ADF Basics: Apply and Change WHERE Clause of ViewObject at runtime programmatically

This post is about applying or changing WHERE clause of ViewObject programmatically, it can be also used in case we need a specific data(row) from database, suppose you are using Department table of HR Schema and on a button click you need to show records of department id 5

It means you want to filter viewObject on that particular event, you can do this using setWhereClause mehtod of ViewObjectImpl class.
See the image below , all rows shown in this

Now when we click the button, it will filter (apply WHERE Clause in Departments ViewObject) rows and refresh ViewObject , returns desired rows.




For Department_Id 4-

For Department_Id 5-

To apply WHERE Clause , see this simple snippet of code

ViewObject v1 = am.getDepartment1();

v1.setWhereClause("DEPARTMENT_ID=4"); // Pass Where Clause String as Method Parameter

v1.executeQuery();

This code snippet fetch the Row with Deprartment_id=4 and returns back to page. setWhereClause sets the Query's (SQL) Where Clause and doesn't take effect until executeQuery method of ViewObjectImpl is called

To reset Where Clause we have to set null value in method used

ViewObject v1 = am.getDepartment1();

v1.setWhereClause(null); // To Remove Where Clause

v1.executeQuery();

Thanks , Happy Learning :)

Java Database Connectivity- JDBC Tutorial, PreparedStatement, ResultSet

JDBC is java based API or technology to access data from database and use in Java Desktop or Enterprize application. In short we can say JDBC is an interface between Java and Database, using JDBC you can interact with any of database as Oracle, MySQL, Access.
JDBC is released with JDK(Java Development Kit)1.1 on 19 Feb 1997 and It is a part of Java Standard Edition. if you know about DBMS(Database Management Systems) then you should know about Database Drivers, drivers are of 4 types.

1. Type 1 Driver - JDBC-ODBC bridge
2. Type 2 Driver - Native-API Driver
3. Type 3 Driver - Network-Protocol Driver(MiddleWare Driver)
4. Type 4 Driver - Native-Protocol Driver(Pure Java Driver)-Thin Driver

If you don't have java installed , follow the link below to donload it

JDK1.7- Download jdk1.7
Now we will learn that how to implement Database connection in Java. To start with JDBC you must have a little knowledge of DBMS and SQL(Structured Query Language) to interact with Database
here i will show you that how to connect with Oracle Database
Follow these steps to connect with Oracle Database

1. Load Driver (Thin Driver)

The very first step towards database connection is Loading Driver, as discussed we use pure java driver in JDBC connectivity there are two steps to load driver for connection

A. Using DriverManager class
The syntax is - DriverManager.registerDriver(DriverName);

1.         try {
2.             DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
3.            
4.         } catch (SQLException e) {
5.         }
6.        

B. Using Class.Forname class
The syntax is - Class.forName(”DriverName”);

1.         try {
2.              Class.forName("oracle.jdbc.driver.OracleDriver");
3.            
4.         } catch (SQLException e) {
5.         }
6.        

2. Create Connection

Connection interface is inside java.sql package and extends Wrapper interface. now to create Connection we register driver with DriverManager class.
Syntax is- DriverManager.getConnection("url string", "username", "password");

1. Connection con;
2.  try {
3.      DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
4.      con=DriverManager.getConnection(
5.      "jdbc:oracle:thin:@192.168.1.234:1521:XE", "hr", "hr");
6.  } catch (SQLException e) {
7.  }

You have to change url string with your ip address and SID according to your database setting

3. Execute PreparedStatement and return Resultset

Now we see that how to execute SQL query using PreparedStatement and store its result in ResultSet object
Here i am getting username and password from LOGIN_DET table (you can use your own query here)

1.         Connection con;
2.         try {
3.             DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
4.             con = DriverManager.getConnection("
5.            jdbc:oracle:thin:@192.168.1.241:1521:eadf", "hr", "hr");
6.             PreparedStatement psmt = con.prepareStatement("SELECT * FROM LOGIN_DET");
7.             ResultSet rs = psmt.executeQuery();
8.             if (rs.next()) {
9.                 while (rs.next()) {
10.                 System.out.println("Username is--" + rs.getString(1)
11.                + "and Password is-->" + rs.getString(2) +
12.                "Email Id is--->" + rs.getString("E_ID"));
13.                 }
14.             }
15.             psmt.close();
16.             con.close();
17.         } catch (SQLException e) {
18.         }

This is the brief overview of using JDBC with Oracle Database, For others you have to change only DriverName respectively
Happy Learning :)

ADF Basics: Disable user input in af:inputListOfValues

Sometimes we need to disable user input in input Lov as there is requirement of selecting value only from Lov popup

By default af:inputListOfValues provides feature to select value from popup or type a value as input

To disable user input there is a property -EditMode
From Oracle Docs-

editMode

String

Yes

Valid Values: input, select the mode that controls how the user specifies a value. This attribute is only applicable when the 'readOnly' attribute is set to false. input: this mode allows the user to type in a value as well as browse and select from a list of available values. select: this mode allows the user only to browse and select from a list of available values.

Set it's value to select

Happy Learning , Thanks :)