org.apache.struts2.components
类 Bean

java.lang.Object
  org.apache.struts2.components.Component
      org.apache.struts2.components.ContextBean
          org.apache.struts2.components.Bean

public class Bean
extends ContextBean

Instantiates a class that conforms to the JavaBeans specification. This tag has a body which can contain a number of Param elements to set any mutator methods on that class.

If the var attribute is set on the BeanTag, it will place the instantiated bean into the stack's Context.

• var - the stack's context name (if supplied) that the created bean will be store under
• name* - the class name of the bean to be instantiated (must respect JavaBean specification)

Examples:

 
 <-- in freemarker form -->
 [@s.bean name="org.apache.struts2.example.counter.SimpleCounter" var="counter"]
   [s:param name="foo" value="BAR"/]
   The value of foo is : [s:property value="foo"/], when inside the bean tag.

 [/s:bean]

 <-- in jsp form -->
 <s:bean name="org.apache.struts2.example.counter.SimpleCounter" var="counter">
   <s:param name="foo" value="BAR" />
   The value of foot is : <s:property value="foo"/>, when inside the bean tag <br />
 </s:bean>
 
 

This example instantiates a bean called SimpleCounter and sets the foo property (setFoo('BAR')). The SimpleCounter object is then pushed onto the Valuestack, which means that we can call its accessor methods (getFoo()) with the Property tag and get their values.

In the above example, the id has been set to a value of counter. This means that the SimpleCounter class will be placed into the stack's context. You can access the SimpleCounter class using a Struts tag:

 <-- jsp form -->
 <s:property value="#counter" />

 <-- freemarker form -->
 [s:property value="#counter.foo"/]
 

In the property tag example, the # tells Ognl to search the context for the SimpleCounter class which has an id(key) of counter

另请参见：

Param

字段摘要

从类 org.apache.struts2.components.Component 继承的字段

COMPONENT_STACK

构造方法摘要

Bean(com.opensymphony.xwork2.util.ValueStack stack)

方法摘要

void	addParameter(String key, Object value) Adds the given key and value to this component's own parameter.
boolean	end(Writer writer, String body) Callback for the end tag of this component.
void	setName(String name)
void	setObjectFactory(com.opensymphony.xwork2.ObjectFactory objectFactory)
void	setReflectionProvider(com.opensymphony.xwork2.util.reflection.ReflectionProvider prov)
boolean	start(Writer writer) Callback for the start tag of this component.

从类 org.apache.struts2.components.ContextBean 继承的方法

setId, setVar

从类 org.apache.struts2.components.Component 继承的方法

addAllParameters, altSyntax, copyParams, getComponentStack, getParameters, getStack, setActionMapper, setThrowExceptionsOnELFailure, setUrlHelper, usesBody

从类 java.lang.Object 继承的方法

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

构造方法详细信息

Bean

public Bean(com.opensymphony.xwork2.util.ValueStack stack)

方法详细信息

setObjectFactory

public void setObjectFactory(com.opensymphony.xwork2.ObjectFactory objectFactory)

setReflectionProvider

public void setReflectionProvider(com.opensymphony.xwork2.util.reflection.ReflectionProvider prov)

start

public boolean start(Writer writer)

从类 Component 复制的描述

Callback for the start tag of this component. Should the body be evaluated?

覆盖：

类 Component 中的 start

参数：

writer - the output writer.

返回：

true if the body should be evaluated

end

public boolean end(Writer writer,
                   String body)

从类 Component 复制的描述

Callback for the end tag of this component. Should the body be evaluated again?

NOTE: will pop component stack.

覆盖：

类 Component 中的 end

参数：

writer - the output writer.

body - the rendered body.

返回：

true if the body should be evaluated again

addParameter

public void addParameter(String key,
                         Object value)

从类 Component 复制的描述

Adds the given key and value to this component's own parameter.

If the provided key is null nothing happens. If the provided value is null any existing parameter with the given key name is removed.

覆盖：

类 Component 中的 addParameter

参数：

key - the key of the new parameter to add.

value - the value assoicated with the key.

setName

public void setName(String name)