Our Java: December 2010

Thursday, December 23, 2010

Program to insert new name and age information entered by the user into the database.

cust.html

   <html>

   <body>
   Enter the Customer details to add a record in Customer table
   <br>
   <form action="http://192.168.8.3/naveen/cust.php" method="get">
   Name:<input type="text" name="uname">
   Age:<input type="text" name="uage">
   <input type="submit" >
   <input type="reset">
   </form>


   </body>
   </html>

output:
-----------------------------------------------------------------------------------------------------------------------------------
Enter the Customer details to add a record in Customer table

$name=$_GET["uname"];

$age=$_GET["uage"];

$query1="Insert into customer values('$name',$age)";

echo "$query1";

// connect to the mysql server on localhost

$mysql = mysql_connect("192.168.8.3", "naveen", "a")

or die("could not connect to mysql");

// execute the MySQL query, grab the result in $result

$result1 = mysql_db_query("naveen", $query1)

or die("query failed ");

$query2="select * from customer";

echo "$query2";

$result = mysql_db_query("studentinfo", $query2)

or die("query failed ");

<html>

<head>

<title>PHP and MySQL</title>

</head>

We Added the Record:

<hr>

We found <b> <?echo mysql_num_rows($result); ?></b> rows.

<h3>Query result</h3>

<br>

<tr>

</tr>

//loop through each row

while ($array = mysql_fetch_row($result))

{

echo "<tr>";

echo "<td>$array[0]</td>";

echo "<td>$array[1]</td>";

echo "</tr>";

}

</table>

</body>

</html>

// we are all done, so close the MySQL connection

mysql_close($mysql);

-------------------------------------------------------------------------------------------------------------

OUTPUT:

Insert into customer values('naveen11',27)

We Added the Record:

We found rows.

Query result select * from customer

NAME	AGE
jhonny	22
bravo	22
naveen	27
xyz	27
abc	27

Program to display the current contents of the table in a database.

display.php

   <?
   // connect to the mysql server on localhost
   $mysql = mysql_connect("192.168.8.3", "naveen", "a")
   or die("could not connect to mysql");

   // execute the MySQL query, grab the result in $result
   $result = mysql_db_query("naveen", "SELECT * FROM student")
   or die("query failed ");

   ?>
   <html>
   <head>
   <title>PHP and MySQL</title>
   </head>
   <body bgcolor="CYAN">
   We executed: <b> SELECT * FROM student</b>
   <hr>
   We found <b><?echo mysql_num_rows($result); ?></b> rows.

   <h3>Query result</h3>
   <br>
   <table border=2>
   <tr>
<td>USN</td>
<td>NAME</td>
<td>BRANCH</td>
<td>SEM</td>
<td>CGPA</td>
   </tr>

   <?
   //loop through each row
   while ($array = mysql_fetch_row($result))
{
   echo "<tr>";

echo "<td>$array[0]</td>";
echo "<td>$array[1]</td>";
echo "<td>$array[2]</td>";
echo "<td>$array[3]</td>";
echo "<td>$array[4]</td>";
echo "</tr>";

}
   ?>
   </table>
   </body>
   </html>
   <?
   // we are all done, so close the MySQL connection
   mysql_close($mysql);
   ?>
OUT PUT:

We executed: SELECT * FROM student

We found 7 rows.

Query result

USN	NAME	BRANCH	SEM	CGPA
2sd02is006	jhon	cse	7	8.75
2sd02is007	jackie	ec	5	7.75
2sd02is008	tom	ee	5	6.75
2sd02is008	jerry	ise	7	7.77
2sd02is015	ford	ise	5	5.55
ytyutyu	ee	ee	2	5.55
2sd05is099	nnnnn	ise	7	9.99

Program to keep track of the number of visitors, visited the web page and display the counter with proper headings.

count.html
<html>
<body>
To know the no of times the web page Count.php is viewed <a href="http://192.168.8.3/naveen/count.php">Click Here</a>
</body>
</html>

count.php

<?

$filename = 'c.txt';

if (file_exists($filename))
   {
   $count = file('c.txt'); //read all the lines from the file c.txt and store it in array
   $count[0] ++;//increment the first line
   $fp = fopen("c.txt", "w"); //open c.txt in write mode
   fputs ($fp, "$count[0]"); //put the updated value in c.txt
   fclose ($fp);
   echo "No of vistors vistin the pages is $count[0]";
   }
?>
Note:For this code u hav to create c.txt in u r webcontainer
go to u r web contain
cd /var/www/html/<usn>
vi c.txt
enter the value 0 and save it
change the permission of c.txt to 777
access the html to see the no of times the page is visited.

Program to accept UNIX command from a HTML form and display the output of the command executed.

cmd.html
<html>
<body>
Enter the valid Linux command :
<form action="http://192.168.8.3/naveen/cmd.php" method ="get">
<input type="text" name="cmd">
<input type="submit">
</form>
</body>
</html>

cmd.php

<html>
<body>
<? $cmd=$_GET["cmd"];?>
The output of the command <? echo "$cmd"; ?> is:
<br>
<? $s=system($cmd);
echo "$s";
?>
</body>
</html>

Note : if we use exec($cmd) it will only print the last line of the output command so its better to use
system($cmd); which will print all the lines of the output of the command.

A Simple PHP

<html>
<body>
<?
echo "Welcome To My First PHP Page"<br>";

$name="naveen";
$sem=7;
$cgpa=7.77;
$cgpa2=$cgpa*10;
echo $name;
echo "<br>";
echo $sem;
echo "<br>";
echo $cgpa;
echo "<br>";
echo $cgpa2;

?>
</body>
</html>

Wednesday, December 22, 2010

JDBC ResultSet MetaData

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;

public class MyResultSetMetaData {
   public static void main(String[] args) throws Exception {
   Connection conn = getHSQLConnection();
   Statement st = conn.createStatement();


   st = conn.createStatement();
   ResultSet rs = st.executeQuery("SELECT * FROM student");

   ResultSetMetaData rsMetaData = rs.getMetaData();

   int numberOfColumns = rsMetaData.getColumnCount();
   System.out.println("resultSet MetaData column Count=" + numberOfColumns);

   String TableName = rsMetaData.getTableName(1);
   System.out.println("resultSet MetaData TableName=" + TableName);



   String ColumnLabel = rsMetaData.getColumnLabel(1);
   System.out.println("resultSet MetaData column Label 1=" + ColumnLabel);

   String ColumnLabe2 = rsMetaData.getColumnLabel(2);
   System.out.println("resultSet MetaData column Label 2=" + ColumnLabe2);


   rs.close();
   st.close();
   conn.close();
   }

   private static Connection getHSQLConnection() throws Exception {
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql://localhost/studentinfo";
   return DriverManager.getConnection(url, "root", "root");
   }
}
output

resultSet MetaData column Count=5
resultSet MetaData TableName=student
resultSet MetaData column Label 1=usn
resultSet MetaData column Label 2=name

JDBC Database MetaData

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;

public class Main {
   public static void main(String[] args) throws Exception {
   Connection conn = getConnection();

   DatabaseMetaData mtdt = conn.getMetaData();
   System.out.println("URL in use: " + mtdt.getURL());
   System.out.println("User name: " + mtdt.getUserName());
   System.out.println("DBMS name: " + mtdt.getDatabaseProductName());
   System.out.println("DBMS version: " + mtdt.getDatabaseProductVersion());
   System.out.println("Driver name: " + mtdt.getDriverName());
   System.out.println("Driver version: " + mtdt.getDriverVersion());
   System.out.println("supp. SQL Keywords: " + mtdt.getSQLKeywords());


   conn.close();
   }

   private static Connection getConnection() throws Exception {
   Class.forName("com.mysql.jdbc.Driver");
   String url = "jdbc:mysql://localhost/studentinfo";

   return DriverManager.getConnection(url, "root", "root");
   }
}
output

URL in use: jdbc:mysql://localhost/studentinfo
User name: root@localhost
DBMS name: MySQL
DBMS version: 5.0.27-community-nt
Driver name: MySQL-AB JDBC Driver
Driver version: mysql-connector-java-5.0.5 ( $Date: 2007-03-01 00:01:06 +0100 (Thu, 01 Mar 2007) $, $Revision: 6329 $ )

Using Prepared Statement

In this code we r makin use of the PreparedStatement for displayin a particular student record from student table

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/*
* Display.java
*
* Created on December 14, 2010, 9:25 AM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/

/**
*
* @author Naveen
*/
public class Display {

   /** Creates a new instance of Display */
   public Display() {
   }
   public static void main(String args[]) {
   PreparedStatement pstmt=null;
   Connection conn = null;
   ResultSet rs=null;

   try {
   Class.forName("com.mysql.jdbc.Driver");
   } catch (ClassNotFoundException ex) {
   ex.printStackTrace();
   }
   String url="jdbc:mysql://localhost/studentinfo";
   String userName="root";
   String password="root";
   try {

   conn=DriverManager.getConnection(url,userName,password);

   }

   catch (SQLException ex) {
   System.out.println("Unable to Connect to Database");
   }

   try {

   String query="select * from student where cgpa=? and sem =?";
   pstmt=conn.prepareStatement(query);

   pstmt.setFloat(1,8.75f);
   pstmt.setInt(2,7);
   rs =pstmt.executeQuery();
   while(rs.next()) {
   System.out.print(rs.getString(1)+"\t");
   System.out.print(rs.getString(2)+"\t");
   System.out.print(rs.getString(3)+"\t");

   System.out.print(rs.getInt(4)+"\t");
   System.out.print(rs.getFloat(5)+"\t");
   }


   } catch (SQLException ex) {
   System.out.println("Unable to create Statment");
   }





   }
}

Displaying all the records from Student table

Here in this code we r displaying all the student records from student table.In this example code we are makin use of jdbc driver type 4 provided by mysql.

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/*
* Display.java
*
* Created on December 14, 2010, 9:25 AM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/

/**
*
* @author Naveen
*/
public class Display2 {

   /** Creates a new instance of Display */
   public Display2() {
   }
   public static void main(String args[]) {

   Connection conn = null;
   ResultSet rs=null;
   Statement stmt = null;
   try {
   Class.forName("com.mysql.jdbc.Driver");
   } catch (ClassNotFoundException ex) {
   ex.printStackTrace();
   }
   String url="jdbc:mysql://localhost/studentinfo";
   String userName="root";
   String password="root";
   try {

   conn=DriverManager.getConnection(url,userName,password);

   }

   catch (SQLException ex) {
   System.out.println("Unable to Connect to Database");
   }

   try {

   String query="Select * from student" ;
   stmt=conn.createStatement();


   rs= stmt.executeQuery(query);
   while(rs.next()) {
   System.out.print(rs.getString("usn")+"\t");
   System.out.print(rs.getString(2)+"\t");
   System.out.print(rs.getString(3)+"\t");

   System.out.print(rs.getInt(4)+"\t");
   System.out.println(rs.getFloat(5)+"\t");
   }




   } catch (SQLException ex) {
   System.out.println("Unable to create Statment");
   }





   }
}

The JDBC Process

Here in this code we r inserting a student record into a student table.In this example code we are makin use of jdbc driver type 4 provided by mysql.

import java.io.DataInputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
/*
* DemoJdbc.java
*
* Created on December 13, 2010, 10:23 PM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/

/**
*
* @author Naveen
*/
public class DemoJdbc {

   /** Creates a new instance of DemoJdbc */
   public DemoJdbc() {

   }
   public static void main(String args[]) {
   DataInputStream din=new DataInputStream(System.in);
   Connection conn = null;
   Statement stmt = null;

   try {
   System.out.println("Enter the data usn,name,branch,sem,cgpa");
   String usn=din.readLine();
   String name=din.readLine();
   String branch=din.readLine();
   String sem=din.readLine();
   String cgpa=din.readLine();
   try {

   Class.forName("com.mysql.jdbc.Driver");
   } catch (ClassNotFoundException ex) {
   System.out.println("Unable to Load Class");
   }
   String url="jdbc:mysql://localhost/studentinfo";
   String userName="root";
   String password="root";
   try {

   conn=DriverManager.getConnection(url,userName,password);

   }

   catch (SQLException ex) {
   System.out.println("Unable to Connect to Database");
   }
   try {

   stmt=conn.createStatement();
   } catch (SQLException ex) {
   System.out.println("Unable to create Statment");
   }

   boolean sucessful = false;
   try {

   String query="Insert into student values (" +
   "'"+usn+"',"+
   "'"+name+"',"+
   "'"+branch+"',"+
   sem+","+cgpa+")";

   System.out.println("\nQuery Framed=="+query);
   sucessful = stmt.execute(query);
   System.out.println("Query executed sucessfully");


   } catch (SQLException ex) {
   System.out.println("Query not executed ");
   }




   } catch (IOException ex) {
   System.out.println("Unable to read data from keyboard");
   } finally {
   try {
   conn.close();
   } catch (SQLException ex) {
   System.out.println("Unable to close Connection");
   }
   }


   }
}

Tuesday, December 14, 2010

Difference between String s = "abc"; vs String s2 = new String("abc");

Naveen Mirajkar December 15 at 12:16am

/*
* NewMain.java
*
* Created on December 14, 2010, 11:43 PM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/

/**
*
* @author Naveen
*/
public class NewMain {

/** Creates a new instance of NewMain */
public NewMain() {
}

/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
String s1="abc";
String s2="abc";
/*
for these 2 above line in first for s1 runtime will create a new object and it is referenced by s1
4 nd line
already sequence of char "abc" is in mem pool at runtime so the java interpretor will not create a new object but to already exsisting object referred by s1 is assigned to s2
thats why when u use s1==s2 v use == wrt object to chech weather they are same or not wrt to memloc and their hashcode

in the line s3=new String("abc")
the runtime will create a new object in heap havin seq of chars "abc"

but
it has its own mem addr diff from s1 n s2
so if u use
s1==s3
it is false

but
s1.equals(s3)
is true coz v checkin the char seqncs in both the objs which r same

ok
i hope u got it..........*/

   String s4=s1;
   if(s1==s4) {
   System.out.println("Hi0");
   }
   if(s1.equals(s4)) {
   System.out.println("Hi00");
   }

   if(s1==s2) {
   System.out.println("Hi");
   }
   if(s1==s3) {
   System.out.println("Hello");
   }
   if(s1.equals(s2)) {
   System.out.println("Hi1");
   }
   if(s1.equals(s3)) {
   System.out.println("Hi2");
   }



   System.out.println(s1==s2); //true
   System.out.println(s1==s3); //false diff object identity
   System.out.println(s1.equals(s2)); //true
   System.out.println(s1.equals(s3)); //true

   System.out.println(System.identityHashCode(s1)); //they are
   System.out.println(System.identityHashCode(s2)); //the same object
   System.out.println(System.identityHashCode(s3)); //diff object



   }
}
output

Hi0
Hi00
Hi
Hi1
Hi2
true
false
true
true
4072869
4072869
1671711

JAVA N WEB TECH SYLLABUS

Thursday, December 23, 2010

Query result select * from customer

Query result

Wednesday, December 22, 2010

Tuesday, December 14, 2010