Java Tutorial

by Dinesh Thakur Category: Operators and Expressions

Most of the computer languages typically support advanced math operations (such as square root, trigonometric sine, cosine etc.) by way of function libraries. Java also provides a range of methods that support such functions in the standard libraries Math class stored in the package java.lang. Java's Math class contains a collection of methods and two constants that compute standard mathematical functions.



 
by Dinesh Thakur Category: Operators and Expressions

Arithmetic operators are used to perform arithmetic calculations. Java provides basic arithmetic operators. They are +,-, *, /, %. The different Arithmetic operators that were used in java programming.



 
by Dinesh Thakur Category: Operators and Expressions

Besides the assignment operator in Java has combined operators assignment. They contribute to reducing the amount of code as impracticable two operations by an operator. The combined operators have the following syntax:

 
by Dinesh Thakur Category: Operators and Expressions

Like the break statement, the continue statement also skips the remaining statements of the body of the loop where it is defined but instead of terminating the loop, the control is transferred to the beginning of the loop for next iteration. The loop continues until the test condition of the loop becomes false.

 
by Dinesh Thakur Category: Operators and Expressions

This Java continue statement with label example shows how to use java continue statement to skip to next iteration of the labeled loop.



 
by Dinesh Thakur Category: Operators and Expressions

Here is the Java Example for Area of Triangle

 
by Dinesh Thakur Category: Operators and Expressions

The break statement terminates the execution of the loop in which it is defined and the control is transferred immediately to the next executable statement after the loop. The break statement is normally used with either while, do-while, for or a switch statement. It is mostly used to exit early from the loop by skipping the remaining statements of loop or switch control structures.

 
by Dinesh Thakur Category: Operators and Expressions

In this example we reviewed six comparison operator <, <=,>,> =, == And ! =. Comparison operators always produce a boolean result value (true or false). Java has several comparison operator, which can be used for the comparison of any combination of integers, with float or symbols.

 
by Dinesh Thakur Category: Operators and Expressions

This Java break statement example shows how to use java break statement to terminate the loop. The Java break statement has two forms labeled and unlabeled. in the below example You can see unlabeled form.



 
by Dinesh Thakur Category: Control Structures

Different types of control statements: the decision making statements (if-then, if-then-else and switch), looping statements (while, do-while and for) and branching statements (break, continue and return).

 
by Dinesh Thakur Category: Control Structures

In Java, Jump statements are used to unconditionally transfer program control from one point to elsewhere in the program. Jump statements are primarily used to interrupt loop or switch-case instantly. Java supports three jump statements: break, continue, and return.

 
by Dinesh Thakur Category: Control Structures

Suppose, the value entered is say 121. It is assigned to an integer variable num. Now, num is divided by all the numbers from 2 to 8 (because a number can be divided by 1 and itself) (% rehrrns remainder). If the number is divided by any number from 2 to 8, its remainder will come to be 0 and in that case the message "Number is not prime" is displayed on the screen. 121 is not divisible by 2 but is no doubt divisible by 3 which returns remainder as 0 and hence it is not a prime number.

 
by Dinesh Thakur Category: Control Structures

If sum of factorial of each digit of the number is same as the actual number then that number is called as strong number.

 
by Dinesh Thakur Category: Control Structures

A Perfect Number is sum of its positive divisors, excluding the number itself. The First Perfect number is 6, For example 6 is a perfect number as 1,2 and3 are its divisors and the sum of divisors= ( 1 + 2 + 3)  = 6.

 
by Dinesh Thakur Category: Control Structures

final: Variables are useful when you need to store information that can change as the program runs. However, there may be certain situations in the program in which the value of the variable should not be allowed to modify. It is accomplished using a particular type of variable known as the final variable. The final variable also called constant variable. It is a variable with a value that cannot modify during the execution of the program.



 
by Dinesh Thakur Category: Control Structures

In this example, we input number of elements n (i.e.) whose average is to be calculated. When for loop begins executing, the loop control variable i is declared and initialized to 1. Then the test condition (i<=n) is checked. As it is true in this case because (1<=5) and the statements in the body of the loop are executed which inputs the first number (5 in our case) and add this value to variable sum. Then the increment expression i++ increases the value of variable i by 1 (i+ 1=2). After one complete iteration, the test condition in the for loop is checked again which is true again as (2<=5) and the body of the loop is executed again. This process continues until the loop control variable (i) is incremented to 6. Now when the test condition (6<=5) is evaluated again it becomes false and the execution of for loop terminates and control transfers to the next statement following the for loop that calculates the average of n (5) numbers which is then displayed.

 
by Dinesh Thakur Category: Control Structures

In this example, the sum of first 10 natural numbers is displayed. First, input the value of n (10 in this case) i.e. number of natural numbers whose sum is to be calculated. Then, after initializing the variables i to 1 and sum to 0, we enter the do-while loop. The execution of the body of loop continues as long as condition (i<=n) evaluates to true. When variable 1’s is value becomes 11, the condition becomes false and this terminates the do-while loop and program execution continues with the next statement after the loop which displays the sum of first 10 natural numbers.

 
by Dinesh Thakur Category: Control Structures

Algorithm for Check Number is Binary or Not:

step 1: Set r=0,c=0

step 2: Read num

step 3: Set b=num

step 4: Repeat through step-7 while num greater than 0

 
by Dinesh Thakur Category: Control Structures

Algorithm for Remove Vowels from a Sentence:

step 1: read String word

step 2: set char array c[]=word. to CharArray()

step 3: create new char array cc[] of size 80

 

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About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.