Java EE 8 Application Development
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Form submission

<h:commandButton> renders an HTML submit button in the browser. Just like with standard HTML, its purpose is to submit the form. Its value attribute simply sets the button's label. This tag's action attribute is used for navigation; the next page to show is based on the value of this attribute. The action attribute can have a String constant or a method binding expression, meaning that it can point to a method in a named bean that returns a string.

If the base name of a page in our application matches the value of the action attribute of a <h:commandButton> tag, then we navigate to this page when clicking the button. This JSF feature frees us from having to define navigation rules, like we used to have to do in older versions of JSF. In our example, our confirmation page is called confirmation.xhtml; therefore by convention, this page will be shown when the button is clicked, since the value of its action attribute (confirmation) matches the base name of the page.

Even though the label for the button reads Save, in our simple example, clicking on the button won't actually save any data.