.
  • It converts the string literal to the target type.
  • Optional attribute.
• id.
  • Applied to any tag declared in the global scope or inside <local>, <sequence>, <binder> tags.
  • Allowed values: any valid id. No duplicate id allowed in the same scope.
  • Mandatory attribute wherever applicable.
• var.
  • Applied to the <binder> tag to indicate a bound variable.
  • Applied to sub-tags inside <sequence> and <binder> to declare local variables.
  • Allowed values: any valid id. No duplicate var allowed in the same scope.
  • var and id cannot duplicate either.
  • Mandatory attribute for <binder>.
• component.
  • Applied to many tags that accepts another Component. <bean>, <method>, <getter>, <setter>, <bind> all support this attribute.
  • Allowed values: any visible id or var.

Life Cycle attributes

• initializer.
  • Lifecycle specifier. Indicates which method to call to initialize it.
  • Allowed value: any valid method name.
  • Default value: n/a.
• disposer.
  • Lifecycle specifier. Indicates which method to call to dispose of it.
  • Allowed value: any valid method name.
  • Default value: n/a.
• starter.
  • Lifecycle specifier. Indicates which method to call to start it.
  • Allowed value: any valid method name.
  • Default value: n/a.
• stopper.
  • Lifecycle specifier. Indicates which method to call to stopper it.
  • Allowed value: any valid method name.
  • Default value: n/a.

These life cycle attributes are supported by <ctor>, <method>, <bean> tags.

Miscillaneous

• autowire.
  • Applied to any Component tag.
  • It indicates whether the component use auto-wiring to resolve dependency.
  • allowed values are: none, bytype, byname, byQualifiedName, autodetect.
  • Default value: none.
  • Custom autowire modes can be resitered. See Custom Autowire Mode - EJB3 style for details.
• eager-init.
  • Applied to any component declared at the global scope.
  • It indicates whether the component is eagerly instantiated.
  • allowed values are: true, false, yes, no, on, off.
  • Default value: specified by the global "eager-init" setting. "false" is global setting is not specified.
• private-access.
  • Applicable to <ctor>, <method>, <field>.
  • It indicates whether we allow access to non-public members.
  • Allowed values: true, false.
  • Default value: false.
• synchronized.
  • Applicable to every tag that evaluates to a Component.
  • It indicates whether the component instantiation is in a "synchronized" block to ensure thread safety. Operations done by Nuts and Yan (such as singleton) are always thread-safe regardless of this attribute. "synchronized" attribute can be used to protect method calls and java bean setters or their combinations that could be used in a multi-threaded environment.
  • Allowed values: true, false.
  • Default value: false.
• servlet-context-property
  • Applicable to <ctor>, <method> and <bean> in web integration.
  • Default value: "servletContext". So if the component has a method "setServletContext" with one ServletContext parameter, it will be called to set the ServletContext.
  • Setting "servlet-context-property" to "$null" or "" suppresses it.

Created by benyu benyu
On Mon Nov 14 23:31:13 CST 2005
Using TimTam