JavaServer Faces

Using Value Binding Expressions

Let’s improve the filtering criteria form by binding the fields to properties of the ReportHandler class. Example 6-3 shows the new filtering criteria page with the value binding expressions added.

Example 6-3. New filtering criteria form with value binding expressions added (expense/stage2/filterArea.jsp)

<%@ page contentType="text/html" %>
<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %>

<f:view>
  <h:messages layout="table" />
  <h:form>
    From: <h:inputText size="8" value="#{reportHandler.from}" />
    <br>
    To: <h:inputText size="8" value="#{reportHandler.to}" />
    <br>
    Status:
    <h:selectManyCheckbox value="#{reportHandler.status}">
      <f:selectItem itemValue="1" itemLabel="Open" />
      <f:selectItem itemValue="2" itemLabel="Submitted" />
      <f:selectItem itemValue="3" itemLabel="Accepted" />
      <f:selectItem itemValue="4" itemLabel="Rejected" />
    </h:selectManyCheckbox>
    <p>
    <h:commandButton value="Filter" />
  </h:form>
</f:view>

The value attributes for the input components contain value binding expressions that point to the corresponding properties in a ReportHandler instance available through a variable named reportHandler. If you run this page, you’ll see that the default dates returned by the getFrom() and getTo( ) methods shown in Example 6-2 end up in the input fields, and the same goes for the default choices returned by the getStatus() method.