Appendix B: Example JDBC Programs
B.1 Using SELECT
import java.net.URL;
import java.sql.*;
class Select {
public static void main(String argv[]) {
try {
// Create a URL specifying an ODBC data source name.
String url = "jdbc:odbc:wombat";
// Connect to the database at that URL.
Connection con = DriverManager.getConnection(url, "kgh", "");
// Execute a SELECT statement
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery("SELECT a, b, c, d, key FROM Table1");
// Step through the result rows.
System.out.println("Got results:");
while (rs.next()) {
// get the values from the current row:
int a = rs.getInt(1);
BigDecimal b = rs.getBigDecimal(2);
char c[] = rs.getString(3).tocharArray();
boolean d = rs.getBoolean(4);
String key = rs.getString(5);
// Now print out the results:
System.out.print(" key=" + key);
System.out.print(" a=" + a);
System.out.print(" b=" + b);
System.out.print(" c=");
for (int i = 0; i < c.length; i++) {
System.out.print(c[i]);
}
System.out.print(" d=" + d);
System.out.print("\n");
}
stmt.close();
con.close();
} catch (java.lang.Exception ex) {
ex.printStackTrace();
}
}
}
B.2 Using UPDATE
// Update a couple of rows in a database.
import java.net.URL;
import java.sql.*;
class Update {
public static void main(String argv[]) {
try {
// Create a URL specifying an ODBC data source name.
String url = "jdbc:odbc:wombat";
// Connect to the database at that URL.
Connection con = DriverManager.getConnection(url, "kgh", "");
// Create a prepared statement to update the "a" field of a
// row in the "Table1" table.
// The prepared statement takes two parameters.
PreparedStatement stmt = con.prepareStatement(
"UPDATE Table1 SET a = ? WHERE key = ?");
// First use the prepared statement to update
// the "count" row to 34.
stmt.setInt(1, 34);
stmt.setString(2, "count");
stmt.executeUpdate();
System.out.println("Updated \"count\" row OK.");
// Now use the same prepared statement to update the
// "mirror" field.
// We rebind parameter 2, but reuse the other parameter.
stmt.setString(2, "mirror");
stmt.executeUpdate();
System.out.println("Updated \"mirror\" row OK.");
stmt.close();
con.close();
} catch (java.lang.Exception ex) {
ex.printStackTrace();
}
}
}
Monday, December 20, 2010
Below is a java swing code for the traditional Hello World program.
Basically, the idea behind this Hello World program is to learn how to create a java program, compile and run it. To create your java source code you can use any editor( Text pad/Edit plus are my favorites) or you can use an IDE like Eclipse.
import javax.swing.JFrame;
import javax.swing.JLabel;
//import statements
//Check if window closes automatically. Otherwise add suitable code
public class HelloWorldFrame extends JFrame {
public static void main(String args[]) {
new HelloWorldFrame();
}
HelloWorldFrame() {
JLabel jlbHelloWorld = new JLabel("Hello World");
add(jlbHelloWorld);
this.setSize(100, 100);
// pack();
setVisible(true);
}
}
Output
Basically, the idea behind this Hello World program is to learn how to create a java program, compile and run it. To create your java source code you can use any editor( Text pad/Edit plus are my favorites) or you can use an IDE like Eclipse.
import javax.swing.JFrame;
import javax.swing.JLabel;
//import statements
//Check if window closes automatically. Otherwise add suitable code
public class HelloWorldFrame extends JFrame {
public static void main(String args[]) {
new HelloWorldFrame();
}
HelloWorldFrame() {
JLabel jlbHelloWorld = new JLabel("Hello World");
add(jlbHelloWorld);
this.setSize(100, 100);
// pack();
setVisible(true);
}
}
Output
Java Swing class hierarchy
The class JComponent, descended directly from Container, is the root class for most of Swing’s user interface components.
Swing contains components that you’ll use to build a GUI. I am listing you some of the commonly used Swing components. To learn and understand these swing programs, AWT Programming knowledge is not required.
The class JComponent, descended directly from Container, is the root class for most of Swing’s user interface components.
Swing contains components that you’ll use to build a GUI. I am listing you some of the commonly used Swing components. To learn and understand these swing programs, AWT Programming knowledge is not required.
What is Swings in java ?
A part of The JFC
Swing Java consists of
Look and feel
Accessibility
Java 2D
Drag and Drop, etc
Compiling & running programs
‘javac’ && ‘java ’
Or JCreator / IDE
if you do not explicitly add a GUI component to a container, the GUI component will not be displayed when the container appears on the screen.
Swing, which is an extension library to the AWT, includes new and improved components that enhance the look and functionality of GUIs. Swing can be used to build Standalone swing gui Apps as well as Servlets and Applets. It employs a model/view design architecture. Swing is more portable and more flexible than AWT.
Swing Model/view design: The “view part” of the MV design is implemented with a component object and the UI object. The “model part” of the MV design is implemented by a model object and a change listener object.
Swing is built on top of AWT and is entirely written in Java, using AWT’s lightweight component support. In particular, unlike AWT, t he architecture of Swing components makes it easy to customize both their appearance and behavior. Components from AWT and Swing can be mixed, allowing you to add Swing support to existing AWT-based programs. For example, swing components such as JSlider, JButton and JCheckbox could be used in the same program with standard AWT labels, textfields and scrollbars. You could subclass the existing Swing UI, model, or change listener classes without having to reinvent the entire implementation. Swing also has the ability to replace these objects on-the-fly.
100% Java implementation of components
Pluggable Look & Feel
Lightweight components
Uses MVC Architecture
Model represents the data
View as a visual representation of the data
Controller takes input and translates it to changes in data
Three parts
Component set (subclasses of JComponent)
Support classes
Interfaces
In Swing, classes that represent GUI components have names beginning with the letter J. Some examples are JButton, JLabel, and JSlider. Altogether there are more than 250 new classes and 75 interfaces in Swing — twice as many as in AWT.
A part of The JFC
Swing Java consists of
Look and feel
Accessibility
Java 2D
Drag and Drop, etc
Compiling & running programs
‘javac
Or JCreator / IDE
if you do not explicitly add a GUI component to a container, the GUI component will not be displayed when the container appears on the screen.
Swing, which is an extension library to the AWT, includes new and improved components that enhance the look and functionality of GUIs. Swing can be used to build Standalone swing gui Apps as well as Servlets and Applets. It employs a model/view design architecture. Swing is more portable and more flexible than AWT.
Swing Model/view design: The “view part” of the MV design is implemented with a component object and the UI object. The “model part” of the MV design is implemented by a model object and a change listener object.
Swing is built on top of AWT and is entirely written in Java, using AWT’s lightweight component support. In particular, unlike AWT, t he architecture of Swing components makes it easy to customize both their appearance and behavior. Components from AWT and Swing can be mixed, allowing you to add Swing support to existing AWT-based programs. For example, swing components such as JSlider, JButton and JCheckbox could be used in the same program with standard AWT labels, textfields and scrollbars. You could subclass the existing Swing UI, model, or change listener classes without having to reinvent the entire implementation. Swing also has the ability to replace these objects on-the-fly.
100% Java implementation of components
Pluggable Look & Feel
Lightweight components
Uses MVC Architecture
Model represents the data
View as a visual representation of the data
Controller takes input and translates it to changes in data
Three parts
Component set (subclasses of JComponent)
Support classes
Interfaces
In Swing, classes that represent GUI components have names beginning with the letter J. Some examples are JButton, JLabel, and JSlider. Altogether there are more than 250 new classes and 75 interfaces in Swing — twice as many as in AWT.
Wednesday, September 22, 2010
import java.io.*;
import java.util.*;
public class calculator
{
public static void main(String[] args) throws IOException
{
BufferedReader keyboard = new BufferedReader (new InputStreamReader (System.in));
String input, input1, input2;
int num1, num2, answer;
System.out.println ("\t\t\tWelcome to the calculator!");
do
{
System.out.print ("\nWould you like to Multiply(m), Divide(d), Subtract(s), Add(a)?: ");
input = keyboard.readLine();
if (input.equals("m"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1*num2;
System.out.print ("You chose to multiply."+"\t"+"The Product is: "+answer);
}
if (input.equals("d"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1/num2;
System.out.print ("You chose to divide."+"\t"+"The Dividend is: "+answer);
}
if (input.equals("a"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1+num2;
System.out.print ("You chose to add."+"\t"+"The Sum is: "+answer);
}
if (input.equals("s"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1-num2;
System.out.print ("You chose to subtract."+"\t"+"The Diffrence is: "+answer);
}
System.out.print ("\nWould you like another calculation (y/n)?: ");
input = keyboard.readLine();
}
while(input.equals("y"));
if(input.equals("n"));
System.exit(0);
}
}
import java.util.*;
public class calculator
{
public static void main(String[] args) throws IOException
{
BufferedReader keyboard = new BufferedReader (new InputStreamReader (System.in));
String input, input1, input2;
int num1, num2, answer;
System.out.println ("\t\t\tWelcome to the calculator!");
do
{
System.out.print ("\nWould you like to Multiply(m), Divide(d), Subtract(s), Add(a)?: ");
input = keyboard.readLine();
if (input.equals("m"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1*num2;
System.out.print ("You chose to multiply."+"\t"+"The Product is: "+answer);
}
if (input.equals("d"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1/num2;
System.out.print ("You chose to divide."+"\t"+"The Dividend is: "+answer);
}
if (input.equals("a"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1+num2;
System.out.print ("You chose to add."+"\t"+"The Sum is: "+answer);
}
if (input.equals("s"))
{
System.out.print ("Please enter the first number!: ");
num1 = Integer.parseInt (input1 = keyboard.readLine());
System.out.print ("Please enter the second number!: ");
num2 = Integer.parseInt (input2 = keyboard.readLine());
answer = num1-num2;
System.out.print ("You chose to subtract."+"\t"+"The Diffrence is: "+answer);
}
System.out.print ("\nWould you like another calculation (y/n)?: ");
input = keyboard.readLine();
}
while(input.equals("y"));
if(input.equals("n"));
System.exit(0);
}
}
import java.io.*;
class twodimensional
{
public static void main(String args[])
{
float b[][]=new float [4][5];
int i,j;
float k=0;
for(i=0;i<4;i++)
for(j=0;j<5;j++)
{
b[i][j]=k;
k++;
}
for(i=0;i<4;i++)
{
for(j=0;j<5;j++)
System.out.println(b[i][j]+"");
System.out.println();
}
}
}
package com.gpt;
import javax.swing.JOptionPane;
/*
This program computes Fibonacci numbers using a recursive
method.
*/
public class Fibonacci
{
public static void main(String[] args)
{
String input = JOptionPane.showInputDialog("Enter n: ");
int n = Integer.parseInt(input);
for (int i = 1; i <= n; i++)
{
int f = fib(i);
System.out.println("fib(" + i + ") = " + f);
}
System.exit(0);
}
/**
Computes a Fibonacci number.
@param n an integer
@return the nth Fibonacci number
*/
public static int fib(int n)
{
if (n <= 2)
return 1;
else
return fib(n - 1) + fib(n - 2);
}
}
abstract class figure
{
double d1,d2;
figure(double x,double y)
{
d1=x;
d2=y;
}
public abstract double area ();
}
class rectangle extends figure
{
rectangle(double a,double b)
{
super (a,b);
}
public double area ()
{
System.out.println("area of the rectangle is");
return d1*d2;
}
}
class triangle extends figure
{
triangle (double p,double q)
{
super(p,q);
}
public double area()
{
System.out.println("area of the triangle");
return(d1*d2)/2;
}
public static void main(String args[])
{
//figure f= new figure();
rectangle r= new rectangle(10,20);
triangle t= new triangle (15,20);
figure ff;
ff=r;
ff.area();
ff=t;
}
}
import java.io.*;
class student
{
int rollno;
string name;
long marks;
char grades;
void fill details()
{
roll no=121;
name='uzair';
marks=270;
grades='A';
}
void showdetails()
{
system.out.println("roll no:"=roll name);
system.out.println("name:"+name);
system.out.println("marks:"+marks);
system.out.println("grades of the students is grades");
}
}
class studentdemo
{
public static void main(string a[])
{
system.out.println("this is main menu");
{
studnet st = new student();
st.filldetails();
st.showdetails();
}
}
Sunday, January 31, 2010
IF ANY TIME U GET THE VIRUS DONT BE PANIC JUST FOLLOW THIS STEPS AND HOPE U WILL BE GET RIDE OF IT ....IF NOT U CAN JUST COMMENT ME I WILL HELP U ....
REGARDS,
M.A.HAMEED.
