Java Programming

It seems that the number of allowed array dimensions is implementation specific and not set by the Java specifications. I'm sure that any Java implementation will allow a reasonable number of dimensions for any project you have.

After a quick test, it seems that Java is not limited by an arbitrary number so much as a practical value. If you add hundreds of array dimensions, Java will allow you to do so as long as you have enough memory allocated for Java. After a bit of copy-pasting the program no longer ran, exiting with a StackOverflowError.

The Main method is the method in which execution to any java program begins.

A main method declaration looks as follows:

public static void main(String args[]){

}

The method is public because it be accessible to the JVM to begin execution of the program.

It is Static because it be available for execution without an object instance. you may know that you need an object instance to invoke any method. So you cannot begin execution of a class without its object if the main method was not static.

It returns only a void because, once the main method execution is over, the program terminates. So there can be no data that can be returned by the Main method

The last parameter is String args[]. This is used to signify that the user may opt to enter parameters to the java program at command line. We can use both String[] args or String args[]. The Java compiler would accept both forms.

The symbol of java used as a hot cup because At the time of taking morning TEA JAMES GOSLIN got

a project which name was green project so thats why he uses the symbol of HOT CUP for JAVA.

An overloaded function is a function that has several implementations, the only difference being the number and type of parameters, including usage of the const keyword. Overloads cannot differ by return type alone. The following is a trivial example of function overloading.

const int & max(const int & lhs, const int & rhs){return( lhs>rhs ? lhs : rhs );}

const char & max(const char & lhs, const char & rhs){return( lhs>rhs ? lhs : rhs );}

Since the implementation is exactly the same, regardless of the type of parameters, it would make more sense to enlist the compiler to generate all the possible variants of this overloaded function using a template function. The compiler then generates all the overloads as required, and you only have one function to maintain.

Overloads are better suited to functions that have completely different signatures with a different number of parameters. For instance:

typedef struct rect_tag

{

float width;

float height;

} rect;

const float & Area( const rect & rc ){ return( rc.width * rc.height ); }

const int & Area( const int & width, const int & height ){ return( width * height ); }

const float & Area( const int & width, const float & height ){ return((float) width * height ); } const float & Area( const float & width, const int & height ){ return( width * (float) height ); }

The point of overloading functions is increased flexibility.You don't have to worry about which version of a function you call, nor is there any need to cast parameters to a specific type, since the compiler can work out which version of a function to call simply from the type of parameters you supply. If no suitable overload exists, the compiler will warn you so that you may either provide one, or explicitly cast your variables to a suitable version.

Mixing overloads with default parameter values increases the flexibility further, provided there is no ambiguity regarding which version of the overload is being called.

SIS files are Symbian and JAR files are java. The software that converts a SIS file to a JAR file is called Sis to Jar Converter 1.7.7.2.

When There is No Need to Change the Values of the Variables In Entire lifetime of That variables then we must use that Variable as Final Variable.

Linear list for example is array, linked list, stack, ...

It is called linear because all elements in those data structures are in linear sequence. We have first and the last elements in the list. If there is N elements in list, we know that all elements are in such sequence na, na+1.

Non-linear structures would be trees and graphs.

No such predefined type, so you can define it as you wish.

#include<iostream.h>

#include<conio.h>

void main()

{

int a, b, c;

clrscr();

cout<<"enter the two numbers";

cin>>a;

cin>b;

c=a+b;

cout<<"Addition of two numbers="<<c;

getch();

}

AWT stands for Abstract window toolkit. AWT gives us the components using which we can create User- Interface based applications in java. Some of the components are:

a. Frame

b. Panel

c. Window

d. CheckBox

e. RadioButton

f. Button

g. TextBox

h. TextArea

i. Etc

There are three types Java based applications.

1. Stand alone application: Where the application can be run on the machine where the code is available and the application is required on minimum one main method. Developed using J2SE API

Code has to be distributed to get the output

Eg: MSOffice

2. Web Application: Where the application is residing on some container and can be access from any where either from intranet or internet depends on the container exposed and cab developed using J2SE and J2EE

Eg: Any internet based applications like Facebook

Technology: Servlets and JSPs

Framework: Struts and Spring MVC

Architecture: MVC

Requirement: Webserver which has Servlet container and JSP Container

ie WebContainer = Servlet Container + JSP Container

Limitations: Supports only HTTP based requests

3. Enterpise Application: These are superset of Webapplications and with additional functionalities like more sophisticated for Business logic where applications needed more transactions ( DB interations) and security.

Technology: Servlets, JSP and EJBs

Frame Work: Any Frame work including Struts and Spring

Architecture: MVC-n tire

Requirement: EJB Container along with WebContainer

Advantages:

1. Protocol Independent

2. Fully Distributed

3. Full fledged business logic can be implemented with out any other frame works or tools like ORM

4. Supports JTA and JPA

#include
#include
#include
#include "2DArray.h"

#define GRAIN 1024 /* product size below which matmultleaf is used */

void seqMatMult(int m, int n, int p, double** A, double** B, double** C)
{
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
{
C[i][j] = 0.0;
for (int k = 0; k < p; k++)
C[i][j] += A[i][k]*B[k][j];
}
}


void matmultleaf(int mf, int ml, int nf, int nl, int pf, int pl, double **A, double **B, double **C)
/*
subroutine that uses the simple triple loop to multiply
a submatrix from A with a submatrix from B and store the
result in a submatrix of C.
*/
// mf, ml; /* first and last+1 i index */
// nf, nl; /* first and last+1 j index */
// pf, pl; /* first and last+1 k index */
{
for (int i = mf; i < ml; i++)
for (int j = nf; j < nl; j++)
for (int k = pf; k < pl; k++)
C[i][j] += A[i][k]*B[k][j];
}


void copyQtrMatrix(double **X, int m, double **Y, int mf, int nf)
{
for (int i = 0; i < m; i++)
X[i] = &Y[mf+i][nf];
}

void AddMatBlocks(double **T, int m, int n, double **X, double **Y)
{
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
T[i][j] = X[i][j] + Y[i][j];
}

void SubMatBlocks(double **T, int m, int n, double **X, double **Y)
{
for (int i = 0; i < m; i++)
for (int j = 0; j < n; j++)
T[i][j] = X[i][j] - Y[i][j];
}


void strassenMMult(int mf, int ml, int nf, int nl, int pf, int pl, double **A, double **B, double **C)
{
if ((ml-mf)*(nl-nf)*(pl-pf) < GRAIN)
matmultleaf(mf, ml, nf, nl, pf, pl, A, B, C);

else {
int m2 = (ml-mf)/2;
int n2 = (nl-nf)/2;
int p2 = (pl-pf)/2;

double **M1 = Allocate2DArray< double >(m2, n2);
double **M2 = Allocate2DArray< double >(m2, n2);
double **M3 = Allocate2DArray< double >(m2, n2);
double **M4 = Allocate2DArray< double >(m2, n2);
double **M5 = Allocate2DArray< double >(m2, n2);
double **M6 = Allocate2DArray< double >(m2, n2);
double **M7 = Allocate2DArray< double >(m2, n2);

double **A11 = new double*[m2];
double **A12 = new double*[m2];
double **A21 = new double*[m2];
double **A22 = new double*[m2];

double **B11 = new double*[p2];
double **B12 = new double*[p2];
double **B21 = new double*[p2];
double **B22 = new double*[p2];

double **C11 = new double*[m2];
double **C12 = new double*[m2];
double **C21 = new double*[m2];
double **C22 = new double*[m2];

double **tAM1 = Allocate2DArray< double >(m2, p2);
double **tBM1 = Allocate2DArray< double >(p2, n2);
double **tAM2 = Allocate2DArray< double >(m2, p2);
double **tBM3 = Allocate2DArray< double >(p2, n2);
double **tBM4 = Allocate2DArray< double >(p2, n2);
double **tAM5 = Allocate2DArray< double >(m2, p2);
double **tAM6 = Allocate2DArray< double >(m2, p2);
double **tBM6 = Allocate2DArray< double >(p2, n2);
double **tAM7 = Allocate2DArray< double >(m2, p2);
double **tBM7 = Allocate2DArray< double >(p2, n2);

copyQtrMatrix(A11, m2, A, mf, pf);
copyQtrMatrix(A12, m2, A, mf, p2);
copyQtrMatrix(A21, m2, A, m2, pf);
copyQtrMatrix(A22, m2, A, m2, p2);

copyQtrMatrix(B11, p2, B, pf, nf);
copyQtrMatrix(B12, p2, B, pf, n2);
copyQtrMatrix(B21, p2, B, p2, nf);
copyQtrMatrix(B22, p2, B, p2, n2);

copyQtrMatrix(C11, m2, C, mf, nf);
copyQtrMatrix(C12, m2, C, mf, n2);
copyQtrMatrix(C21, m2, C, m2, nf);
copyQtrMatrix(C22, m2, C, m2, n2);

// M1 = (A11 + A22)*(B11 + B22)
AddMatBlocks(tAM1, m2, p2, A11, A22);
AddMatBlocks(tBM1, p2, n2, B11, B22);
strassenMMult(0, m2, 0, n2, 0, p2, tAM1, tBM1, M1);

//M2 = (A21 + A22)*B11
AddMatBlocks(tAM2, m2, p2, A21, A22);
strassenMMult(0, m2, 0, n2, 0, p2, tAM2, B11, M2);

//M3 = A11*(B12 - B22)
SubMatBlocks(tBM3, p2, n2, B12, B22);
strassenMMult(0, m2, 0, n2, 0, p2, A11, tBM3, M3);

//M4 = A22*(B21 - B11)
SubMatBlocks(tBM4, p2, n2, B21, B11);
strassenMMult(0, m2, 0, n2, 0, p2, A22, tBM4, M4);

//M5 = (A11 + A12)*B22
AddMatBlocks(tAM5, m2, p2, A11, A12);
strassenMMult(0, m2, 0, n2, 0, p2, tAM5, B22, M5);

//M6 = (A21 - A11)*(B11 + B12)
SubMatBlocks(tAM6, m2, p2, A21, A11);
AddMatBlocks(tBM6, p2, n2, B11, B12);
strassenMMult(0, m2, 0, n2, 0, p2, tAM6, tBM6, M6);

//M7 = (A12 - A22)*(B21 + B22)
SubMatBlocks(tAM7, m2, p2, A12, A22);
AddMatBlocks(tBM7, p2, n2, B21, B22);
strassenMMult(0, m2, 0, n2, 0, p2, tAM7, tBM7, M7);

for (int i = 0; i < m2; i++)
for (int j = 0; j < n2; j++) {
C11[i][j] = M1[i][j] + M4[i][j] - M5[i][j] + M7[i][j];
C12[i][j] = M3[i][j] + M5[i][j];
C21[i][j] = M2[i][j] + M4[i][j];
C22[i][j] = M1[i][j] - M2[i][j] + M3[i][j] + M6[i][j];
}

Free2DArray< double >(M1);
Free2DArray< double >(M2);
Free2DArray< double >(M3);
Free2DArray< double >(M4);
Free2DArray< double >(M5);
Free2DArray< double >(M6);
Free2DArray< double >(M7);

delete[] A11; delete[] A12; delete[] A21; delete[] A22;
delete[] B11; delete[] B12; delete[] B21; delete[] B22;
delete[] C11; delete[] C12; delete[] C21; delete[] C22;

Free2DArray< double >(tAM1);
Free2DArray< double >(tBM1);
Free2DArray< double >(tAM2);
Free2DArray< double >(tBM3);
Free2DArray< double >(tBM4);
Free2DArray< double >(tAM5);
Free2DArray< double >(tAM6);
Free2DArray< double >(tBM6);
Free2DArray< double >(tAM7);
Free2DArray< double >(tBM7);
}
}

void matmultS(int m, int n, int p, double **A, double **B, double **C)
{
int i,j;
for (i=0; i < m; i++)
for (j=0; j < n; j++)
C[i][j] = 0;
strassenMMult(0, m, 0, n, 0, p, A, B, C);
}


int CheckResults(int m, int n, double **C, double **C1)
{
#define THRESHOLD 0.001
//
// May need to take into consideration the floating point roundoff error
// due to parallel execution
//
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
if (abs(C[i][j] - C1[i][j]) > THRESHOLD ) {
printf("%f %f\n", C[i][j], C1[i][j]);
return 1;
}
}
}
return 0;
}



int main(int argc, char* argv[])
{
clock_t before, after;

int M = atoi(argv[1]);
int N = atoi(argv[2]);
int P = atoi(argv[3]);

double **A = Allocate2DArray< double >(M, P);
double **B = Allocate2DArray< double >(P, N);
double **C = Allocate2DArray< double >(M, N);
double **C4 = Allocate2DArray< double >(M, N);

int i, j;

for (i = 0; i < M; i++) {
for (j = 0; j < P; j++) {
A[i][j] = 5.0 - ((double)(rand()%100) / 10.0);
}
}

for (i = 0; i < P; i++) {
for (j = 0; j < N; j++) {
B[i][j] = 5.0 - ((double)(rand()%100) / 10.0);
}
}

printf("Execute Standard matmult\n\n");
before = clock();
seqMatMult(M, N, P, A, B, C);
after = clock();
printf("Standard matrix function done in %7.2f secs\n\n\n",(float)(after - before)/ CLOCKS_PER_SEC);

before = clock();
matmultS(M, N, P, A, B, C4);
after = clock();
printf("Strassen matrix function done in %7.2f secs\n\n\n",(float)(after - before)/ CLOCKS_PER_SEC);

if (CheckResults(M, N, C, C4))
printf("Error in matmultS\n\n");
else
printf("OKAY\n\n");

Free2DArray(A);
Free2DArray(B);
Free2DArray(C);
Free2DArray(C4);

return 0;
}

You don't need to write a program to do this. Each character (char) is actually an int. If you want to see the ASCII value of a char you can simply:

char c = 'a';

System.out.print( (int)c );

No args means no arguments. Just like any regular method, a constructor can have zero or more arguments.

No args means no arguments. Just like any regular method, a constructor can have zero or more arguments.

No args means no arguments. Just like any regular method, a constructor can have zero or more arguments.

No args means no arguments. Just like any regular method, a constructor can have zero or more arguments.

knioubuhy yig hnm vuigvgh ujhb jhbihjbnihkjlkmmnlk

1) List the eight basic data types used in Java. Give examples. The basic types are also known as primitive types and when a variable is declared as any of them, the computer creates what you can call a 'box' in its memory that is big enough to hold a value of that type. Eg int x; // at runtime, computer creates a box called 'x' big enough to hold an integer an integer can be anything between -2147483638 to 2147483647 the other seven primitive (or basic) data types are byte - anything between -128 to 127 short - anything between -32768 to 32767 long - anything between -9223372036854775808 to 9223372036854775807 float - anything between -1.4 * 10^-45 to 3.4 * 10^38 double - anything between -4.9 * 10^-324 to 1.8 * 10^308 char - any single digit on your keyboard (unicode) boolean - true or false source: charatan and kans Java in two semesters pg 19

High-level source code is converted to native machine code either by an interpreter or a compiler. Interpreted code requires a runtime in order to perform the conversion each time the program is executed whereas compiled code typically produces a standalone machine code program that can be executed without further interpretation. There are some exceptions, most notably Java which is first compiled to Java byte code which is then interpreted by the Java virtual machine on each execution.

An interpreter always converts high-level code to native machine code but, because it must perform the conversion while the code is executing via the interpreter, interpreted code executes much more slowly than native machine code.

Technically, a compiler is simply a program that converts high-level code to a lower-level code. That lower-level code could be another high-level language. For example, a C++ source could be compiled to produce a C source. However, converting the other way around (such as from C to C++) can only be done manually because humans can think in abstract terms far more easily than machines can.

Low-level assembly language source are converted to machine code using an assembler. Machine code can also be disassembled to produce an assembly-like source known as a disassembly, however the resultant code is extremely low-level because there are no named variables (only memory offsets) and all user-comments will have been stripped out during assembly or compilation.

No. Interface variables are supposed to be public static final. Interfaces, like abstract classes, cannot be instantiated, so all variables in an interface must be static final ones. They are public because usually interfaces are used throughout an application, and this will ensure versatility.

An Adapter is simply a concrete class which implements all the methods of a Listener interface as empty functions. They are convenience classes made because of the tendency to implement Listeners as anonymous classes.

For example, let's say we want to add a Listener to a JFrame to detect a mouse click:

// implementing a Listener

JFrame frame = new JFrame();

frame.addMouseListener(new MouseListener() {

void mouseClicked(MouseEvent e) {

// do something here

}

void mouseEntered(MouseEvent e) {

}

void mouseExited(MouseEvent e) {

}

void mousePressed(MouseEvent e) {

}

void mouseReleased(MouseEvent e) {

}

});

Note how this has a lot of extra code that does nothing.

// implementing an Adapter

JFrame frame = new JFrame();

frame.addMouseListener(new MouseAdapter() {

void mouseClicked(MouseEvent e) {

// do something here

}

});

Note now how we only need to implement one method. This is much cleaner and easier to read.

You download Rmi Updater then load it on and update it and then its done boom!

void main()
{ char a[30],b[30];
int i,j,f=1;
printf("\nEnter a string");
gets(a);
for(i=0;a[i]!=\0;i++);
for(j=0;i!=0;i--)
{ b[j++]=a[i];
}
b[j]=\0;
for(i=0;a[i]!=\0;i++)
{ if(a[i]!=b[i])
{ f=0;
break;
}
}
if(f==0)
printf("NOT PALINDROME");
else
printf("PALINDROME");
getch();
}
Syntax error may happen.