Sunday, May 25, 2014

this keyword in Java

this keyword

Here is given the usage of this keyword.


  • this keyword can be used to refer current class instance variable.
  • this() can be used to invoke current class constructor.
  • this keyword can be used to invoke current class method (implicitly)
  • this can be passed as an argument in the method call.
  • this can be passed as argument in the constructor call.
  • this keyword can also be used to return the current class instance.

    From - www.DreamsCoder.com
  • Wednesday, May 14, 2014

    Star Pattern Program in C




    /*Star Pattern Program in C

    Author - Chinmay Mahajan*/


    #include<stdio.h>
    #include<conio.h>

    void main()
    {
    int i,j,k,m,o,f,n;
    clrscr();
    printf("Enter value of n \n");
    scanf("%d",&n);
    k=n;
    o=1;
    for(i=0;i<n;i++) //for number of lines
    {

    for(j=0;j<k;j++) //for left spacing
    {
    printf("_");
    }
    for(m=0;m<o;m++) //for Printing *
    {
    printf(" *");
    }

    for(f=0;f<k;f++)  //for right spacing
    {
    printf("_");
    }
    printf("\n"); //new line
    k--;
    o++;
    }//outer for
    }//main

    Sunday, April 20, 2014

    Socket Programming with File Handling

    /*Client Socket program that accepts file name from Client and send it to Server, Server Side Socket reads the Content of a file and display them onto the Client Socket*/

    /*Server Program (severprac.java)*/


    import java.io.*;
    import java.net.*;

    public class serverprac
    {

    public static void main(String[] args) {

    ServerSocket ss;
    Socket client;
    String nm;
    try
    {
    ss = new ServerSocket(1212);
    System.out.println("Server is Waitng For Client");
    client = ss.accept();
    System.out.println("Client is Connected");
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    BufferedReader br1 = new BufferedReader(new InputStreamReader(client.getInputStream()));
    PrintStream ps = new PrintStream(client.getOutputStream());

    String filenm = br1.readLine();

    File f = new File(".");
    File[] flist = f.listFiles();

    for(File n:flist)
    {
    nm = n.getName();
    if(nm.equals(filenm))
    {

    System.out.println("File is Present");
    FileReader fr = new FileReader(nm);
    BufferedReader bfr = new BufferedReader(fr);
    String lne;
    while(true)
    {


    lne = bfr.readLine();

                    if (lne == null)
                    break;
    //System.out.println(lne);

    ps.println(lne);
    }
    }
    }


    ps.close();
    br1.close();
    br.close();
    ss.close();

    }//try
    catch(Exception e)
    {
    System.out.println(e);
    }
    }//main
    }

    /*Client Program (clientprac.java)*/

    import java.io.*;
    import java.net.*;

    public class clientprac
    {

    public static void main(String[] args)
    {
    Socket s;
    try
    {
    s = new Socket("127.0.0.1",1212);
    System.out.println("Clent is Conneccted to the Server");

    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    BufferedReader br1 = new BufferedReader(new InputStreamReader(s.getInputStream()));
    PrintStream ps = new PrintStream(s.getOutputStream());
    System.out.println("Enter File name");
    ps.println(br.readLine());
    while(br1.readLine() !=null)
    System.out.println(br1.readLine());
    br1.close();
    ps.close();
    br.close();
    br1.close();
    s.close();

    }
    catch(Exception e)
    {
    System.out.println(""+e);
    }//catch
    }//main
    }

    Saturday, March 29, 2014

    Inter - Thread communication using wait(), notify() and notify all() method in Java

    /*
    Write a program to illustrate  inter - thread communication using wait(), notify() and notify all() method
    */

    import java.io.*;
    class q
    {
    String msg;
    boolean flag;
    q()
    {
    flag=false;
    }
    synchronized void get()
    {
    if(flag==false)
    {
    try
    {
    wait();
    }//try
    catch(InterruptedException e)
    {

    }//catch

    }
    flag=false;
    System.out.println("Received Message"+msg);
    notify();
    }
    synchronized void put(String x)
    {
    if(flag==true)
    {
    try
    {
    wait();
    }
    catch(InterruptedException e)
    {

    }//catch

    }
    msg = x;
    flag = true;

    if(msg.equalsIgnoreCase("Good Bye"))
    System.exit(0);
    notify();
    }
    }


    class sender extends Thread{
    q q1;
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String s;
    sender(q x)
    {
    q1 = x;
    start();
    }
    public void run()
    {
    while(true)
    {
    System.out.println("Enter Message ");
    try
    {
    s = br.readLine();
    q1.put(s);
    }
    catch(IOException e)
    {

    }//catch
    }//while
    }//run
    }

    class receiver extends Thread
    {
    q q2;
    receiver(q x)
    {
    q2 = x;
    start();

    }

    public void run()
    {
    while(true)
    {
    q2.get();
    }
    }
    }

    class fourteen
    {
    public static void main(String args[])
    {
    q q4 = new q();
    sender s = new sender(q4);
    receiver r = new receiver(q4);
    }
    }

    User Defined Exception Example in Java

    /*
    Write a class Student with attributes roll no, name, age and course. Initialize values through parameterized constructor. If age of student is not in between 15 and 21 then generate user-defined exception “Age Not Within The Range”.If name contains numbers or special symbols raise exception “Name not valid
    */

    import java.io.*;
    class AgeNotWithinRangeException extends Exception
    {
    AgeNotWithinRangeException()
    {
    super();
    }
    }

    class NameNotValidException extends Exception
    {
    NameNotValidException()
    {
    super();
    }
    }
    class Student
    {
    private
    int roll,age;
    String name,course;

    public
    Student(int r,String nm,int ag,String co)
    {
    roll=r;
    name=nm;
    age=ag;
    course=co;

    System.out.println("Roll Number is "+roll);
    System.out.println("Name is "+name);;
    System.out.println("Age is "+age);
    System.out.println("Course is "+course);
    }

    public static void main(String args[]) throws IOException
    {

    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    int roll,age;
    String name,course;
    System.out.println("Enter No. :");
    roll = Integer.parseInt(br.readLine());
    System.out.println("Enter Name :");
    name = br.readLine();
    try
    {
    for(int i=0;i<name.length();i++)
    {
    char c = name.charAt(i);

    if((c<65 || c>90) && (c<97 || c>122) && (c!=32))
    {
    throw new NameNotValidException();
    }//if
    }//for
    }//try
    catch(NameNotValidException n)
    {
    System.out.println("Invalid Name"+n);
    }
    System.out.println("Enter Age :");
    age = Integer.parseInt(br.readLine());
    try
    {
    if(age<15 || age>21)
    {
    throw new AgeNotWithinRangeException();
    }
    }//try

    catch(AgeNotWithinRangeException e)
    {
    System.out.println("Invalid Age"+e);
    }

    System.out.println("Enter Course :");
    course = br.readLine();

    Student s = new Student(roll,name,age,course);
    }
    }

    Friday, March 28, 2014

    Error while Creating New Android Project in Eclipse.

    Problem with Eclipse while creating New Android Application 


    Solution - In Eclipse go to Window - > Android SDK Manager 
    Select one or more SDK Platform and Install them.
    Also Update ADT plugins.

    Thursday, January 23, 2014

    University Rankings For MS in Computer Science (CS) 2013

    RankUniversities
    1Carnegie Mellon University
    2Massachusetts Institute of Technology
    3Stanford University
    4University of California, Berkeley
    5Cornell University
    6University of Illinois, Urbana-Champaign
    7University of Washington
    8Princeton University
    9University of Texas, Austin
    10Georgia Institute of Technology
    11California Institute of Technology
    12University of Wisconsin, Madison
    13University of Michigan, Ann Arbor
    14University of California, Los Angeles
    15University of California, San Diego
    16University of Maryland, College Park
    17Columbia University
    18Harvard University
    19University of Pennsylvania
    20Brown University
    21Purdue University, West Lafayette
    22Rice University
    23University of Massachusetts, Amherst
    24University of North Carolina, Chapel Hill
    25University of Southern California
    26Yale University
    27Duke University
    28Johns Hopkins University
    29New York University
    30Ohio State University
    31Pennsylvania State University
    32Rutgers, the State University of New Jersey
    33University of California
    34University of Virginia
    35Northwestern University
    36University of California
    37University of Chicago
    38University of Minnesota
    39University of California
    40University of Colorado
    41University of Florida
    42University of Utah
    43Washington University in St. Louis
    44Dartmouth College
    45Stony Brook University
    46Virginia Tech
    47Boston University
    48North Carolina State University
    49Rensselaer Polytechnic Institute
    50Texas A&M University
    51University of Arizona
    52University of Rochester
    53Arizona State University
    54Indiana University
    55University of California
    56University of California
    57University of Pittsburgh
    58Michigan State University
    59University of Illinois
    60Vanderbilt University
    61Northeastern University
    62University at Buffalo
    63Case Western Reserve University
    64George Mason University
    65Iowa State UniversityOregon State University
    66Syracuse University
    67University of Iowa
    68University of Notre Dame
    69University of Oregon
    70University of Tennessee
    71Brandeis University
    72Naval Postgraduate School
    73Polytechnic Institute of New York University
    74Tufts University
    75University of Connecticut
    76University of Delaware
    77University of Maryland
    78Clemson University
    79College of William and Mary
    80Colorado State University
    81CUNY Graduate School and University Center
    82Florida State University
    83George Washington University
    84Oregon Health and Science University
    85University of Kansas
    86University of Nebraska
    87University of New Mexico
    88University of Texas
    89Washington State University
    90Auburn University
    91Brigham Young University
    92New Jersey Institute of Technology
    93University at Albany
    94University of Central Florida
    95University of Georgia
    96University of Kentucky
    97Worcester Polytechnic Institute
    98Drexel University
    99Georgia State University
    100Kansas State University
    101Lehigh University
    102Louisiana State University
    103Stevens Institute of Technology
    104University of Cincinnati
    105University of North Carolina
    106University of South Carolina
    107University of South Florida
    108University of Texas
    109Binghamton University
    110Colorado School of Mines
    111Illinois Institute of Technology
    112Southern Methodist University
    113Temple University
    114University of Houston
    115University of Missouri
    116University of Oklahoma
    117University of Wisconsin
    118Wayne State University
    119West Virginia University
    120Claremont Graduate University
    121Mississippi State University
    122Missouri University of Science & Technology
    123New Mexico State University
    124Texas Tech University
    125Wright State University