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 :)

Searching pivotTable using dvt:pivotFilterBar in Oracle ADF

dvt:pivotTable-

From Oracle docs- The Pivot Table supports the display of multiple nested attributes on a row and column header. In addition, the Pivot Table supports the ability to dynamically change the layout of the attributes displayed in the row or column headers via drag and drop pivoting.

Framework provides  <dvt:pivotFilterBar>component to perform search operation on pivotTable
The PivotFilterBar component is used to filter data based on the selected criterion belonging to the PivotableQueryDescriptor as specified by the value property



In this example i am using Departments and Employees table of HR Schema, Created a query based viewObject using this query (to show Departments and it's Employees)

SELECT A.DEPARTMENT_ID,  
B.EMPLOYEE_ID, 
A.DEPARTMENT_NAME , 
B.FIRST_NAME||' '||B.LAST_NAME AS NAME,  
B.EMAIL,  
B.PHONE_NUMBER, 
B.HIRE_DATE, 
B.JOB_ID, 
B.SALARY, 
B.COMMISSION_PCT 
FROM DEPARTMENTS A, EMPLOYEES B 
WHERE A.DEPARTMENT_ID=B.DEPARTMENT_ID

Add this viewObject to Application Module and drop on page as pivot table from Data Control

Configuration for pivotTable-

Finally it looks like this-

Now i have dropped <dvt:pivotTable> on page and it automatically sets it's properties that are required for filtering pivotTable

<dvt:pivotFilterBar id="pt1pivotFilterBar" value="#{bindings.DeptEmp1.pivotFilterBarModel}"
                                    modelName="pt1Model"/>

Once check that modelName property should be same for both pivotTable and filterbar
Now run this application and drop any column on filterbar that you want to search

Sample ADF Application-Download
Cheers :) Happy Learning

Disable(Override) browser back button functionality in ADF Application using JavaScript

This is another JavaScript trick to disable browser back button functionality
In this example i am using two jspx pages - Page1 and Page2

Added two buttons in both pages to navigate between pages



Source of Page1-

<af:outputText value="Page 1" id="ot1" inlineStyle="font-size:medium;font-weight:bold;"/>
                <af:commandButton text="Go To Second Page" id="cb1" action="forward"/>

Source of Page2-

 <af:outputText value="Page 2" id="ot1" inlineStyle="font-size:medium;font-weight:bold;"/>
                <af:commandButton text="Go To First Page" id="cb1" action="backward"/>

Now see JavaScript function to disable back button functionality, In actual JavaScript doesn't disable back button but override it's default functionality
This function forces browser to navigate forward instead of going back so on click of back button first browser executes it's default back operation but due to this function again navigates to forward and show same page

function preventBackButton() {
                  window.history.forward();
              }

Add this javascript to Page 1 and invoke using af:clientListener tag on pageLoad

<af:clientListener method="preventBackButton" type="load"/>

Now run application and check
Go to second page and the press back button - it returns to page one for a fraction of second but again navigates to Page 2
It means it is working , Cheers :) Happy Learning

Working with af:iterator and af:forEach programmatically (Add and delete records using List)

In previous post Working with af:iterator and af:forEach programmatically (Populate values using POJO from Managed Bean) we saw that how can we populate record from a List to af:iterator and af:forEach (ADF Faces Component)

So this post is about adding and deleting of records from List while List is presented using af:iterator.
here i am extending previous post and using same sample application



Added two fields and button on page to add records 

<af:panelFormLayout id="pfl1" rows="1">
                    <af:inputText label="Name" id="it1" binding="#{viewScope.PopulateIteratorBean.nameBind}"/>
                    <af:inputText label="Department" id="it2" binding="#{viewScope.PopulateIteratorBean.deptNameBind}"/>
                    <af:button text="Add" id="b1"
                               actionListener="#{viewScope.PopulateIteratorBean.addNewRecordAction}"/>
                </af:panelFormLayout>

and on this button action simply added both attributes to List and added partial trigger of button to af:iterator to refresh it

    // Component binding to access inputValue from page
    
    private RichInputText nameBind;
    private RichInputText deptNameBind;
    
    public void setNameBind(RichInputText nameBind) {
        this.nameBind = nameBind;
    }

    public RichInputText getNameBind() {
        return nameBind;
    }

    public void setDeptNameBind(RichInputText deptNameBind) {
        this.deptNameBind = deptNameBind;
    }

    public RichInputText getDeptNameBind() {
        return deptNameBind;
    }

    /**Method to add record in List and show on page using af:iterator and af:forEach
     * @param actionEvent
     */
    public void addNewRecordAction(ActionEvent actionEvent) {
        if (nameBind.getValue() != null && deptNameBind.getValue() != null) {
            EmployeeDet obj = new EmployeeDet(nameBind.getValue().toString(), deptNameBind.getValue().toString());
            employeeDetail.add(obj);
            
        }
    }

On page - add a new record (record added in List and appeared in iterator as well)

So it is quite simple to add records but deletion of record is a bit tricky but not difficult at all :)
Let's see this-
For deleting record i have added a delete link inside iterator so that it should appear for each record as you can see in snap (above)
Here question is that how to know that which record should be deleted  ?

So for this i have added a f:attribute tag to link , this attribute contains the value of current item of iterator

f:attribute derives it's value from var of af:iterator/af:forEach, this var represents each item of List
Now on delete button's action - get the current item and remove it from List

    /**Method to delete selected record
     * @param actionEvent
     */
    public void deleteRecordAction(ActionEvent actionEvent) {
        //Get value from f:attribute (current item)
       Object itemVal= actionEvent.getComponent().getAttributes().get("itemVal");
       //Remove selected item from List
       employeeDetail.remove(itemVal);
    }

After deleting records

Sample ADF Application- Download