Java RowSet with examples on Driver, DriverManager, Connection, Statement, ResultSet, PreparedStatement, CallableStatement, ResultSetMetaData. This article introduces the JdbcRowSet interface and its basic usage. This class is defined in the package. JdbcRowSet. jdbc rowset, rowset java, jdbc resultset example, jdbc rowset vs resultset, JDBC RowSet Example. In this tutorial you will learn about wSet.
|Country:||Republic of Macedonia|
|Published (Last):||9 May 2004|
|PDF File Size:||16.96 Mb|
|ePub File Size:||15.32 Mb|
|Price:||Free* [*Free Regsitration Required]|
Fowset interfaces contain the methods that will be called by the client class. In order to get its data, a JdbcRowSet object first needs to connect to a database.
As an example, the following code fragment uses the Connection object con to create a Statement object, stmtwhich then executes a query. A ResultSet object that is not scrollable can use only the next method to move its cursor forward, and it can move the cursor only forward from the first row to the last row.
The other properties are all optional for the owner, so the programmer does not set any others. On the office machine, the rowset can create a connection for writing updated values back to the database. As the signature indicates, this method returns a RowSet object.
As the conceptual description of rowsets pointed out, what you can do with a rowset depends on how it has been implemented. As is true with other Beans, application programmers will probably use a development tool to create a RowSet object and set its properties.
This means that if the connection is valid, it will be returned to the connection pool to be reused. The order form rowset also needs no command property because the getCoffees implementation executes the query to get coffee names and prices.
The listener would therefore implement the RowSetListener methods to define what it will do when a particular event occurs. For all RowSet objects, three events trigger notifications:. Using Transactions Next page: This means that they have the following: If the owner knows that Espresso is in the third row of the jdbcRs object, the code for doing this might look like the following:. CoffeesBeansupplied by the developer, actually defines what the methods do.
The final part of our EJB component is the class CoffeesBeanwhich implements the methods that are declared in the interfaces Coffees and CoffeesHome and that are invoked in the class CoffeesClient. As a result of this call, the rowset does all of the following behind the scenes:. These implementations will have different names and constructors.
One of the main uses of a JdbcRowSet object is to make a ResultSet object scrollable and updatable when it does not otherwise have those capabilities. In this tutorial you will learn how to use these reference implementations.
JDBC RowSet Example
For example, not having to maintain a connection to a data source makes disconnected RowSet objects far more lightweight than a JdbcRowSet object or a ResultSet object. By using the reference implementation constructor that takes a ResultSet object By using the reference implementation constructor that takes a Connection object By using the reference implementation default constructor By using an instance of RowSetFactorywhich is created from the class Rowsset Note: The next part walks you through creating and using a rowset.
Being a JavaBeans component, a RowSet object has the ability to participate in event notification. For security, the programmer may opt to get the user name and password from the owner interactively at run time, in which case he would not need to set them as properties.
Using JdbcRowSet Objects
The home interface CoffeesHome is a factory for Coffees objects. All RowSet objects have properties. The main difference is that the rowset used in the order form for The Coffee Break is not updatable by the client; it is simply a jdvc of coffees and their prices that the manager can look at.
A RowSet object rowsett scrollable and updatable by default, so by populating a RowSet object with the contents of a result set, you can effectively make the result set scrollable and updatable.
This RowSet object paves the way for a disconnected yet live filtering mechanism without firing a query into the database every time. Notice that because the jdbcRs object is always connected to the database, inserting a row into a JdbcRowSet object is the same as inserting a row into a ResultSet object: Some of the products that appear on this site are from companies from which QuinStreet receives compensation. Because a RowSet object follows the JavaBeans model for properties and event notification, it is a JavaBeans component that can be combined with other components in an application.
In the application we are considering, the Projector Bean needs to be notified when the rowset is updated, so it needs to be registered with the rowset as a listener. The following information shows how they are related:. The third tier is one or more database servers.
If no one has changed values in the table, the rowset’s original values and the values in the database should be the same. The preceding code fragment goes through this process twice, so two new rows are inserted into the jdbcRs object and the database. However, this does not mean it lacks the capability of JdbcRowSet ; on the contrary, it is equipped with the additional capability of caching.
For example, the following lines of code move the cursor to the fourth row in the jdbcRs object and then back to the third row:. The following example uses several properties and explains why they are needed. The difference is that because the application developer has set the properties on the rowset to make it scrollable and updatable, the owner can move the cursor to any position in the rowset and modify its data.
Post a comment Email Article Print Article. Only one of the standard RowSet implementations is a connected RowSet object: When the method has completed, the container will commit the transaction. With a non-scrollable rowset or result set, you are limited to iterating through the data once and in a forward direction.
Disconnected RowSet objects are also serializable, and the combination of being both serializable and lightweight makes them ideal for sending data over a network.
This means we can now move back and forth the list of records fetched from the database through the ResultSet object, which otherwise would not have been easily possible.
Before writing new roaset to the database, the rowset’s writer component works behind the scenes to compare the rowset’s original values with those in the database. After reading data from or writing data to its data source, the RowSet object disconnects from it, thus becoming “disconnected.
A JdbcRowSet object can be used this way because it is effectively a wrapper for the driver that obtained its connection to the database.