JSP programming (II)-JSP basic syntax (8)-JSP: getproperty

Obtains the bean property value, which is displayed on the page.

JSP syntax

<JSP: getproperty name ="Beaninstancename"Property ="Propertyname"/>

 

Example

<JSP: usebean id = "calendar" Scope = "page" class = "employee. Calendar"/>

<H2>

Calendar<JSP: getproperty name = "calendar" property = "username"/>

</H2>

 

Description

The <JSP: getproperty> element obtains the bean property value and can be used or displayed on the JSP page. before using <JSP: getproperty>, you must use <JSP: usebean> to create it.

<JSP: getproperty> elements have some restrictions:

• You cannot use <JSP: getproperty> to retrieve an indexed property.

• You can use <JSP: getproperty> with the JavaBeans component, but not with the EnterpriseBean.

   

Attribute

• Name ="Beaninstancename"

  Bean name, specified by <JSP: usebean>

   

• Property ="Propertyname"

  Attribute name of the specified bean.

 

TIPS:

• As mentioned in Sun's JSP reference, if you use <JSP: getproperty> to retrieve a null valueNullpointerexception will occur.ProgramSegment or expression to retrieve its value, then null (null) appears in the browser ).