Developing Your First Portlet
Step 5 of 8
Recall that portlets run in a portion of a page, and a page can contain multiple portlets. Because of this, portlets have phases of operation. Here, you’ll learn about the most important two. The first phase is the one you’ve already used: the render phase. All this means is that the portlet draws itself, using the JSPs you write for it.
The other phase is called the action phase. This phase runs once, when a user triggers a portlet action. The portlet performs whatever action the user triggered, such as performing a search or adding a record to a database. Then, based on what happened in the action, the portlet goes back to the render phase and re-renders itself according to its new state.
To save a guestbook entry, you must trigger a portlet action. For this, you’ll create an action URL.
Add the following tag in edit_entry.jsp after the closing
</portlet:renderURL> tag:
<portlet:actionURL name="addEntry" var="addEntryURL"></portlet:actionURL>
You now have the two required URLs for your form.