It uses the primary key to find the matching entity instance, then invokes the get and set methods from the Users class to make the necessary changes to the table columns (Name, email address, and password), and commits the changes to end the transaction.After adding the code to the The Model App User Controller class, you are ready to change the Page1 web page in the The Web App project.Now we show you how to use the Visual Web features to create a web page and a Table component that more closely approximates that of a “real world” application.

updating and retrieving data from java servlet to sql database-69

This is the second part version 2 in a two-part series.

You should have completed the first part and have created the two projects described in that tutorial, along with the different classes and web page.

Then, we'll show you how to modify the page in My Test Web App.

We also explain the code you need to add to different Button component handlers so that everything works as intended.

Similar to the add User method, this method establishes a transaction context, uses the primary key to locate the database table row that matches the entity to be deleted, then removes that entity instance.

The commit call completes the removal and ends the transaction.

You also modify the My Test Web App page that displays the Table component, adding functionality that enables user interaction and improves the table display.

Let's start by modifying the code in My Test Model App.

The first tutorial provides all the information necessary to set up these two projects.

The first tutorial provided background on the Java Persistence API.

In this tutorial we will use the same Java Persistence API (JPA) and Visual Web (JSF) Table component to add, update, and delete database table rows.