Java Programming

* byte: The byte data type is an 8-bit signed two's complement integer. It has a minimum value of -128 and a maximum value of 127 (inclusive). The byte data type can be useful for saving memory in large arrays, where the memory savings actually matters. They can also be used in place of int where their limits help to clarify your code; the fact that a variable's range is limited can serve as a form of documentation. * short: The short data type is a 16-bit signed two's complement integer. It has a minimum value of -32,768 and a maximum value of 32,767 (inclusive). As with byte, the same guidelines apply: you can use a short to save memory in large arrays, in situations where the memory savings actually matters. * int: The int data type is a 32-bit signed two's complement integer. It has a minimum value of -2,147,483,648 and a maximum value of 2,147,483,647 (inclusive). For integral values, this data type is generally the default choice unless there is a reason (like the above) to choose something else. This data type will most likely be large enough for the numbers your program will use, but if you need a wider range of values, use long instead. * long: The long data type is a 64-bit signed two's complement integer. It has a minimum value of -9,223,372,036,854,775,808 and a maximum value of 9,223,372,036,854,775,807 (inclusive). Use this data type when you need a range of values wider than those provided by int. * float: The float data type is a single-precision 32-bit IEEE 754 floating point. Its range of values is beyond the scope of this discussion, but is specified in section 4.2.3 of the Java Language Specification. As with the recommendations for byte and short, use a float (instead of double) if you need to save memory in large arrays of floating point numbers. This data type should never be used for precise values, such as currency. For that, you will need to use the java.math.BigDecimal class instead. Numbers and Strings covers BigDecimal and other useful classes provided by the Java platform. * double: The double data type is a double-precision 64-bit IEEE 754 floating point. Its range of values is beyond the scope of this discussion, but is specified in section 4.2.3 of the Java Language Specification. For decimal values, this data type is generally the default choice. As mentioned above, this data type should never be used for precise values, such as currency. * boolean: The boolean data type has only two possible values: true and false. Use this data type for simple flags that track true/false conditions. This data type represents one bit of information, but its "size" isn't something that's precisely defined. * char: The char data type is a single 16-bit Unicode character. It has a minimum value of '\u0000' (or 0) and a maximum value of '\uffff' (or 65,535 inclusive).

Java Server Pages have become an integral part of any J2EE application. They are used extensively because they can combine the features of HTML and Java. The difficulty level of JSP is half-way between HTML and pure Java. For simple tasks like displaying the current date, you write a normal HTML page and add only a small amount of Java as a scriptlet. For big tasks like processing a shopping cart, you use JSP as the mediator between the Web form and a component (Ex: Servlet) that has all the processing logic.

CGI, Perl, Active Server Pages etc were all the predecessors of Java Server Pages. Am not saying that the JSP Technology was built based on these technologies but it is safe to say that, the JSP Technology was created to overcome many of the shortcomings in the above mentioned technologies. Though the ASP technology is a web server scripting champion and is used very widely, the only problem is the Runs only in Windows Attitude of the technology. Unlike ASP, JSP has equivalent if not better features and can run in any environment making it an invaluable tool for enterprise application developers who don't want to be tied to the limitation of the system running only in Windows.

Not only does JSP run on all major platforms, but the JavaBeans used by these JSPs run on all major platforms as well.

JSP competes directly with ASP. In fact, you would be forgiven if you thought it was a copy. Sun took the same approach to JSP as it did with Java. Sun borrowed the syntax of its best competitor (ASP for JSP and C++ for Java) tweaked it a little, but built everything under the hood from scratch. Java syntax comes from C++, but it works on all platforms with no portability issues like C++ for the developer. Similarly, the JSP structure comes from ASP. The look and feel, and even some syntax is the same. However, ASP primarily uses Microsoft's versatile VBScript, while JSP uses the more powerful and portable Java and JavaScript.

Less access to technology and I'm assuming less knowledge of it as well

This functionality is already in Java. String.toLowerCase() and String.toUpperCase() will take care of it for you.

import java.io.*;
class PerfectPalindrome
{
private boolean per(int a)
{
int b=0,c=1;
for(;c<=(a/2);c++)
{
if(a%c==0)
{
b+=c;
}
}
if(a==b)
return true;
else
return false;
}
private boolean pal(int a)
{
int b=a,c=0;
for(;b>0;b/=10)
{
int d=b%10;
c=(c*10)+d;
}
if(c==a)
return true;
else
return false;
}
public static void main()throws IOException
{
BufferedReader in=new BufferedReader(new InputStreamReader(System.in));
System.out.println("1. Find a number is a perfect one or not !");
System.out.println("2. Find a number is a palindrome or not !");
System.out.print("\nEnter your Choice: ");
int a=Integer.parseInt(in.readLine()),c;
System.out.print("Enter the Number: ");
c=Integer.parseInt(in.readLine());
boolean b;
PerfectPalindrome e=new PerfectPalindrome();
switch(a)
{
case 1: b=e.per(c);
if(b==true)
System.out.print("It is a Perfect Number !");
else
System.out.print("It is not a Perfect Number !");
break;
case 2: b=e.pal(c);
if(b==true)
System.out.print("It is a Palindrome Number !");
else
System.out.print("It is not a Palindrome Number !");
break;
default: System.out.print("SORRY!! Wrong Choice!");

C itself does not support default values for function arguments, if that is your definition of parameter.

In languages that do, like C++/python/ and Java (presumably) you can use default parameters as a rudimentary form of polymorphism in the sense that you can call the function or method with a minimal set of arguments assuming the that others are defaulted to the values you want, this can be actual defaulted values like the number -1, or sentinel values that omit functionality in the function/method you are calling.

You will, in most of these languages that support this, have to arrange the position of the defaulted arguments to the end of the argument list, and in doing so it would be best to prioritize them from least likely to use the default value to the most from left to right. This in design time can conflict with function/method overloading where you vary the number of arguments in the prototypes of your overloaded function, so I consider these two features of a language mutually exclusive, i.e. don't use them together unless you have a good reason.

This feature is rarely useful but in saying "rarely" when it is, it is the most helpful. I find it and so do the creators of the C++ libraries helpful for class constructors when sometimes you need to set some internal features during construction time.

The Java Development Kit (JDK) is a command-line based application. That means it is run through the command prompt. The usage of this is similar with all platforms, however for each operating system it is different.

For Windows, go to Start -> Programs (All programs on XP) -> Accessories -> Command Prompt. It will show a black screen in which you type commands in.

For Macs, go to Applications -> Utilities -> Terminal

In the prompt, type 'java' or 'javac'. As the compiler is 'javac', you may need to add an enviornmental variable to point to the location of Java (javafolder/bin/javac.exe)

Functions are used to carryon a specific task or to perform specific operation.

While older slot machines used a mechanical/mathematical approach (the number of icons on each wheel, combined with the required combination of those to yield various winning matches), today's typical slot machine are completely computerized. They generate thousands of random combinations per second, and when you pull the handle (or push the button), the cycle stops and you get the number it was up to. The handle, the slowing-down of the wheels, etc., are there simply for historical purposes.

"Single core" refers to the computer's main chip having a single processor. Newer models, such as Intel's i3, i5 and i7, have multiple processors (2, 4, or 6 processors), usually called multiple "cores", on a single chip.

GHz refers to the clock speed of each individual processor. It gives you a rough idea of how fast it can process data. However, the processing speed will also depend on other factors.

Because the developers of Java considered the possibility of multithreading a big advantage. You don't HAVE TO use multiple threads; just use it when you need it.

Because the developers of Java considered the possibility of multithreading a big advantage. You don't HAVE TO use multiple threads; just use it when you need it.

Because the developers of Java considered the possibility of multithreading a big advantage. You don't HAVE TO use multiple threads; just use it when you need it.

Because the developers of Java considered the possibility of multithreading a big advantage. You don't HAVE TO use multiple threads; just use it when you need it.

A variable declared as final can't be modified, once a value is assigned.

A default constructor is one that has no parameters (C++ also calls constructors with all default parameters a default constructor), while a parameterized constructor is one that has at least one parameter without a default value. Default constructors can be provided by the compiler if no other constructors are defined for that class or any class the class inherits from, while parameterized constructors must always be defined by the developer.

It means that the method is visible from only within the current method. Also, any class that wants to use or invoke the private method has to create an object of the class in which the method is created in order to access/invoke it. The private access modifier is the most restrictive of the four java access modifiers. The total opposite of private is public which gives access to everyone.

1. It should be simple and clear, any tester should be able to understand it reading once.
2. Should be accurate and tests what it is intended to test.
3. No unnecessary steps should be included.
4. It should be reusable.
5. It should be traceable to requirements.
6. It should be independent. i.e. You should be able to execute it in any order without any dependency on other test cases.

yes, it is

It is used import your scanner class. In other words bringing in the scanner class.

you can easily disable java in almost all of the web browsers! I just came across this article telling how to disable java in different browser, check this out :

http://studyabroadfree.com/how-to-disable-java-in-browsers-after-us-cert-warning/

By reference. The name of the string is converted to a pointer (in C/C++) and given to the function as the address of the first element. (In Java, all objects are passed by reference, and there are no pointers.)

• Interfaces are classes that help us in implementing partial Multiple Inheritance in Java.
• It helps us in defining skeleton behavior for our classes.
• Also, it is used for creating classes that store application level constants

Java byte-code is the code which generate after the compilation of .java file.And this code is only understand by JVM(java virtual machine ) which understand it and execute it.In other languages this type of functionality is not available.

Yes. Most operating systems have some form of Java for them.

This is concerned with looking into the commonality of some elements. Best used with status study.