Remove Numbers in String - Java Program

public String removeNumbersInString(String str) {

        String temp = "";

        String regexp = "^[0-9]";

        Pattern pattern = Pattern.compile(regexp);

        Matcher matcher;

        if(!str.isEmpty()){

        for (int i = 0; i < str.length(); i++) {

            matcher = pattern.matcher(str.charAt(i) + "");

            if (!matcher.matches()) {

                temp = temp + str.charAt(i) + "";

            }

        }}

        System.out.println("" + temp);

        return temp;

    }

Remove String in Numbers-Java Program

public String removeStringInNumbers(String str) {

        String temp = "";

        String regexp = "^[a-zA-Z]";

        Pattern pattern = Pattern.compile(regexp);

        Matcher matcher;

        if(!str.isEmpty()){

        for (int i = 0; i < str.length(); i++) {

            matcher = pattern.matcher(str.charAt(i) + "");

            if (!matcher.matches()) {

                temp = temp + str.charAt(i) + "";

            }

        }}

        System.out.println("" + temp);

        return temp;

    }

Write an example that counts the number of times a particular character, such as e, appears in a file. The character can be specified at the command line.

import java.io.BufferedInputStream;
import java.io.FileInputStream;

class GetOccurrences{
    public static void main(String args[])
    {
        try{
            FileInputStream fis=new FileInputStream("C:\\Users\\SAN-MCA-ME-MTECH-MS\\Documents\\SAN\\Temp.txt");
            BufferedInputStream bis=new BufferedInputStream(fis);
                    
            int i;
            int occurs=0;
            
            while((i=bis.read())!=-1)
            {
                char a=(char)i;
                
                if(a==args[0].charAt(0))
                {
                 occurs++;
                }
            }
            System.out.println("Letter e  is "+occurs+" of times repeated in the file");
        }catch(Exception ex)
        {
            System.out.println(ex.getMessage());
        }
    }
}

Java Connect to Oracle XE Database

 

In order to connect to oracle  database you need to add ojdbc14.jar file in your eclipse project as a external jar file.... Download from web.

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class OracleConnect {

    /**
     * @param args
     */
    public static void main(String[] args) throws IOException{
        // TODO Auto-generated method stub
        try
        {
        Class.forName("oracle.jdbc.driver.OracleDriver");
        Connection con = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:xe","saravanan","saravanan");
        System.out.println("Connected Successfully To Oracle");
        Statement stmt;
        ResultSet rs;
        stmt=con.createStatement();
        rs=stmt.executeQuery("select * from saran");
        
       while(rs.next())
       {
            System.out.println(rs.getString("empname")+"--"+rs.getInt("salary"));
       }
        
        
        }
        catch(Exception ex)
        {
        ex.printStackTrace();
        }

    }

}

Simple java program for connecting to DATABASE(mysql)

In order to connect to database you need to add mysql-connector-java-5.1.22.jar file in your eclipse project as a external jar file....

import java.sql.Connection;

import java.sql.Driver;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;



public class SqlSample {



    /**

     * @param args

     * @throws ClassNotFoundException 

     * @throws IllegalAccessException 

     * @throws InstantiationException 

     * @throws SQLException 

     */

    public static void main(String[] args) throws InstantiationException, IllegalAccessException, ClassNotFoundException, SQLException {

        // TODO Auto-generated method stub

        Connection con;

        Class.forName("com.mysql.jdbc.Driver");

        con = DriverManager.getConnection("jdbc:mysql://localhost/saran","root","root");

        Statement stmt;

        ResultSet rs;

        stmt=con.createStatement();

        rs=stmt.executeQuery("select * from employee;");

        

        while(rs.next())

        {

            System.out.println(rs.getString("empname")+rs.getInt("salary"));

        }

    }



}

Servlet Program for Retrieving data from Table

In order to connect to database you need to add mysql-connector-java-5.1.22.jar file in your eclipse project as a external jar file.... 

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;



/**

 * Servlet implementation class HelloServlet

 */

import java.io.*;



import javax.servlet.*;

import javax.servlet.http.*;



import java.sql.*;



public

    class HelloServlet extends HttpServlet {

    

    public void doGet (HttpServletRequest req, HttpServletResponse res)

        throws ServletException, IOException {

        res.setContentType("text/html");

        

        PrintWriter out=res.getWriter();

        out.println("<html>");

        out.println("<head><title>Students List</title></head>");

        out.println("<body>");

        

        try {

        // The newInstance() call is a work around for some

        // broken Java implementations

        

        Class.forName("com.mysql.jdbc.Driver").newInstance();

        }

        catch (Exception E) {

        out.println("Unable to load driver.");

        E.printStackTrace();

        }

        

        out.println("<br><center><p style=color:purple;font-size:30px;>STUDENTS DATABASE</p></center><hr>");

        

        try {

        Connection Conn = 

            DriverManager.getConnection("jdbc:mysql://localhost/saran","root","root");

            

        // Do something with the Connection

        Statement Stmt = Conn.createStatement();

        ResultSet RS = Stmt.executeQuery("SELECT * from student");

        out.println("<center><table border='1' style=color:purple;font-size:20px;><th>Name</th><th>Area</th><th>Course</th>");

        while (RS.next()) {

            out.println("<tr><td>"+RS.getString("name")+"<td>"+RS.getString("area")+"<td>"+RS.getString("course")+"</td></tr>");

            

        }

        out.println("</table></center>");

        out.println("<center><form action='index.htm'><input type='submit' value='Home'></form></center>");

        // Clean up after ourselves

        RS.close();

        Stmt.close();

        Conn.close();

        

        }

        catch (SQLException E) {

        

        }

        

        

        out.println("</body></html>");

    }

    

    }

Compare Two Integer Arrays

This program will compare two integer arrays and return a result number of matching numbers in those arrays :
public void arrayMatcher(int a[], int b[])
{
   
    int count=0;
    for(int i=0;i<a.length;i++)
    {
        for(int j=0;j<b.length;j++)
        {
            if((a[i])==(b[j]))
            {
                count++;
   
            }
        }
       
    }
    System.out.println(count+" numbers matches in two arrays");
   
   
} 
CONTENT WARNING:This is my own program.. It is for Educational purposes only. Please do not republish or reproduce with another name in online.