Converter Instance
Converter Instance
Each of the component properties can be bound to one of the following:
A component's value
A component instance
A converter instance
A listener instance
A validator instance
The most common functions that backing bean methods perform include the following:
Validating a component's data
Handling an event fired by a component
Performing processing to determine the next page to which the application must navigate
As with all JavaBeans components, a property consists of a private data field and a set of
accessor methods, as shown by this code from the Guess Number example:
Integer userNumber = null;
...
public void setUserNumber(Integer user_number) {
userNumber = user_number;
}
public Integer getUserNumber() {
return userNumber;
}
public String getResponse() {
...
}
Because backing beans follow JavaBeans component conventions, you can reference beans
you've already written from your JavaServer Faces pages.
When a bean property is bound to a component's value, it can be any of the basic primitive and
numeric types or any Java object type for which the application has access to an appropriate
converter. For example, a property can be of type Date if the application has access to a
converter that can convert the Date type to a String and back again. See
for information on which types are accepted by which component tags.
When a bean property is bound to a component instance, the property's type must be the same
as the component object. For example, if a UISelectBoolean is bound to the property, the
property must accept and return a UISelectBoolean object.
Likewise, if the property is bound to a converter, validator, or listener instance then the
property must be of the appropriate converter, validator, or listener type.
For more information on writing beans and their properties, see
Backing Beans
The Java EE 5 Tutorial · September 2007
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