Java Tutorial #7

The Java's Scanner


Java Scanner is used to store variables and string you inputted in the console.  For example, the program requires you to put/type any number.  The string or the number you inputted in the console is being stored by the the Scanner.  So that later your program can access the data you inputted.  In able to use the Scanner you must import it to your Program (at the top part of your program see the first picture below) just type "import java.util.Scanner;".

Now, you have imported the Scanner in your program, you can now assign a name into that Scanner just type the word "Scanner scannername = new Scanner(System.in);". Note that you can have any name for the scannername.  Any character is qualify for a ScannerName.  

Now, we created a new Scanner.  The question is how we can access the data inside it.
In order to access information inside that scanner, first call the variable you stored to that scanner, put the equal sign then second put the scannername ,put the dot symbol (.) and type one of the ff keyword 

nextLine( );  --->  If variable is a String or a Character.
next( ); ---->  If you want to leave the cursor the last letter of the String.
nextInt( ); --->  If the variable is an Integer.
nextDouble( ); --->  If the variable is a float/double Value.

(ex. variable = scannername.nextInt( ); if the variable is an Integer)

For example, a program that will ask you to enter your name and then it will output the greeting "Hello " plus your name.  Later, your name will be stored in the Scanner then the program will access/process the information you inputted and add the word "Hello  " to it. Consider this example.

Java Tutorial #6

More of Math Class Function in Java Programming

Build in Function for Ceiling and Floor Value
  Math.ceil(value); , Math.floor(value); is the reserved words for finding the ceiling and the floor value.  This is also known as nearest value function.  This can find the nearest up and down value of a number.  Consider the example below.

Build in Function for Power
   One of the commonly used function in Java is the Power function.  Usually used for exponential functions and inverse function mainly concerned for trigonometry functions.  Math.pow(base, exponent); is the reserved word for it.  See example below.

Build in Function for Square Root
    Also the same with the Power function this is one of the easiest yet most applicable function widely used today.  Mainly this is concerned for different mathematical computation.  Math.sqrt(value); is the reserved word for it.

You can now explore some of the Math class by using them one by one. Hope this topic helps you out.

Java Tutorial #5

Different Math Class in Java


This topic will include multiple Math Class Function that is very applicable to Java Programming.  There are so many Math Class Function to Java Programming but I will only mention some of it (The Function that very commonly use to some applications).  So, Let get Started.

Build in Function for PI = 3.1416;
   Math.PI*value is a reserved keyword in Java.  This keyword will automatically initialize the nearest value of PI.  This is commonly used keyword for finding the Area, the circumference, and volume of different circular figures.  Consider the first bunch of codes in the program.

Build in Function for Absolute Value
    Math.abs(value) is also a reserved word in Java Programming. This keyword will automatically omit the negative signs to your integer.  It will convert the negative integer into positive.  Look for the second group of codes inside the program below.

Build Function for Maximum and Minimum
    This Function will take two arguments.  The two value you want to compare.  You can assign the value to a variable or you can directly type it.  Math.max(value1, value2) for maximum and Math.min(value1, value2) for minimum.

Java Tutorial #4

The .replace( ) Function in Java


This is one of the easiest yet the most commonly used keyword in Java.  It is used to replace a character or a group of String to an existing String.  This function will take two arguments.  The first argument is the OLD CHARACTER you want to replace with.  The second argument is the NEW CHARACTER/WORD that will replace the old/existing group of String/character.

START------->
Consider this example.  Like I said a while ago, this is one of the easiest function so I don't have to spend more word for it.  The explanation is the comment inside the program.  Read those green lines then later you will get it.

I hope you get it. For questions,  you can put it to the comment box below this one. Thanks.

Java Tutorial #3

The toUpperCase() and the toLowerCase() Function in Java

The two functions is use to output or to display a string in a Lowercase or in the Uppercase. So, Let us make use of it..!

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I think it is a SELF EXPLANATORY FUNCTION so I will not spend more time to it.  I will show you some example then BOOM you will come up to the I GET IT state. 

Java Tutorial #2

The Two ways to do a Process of Concatenation
This article will show you the two concatenation process available and valid to Java.  One way is by using a symbol "+" and the other way is by using the ".concat( )" method.  You will later know what is the difference between the two.

START----->

The "+" symbol is using by the concatenation operation.  It is use to concat (combine) two strings, variables, characters and others. In the previous program we make sense the use of the "+" symbol.  We use the "+" symbol the combine the string "n1 is " and the value of the variable n1.  (We don't want to spend more time hark backing some things that uses our very important sense , the common sense.) Now, Let's move to the other way.  The .concat( ); function have some similarities to "+" operator (NOTE: .concat() is not the same as "+"), aside from a fact that "+" can concat any variables compare to .concat( ) function who can concat only a string.  For example, (Explanations is on the comments!)

Introductory Topics before you start writing Java Codes

Different Data Types (most commonly use)

This short topic can give you an idea for different data types that is available to use on either the Java and C++.

a.) double num1 . . .  ;

     use to specify that the variable is a decimal point number. ex. 5.68 

b.) int num1 . . . ;

     use to specify that the variable is an integer. ex 7840 

c.) float num1 . . . ;

     same as double except that this type can handle bigger bits of decimal numbers. ex. 0.903994
d.) String word;
     use to specify that the word is a Character or a String.

Arithmetic Operators

Addition, Subtraction, Multiplication and Division.

Logical Operators

a.) Logical AND (&&)

shows that the two conditions must be satisfied in order to do a command.

Example:

The Console will ask for to enter grade then it will compute for the Grade. Later, It will decide whether the average is less than or equal to 100 and average is greater than or equal to 97.  If it is so, it will display the message "Your Great" otherwise "Better Luck next tym".

b.) Logical OR
shows that either one of the specified conditions must be meet in order to do a command.
Example:
if(x<90 || y=110){
. . . . . . . . . . . . . . . .. . . . ;
}
c.) Logical NOT
shows that if the conditional is not equal to a certain value a command will be executed.
Example:

Ternary Operators
-It uses the symbol (?).  It is a conditional that test if Exp1 is True, then Exp2 will be the value of the given expression.  If Exp1 is False, then Exp3 will be the value of the expression.
General Equation:
Exp1  ?  Exp2 : Exp3
Example

Then it will Output this one.

Incrementation and Decrementation
-It uses the symbol (++/--).  It is an operator that will add a certain value (usually 1).  It is the same as saying x = x +1.  Meaning the previous value of x will be added by 1 everytime it reach a certain condition.  So you must set a condition that will end up the adding process of the variable.
Example

In the created program, the console will keep the displaying the word "Enter grade:" until the counter reach the value of 3 (note that I initialize the value of the counter by 1).  The Program stated that WHILE the counter is less than or equal to 3 (meaning from 1 to 3), the program will keep on displaying the command "Enter Grade".  The Scanner will save the value you entered and do some operations. Finally, the program will display the output. The Console will display this one.