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Java Coding Practice

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In Java programming, commands are essential instructions that tell the computer what to do. These commands are written in a specific way so the computer can understand and execute them. Every program in Java is a set of commands. At the beginning of your Java programming practice , it’s good to know a few basic principles:

• In Java, each command ends with a semicolon;
• A command can't exist on its own: it’s a part of a method, and method is part of a class;
• Method (procedure, function) is a sequence of commands. Methods define the behavior of an object.

Here is an example of the command:

The command System.out.println("Hello, World!"); tells the computer to display the text inside the quotation marks.

If you want to display a number and not text, then you do not need to put quotation marks. You can simply write the number. Or an arithmetic operation. For example:

Command to display the number 1.

A command in which two numbers are summed and their sum (10) is displayed.

As we discussed in the basic rules, a command cannot exist on its own in Java. It must be within a method, and a method must be within a class. Here is the simplest program that prints the string "Hello, World!".

We have a class called HelloWorld , a method called main() , and the command System.out.println("Hello, World!") . You may not understand everything in the code yet, but that's okay! You'll learn more about it later. The good news is that you can already write your first program with the knowledge you've gained.

Attention! You can add comments in your code. Comments in Java are lines of code that are ignored by the compiler, but you can mark with them your code to make it clear for you and other programmers.

Single-line comments start with two forward slashes (//) and end at the end of the line. In example above we have a comment //here we print the text out

You can read the theory on this topic here , here , and here . But try practicing first!

Explore the Java coding exercises for practicing with commands below. First, read the conditions, scroll down to the Solution box, and type your solution. Then, click Verify (above the Conditions box) to check the correctness of your program.

The two main types in Java are String and int. We store strings/text in String, and integers (whole numbers) in int. We have already used strings and integers in previous examples without explicit declaration, by specifying them directly in the System.out.println() operator.

In the first case “I am a string” is a String in the second case 5 is an integer of type int. However, most often, in order to manipulate data, variables must be declared before being used in the program. To do this, you need to specify the type of the variable and its name. You can also set a variable to a specific value, or you can do this later. Example:

Here we declared a variable called a but didn't give it any value, declared a variable b and gave it the value 5 , declared a string called s and gave it the value Hello, World!

Attention! In Java, the = sign is not an equals sign, but an assignment operator. That is, the variable (you can imagine it as an empty box) is assigned the value that is on the right (you can imagine that this value was put in the empty box).

We created an integer variable named a with the first command and assigned it the value 5 with the second command.

Before moving on to practice, let's look at an example program where we will declare variables and assign values to them:

In the program, we first declared an int variable named a but did not immediately assign it a value. Then we declared an int variable named b and "put" the value 5 in it. Then we declared a string named s and assigned it the value "Hello, World!" After that, we assigned the value 2 to the variable a that we declared earlier, and then we printed the variable a, the sum of the variables a and b, and the variable s to the screen

This program will display the following:

We already know how to print to the console, but how do we read from it? For this, we use the Scanner class. To use Scanner, we first need to create an instance of the class. We can do this with the following code:

Once we have created an instance of Scanner, we can use the next() method to read input from the console or nextInt() if we should read an integer.

The following code reads a number from the console and prints it to the console:

Here we first import a library scanner, then ask a user to enter a number. Later we created a scanner to read the user's input and print the input out.

This code will print the following output in case of user’s input is 5:

More information about the topic you could read here , here , and here .

See the exercises on Types and keyboard input to practice Java coding:

Conditions and If statements in Java allow your program to make decisions. For example, you can use them to check if a user has entered a valid password, or to determine whether a number is even or odd. For this purpose, there’s an 'if/else statement' in Java.

The syntax for an if statement is as follows:

Here could be one or more conditions in if and zero or one condition in else.

Here's a simple example:

In this example, we check if the variable "age" is greater than or equal to 18. If it is, we print "You are an adult." If not, we print "You are a minor."

Here are some Java practice exercises to understand Conditions and If statements:

In Java, a "boolean" is a data type that can have one of two values: true or false. Here's a simple example:

The output of this program is here:

In addition to representing true or false values, booleans in Java can be combined using logical operators. Here, we introduce the logical AND (&&) and logical OR (||) operators.

• && (AND) returns true if both operands are true. In our example, isBothFunAndEasy is true because Java is fun (isJavaFun is true) and coding is not easy (isCodingEasy is false).
• || (OR) returns true if at least one operand is true. In our example, isEitherFunOrEasy is true because Java is fun (isJavaFun is true), even though coding is not easy (isCodingEasy is false).
• The NOT operator (!) is unary, meaning it operates on a single boolean value. It negates the value, so !isCodingEasy is true because it reverses the false value of isCodingEasy.

So the output of this program is:

More information about the topic you could read here , and here .

Here are some Java exercises to practice booleans:

With loops, you can execute any command or a block of commands multiple times. The construction of the while loop is:

Loops are essential in programming to execute a block of code repeatedly. Java provides two commonly used loops: while and for.

1. while Loop: The while loop continues executing a block of code as long as a specified condition is true. Firstly, the condition is checked. While it’s true, the body of the loop (commands) is executed. If the condition is always true, the loop will repeat infinitely, and if the condition is false, the commands in a loop will never be executed.

In this example, the code inside the while loop will run repeatedly as long as count is less than or equal to 5.

2. for Loop: The for loop is used for iterating a specific number of times.

In this for loop, we initialize i to 1, specify the condition i <= 5, and increment i by 1 in each iteration. It will print "Count: 1" to "Count: 5."

Here are some Java coding challenges to practice the loops:

An array in Java is a data structure that allows you to store multiple values of the same type under a single variable name. It acts as a container for elements that can be accessed using an index.

What you should know about arrays in Java:

• Indexing: Elements in an array are indexed, starting from 0. You can access elements by specifying their index in square brackets after the array name, like myArray[0] to access the first element.
• Initialization: To use an array, you must declare and initialize it. You specify the array's type and its length. For example, to create an integer array that can hold five values: int[] myArray = new int[5];
• Populating: After initialization, you can populate the array by assigning values to its elements. All elements should be of the same data type. For instance, myArray[0] = 10; myArray[1] = 20;.
• Default Values: Arrays are initialized with default values. For objects, this is null, and for primitive types (int, double, boolean, etc.), it's typically 0, 0.0, or false.

In this example, we create an integer array, assign values to its elements, and access an element using indexing.

In Java, methods are like mini-programs within your main program. They are used to perform specific tasks, making your code more organized and manageable. Methods take a set of instructions and encapsulate them under a single name for easy reuse. Here's how you declare a method:

• public is an access modifier that defines who can use the method. In this case, public means the method can be accessed from anywhere in your program.Read more about modifiers here .
• static means the method belongs to the class itself, rather than an instance of the class. It's used for the main method, allowing it to run without creating an object.
• void indicates that the method doesn't return any value. If it did, you would replace void with the data type of the returned value.

In this example, we have a main method (the entry point of the program) and a customMethod that we've defined. The main method calls customMethod, which prints a message. This illustrates how methods help organize and reuse code in Java, making it more efficient and readable.

In this example, we have a main method that calls the add method with two numbers (5 and 3). The add method calculates the sum and returns it. The result is then printed in the main method.

All composite types in Java consist of simpler ones, up until we end up with primitive types. An example of a primitive type is int, while String is a composite type that stores its data as a table of characters (primitive type char). Here are some examples of primitive types in Java:

• int: Used for storing whole numbers (integers). Example: int age = 25;
• double: Used for storing numbers with a decimal point. Example: double price = 19.99;
• char: Used for storing single characters. Example: char grade = 'A';
• boolean: Used for storing true or false values. Example: boolean isJavaFun = true;
• String: Used for storing text (a sequence of characters). Example: String greeting = "Hello, World!";

Simple types are grouped into composite types, that are called classes. Example:

We declared a composite type Person and stored the data in a String (name) and int variable for an age of a person. Since composite types include many primitive types, they take up more memory than variables of the primitive types.

See the exercises for a coding practice in Java data types:

String is the most popular class in Java programs. Its objects are stored in a memory in a special way. The structure of this class is rather simple: there’s a character array (char array) inside, that stores all the characters of the string.

String class also has many helper classes to simplify working with strings in Java, and a lot of methods. Here’s what you can do while working with strings: compare them, search for substrings, and create new substrings.

Example of comparing strings using the equals() method.

Also you can check if a string contains a substring using the contains() method.

You can create a new substring from an existing string using the substring() method.

More information about the topic you could read here , here , here , here , and here .

Here are some Java programming exercises to practice the strings:

In Java, objects are instances of classes that you can create to represent and work with real-world entities or concepts. Here's how you can create objects:

First, you need to define a class that describes the properties and behaviors of your object. You can then create an object of that class using the new keyword like this:

It invokes the constructor of a class.If the constructor takes arguments, you can pass them within the parentheses. For example, to create an object of class Person with the name "Jane" and age 25, you would write:

Suppose you want to create a simple Person class with a name property and a sayHello method. Here's how you do it:

In this example, we defined a Person class with a name property and a sayHello method. We then created two Person objects (person1 and person2) and used them to represent individuals with different names.

Here are some coding challenges in Java object creation:

Static classes and methods in Java are used to create members that belong to the class itself, rather than to instances of the class. They can be accessed without creating an object of the class.

Static methods and classes are useful when you want to define utility methods or encapsulate related classes within a larger class without requiring an instance of the outer class. They are often used in various Java libraries and frameworks for organizing and providing utility functions.

You declare them with the static modifier.

Static Methods

A static method is a method that belongs to the class rather than any specific instance. You can call a static method using the class name, without creating an object of that class.

In this example, the add method is static. You can directly call it using Calculator.add(5, 3)

Static Classes

In Java, you can also have static nested classes, which are classes defined within another class and marked as static. These static nested classes can be accessed using the outer class's name.

In this example, Student is a static nested class within the School class. You can access it using School.Student.

More information about the topic you could read here , here , here , and here .

See below the exercises on Static classes and methods in our Java coding practice for beginners:

• Java Course
• Java Arrays
• Java Strings
• Java Collection
• Java 8 Tutorial
• Java Multithreading
• Java Exception Handling
• Java Programs
• Java Project
• Java Collections Interview
• Java Interview Questions
• Spring Boot

Java Assignment Operators with Examples

Operators constitute the basic building block of any programming language. Java too provides many types of operators which can be used according to the need to perform various calculations and functions, be it logical, arithmetic, relational, etc. They are classified based on the functionality they provide.

Types of Operators: 

• Arithmetic Operators
• Unary Operators
• Assignment Operator
• Relational Operators
• Logical Operators
• Ternary Operator
• Bitwise Operators
• Shift Operators

This article explains all that one needs to know regarding Assignment Operators. 

Assignment Operators

These operators are used to assign values to a variable. The left side operand of the assignment operator is a variable, and the right side operand of the assignment operator is a value. The value on the right side must be of the same data type of the operand on the left side. Otherwise, the compiler will raise an error. This means that the assignment operators have right to left associativity, i.e., the value given on the right-hand side of the operator is assigned to the variable on the left. Therefore, the right-hand side value must be declared before using it or should be a constant. The general format of the assignment operator is, 

Types of Assignment Operators in Java

The Assignment Operator is generally of two types. They are:

1. Simple Assignment Operator: The Simple Assignment Operator is used with the “=” sign where the left side consists of the operand and the right side consists of a value. The value of the right side must be of the same data type that has been defined on the left side.

2. Compound Assignment Operator: The Compound Operator is used where +,-,*, and / is used along with the = operator.

Let’s look at each of the assignment operators and how they operate: 

1. (=) operator: 

This is the most straightforward assignment operator, which is used to assign the value on the right to the variable on the left. This is the basic definition of an assignment operator and how it functions. 

Syntax:  

Example:  

2. (+=) operator: 

This operator is a compound of ‘+’ and ‘=’ operators. It operates by adding the current value of the variable on the left to the value on the right and then assigning the result to the operand on the left. 

Note: The compound assignment operator in Java performs implicit type casting. Let’s consider a scenario where x is an int variable with a value of 5. int x = 5; If you want to add the double value 4.5 to the integer variable x and print its value, there are two methods to achieve this: Method 1: x = x + 4.5 Method 2: x += 4.5 As per the previous example, you might think both of them are equal. But in reality, Method 1 will throw a runtime error stating the “i ncompatible types: possible lossy conversion from double to int “, Method 2 will run without any error and prints 9 as output.

Reason for the Above Calculation

Method 1 will result in a runtime error stating “incompatible types: possible lossy conversion from double to int.” The reason is that the addition of an int and a double results in a double value. Assigning this double value back to the int variable x requires an explicit type casting because it may result in a loss of precision. Without the explicit cast, the compiler throws an error. Method 2 will run without any error and print the value 9 as output. The compound assignment operator += performs an implicit type conversion, also known as an automatic narrowing primitive conversion from double to int . It is equivalent to x = (int) (x + 4.5) , where the result of the addition is explicitly cast to an int . The fractional part of the double value is truncated, and the resulting int value is assigned back to x . It is advisable to use Method 2 ( x += 4.5 ) to avoid runtime errors and to obtain the desired output.

Same automatic narrowing primitive conversion is applicable for other compound assignment operators as well, including -= , *= , /= , and %= .

3. (-=) operator: 

This operator is a compound of ‘-‘ and ‘=’ operators. It operates by subtracting the variable’s value on the right from the current value of the variable on the left and then assigning the result to the operand on the left. 

4. (*=) operator:

 This operator is a compound of ‘*’ and ‘=’ operators. It operates by multiplying the current value of the variable on the left to the value on the right and then assigning the result to the operand on the left. 

5. (/=) operator: 

This operator is a compound of ‘/’ and ‘=’ operators. It operates by dividing the current value of the variable on the left by the value on the right and then assigning the quotient to the operand on the left. 

6. (%=) operator: 

This operator is a compound of ‘%’ and ‘=’ operators. It operates by dividing the current value of the variable on the left by the value on the right and then assigning the remainder to the operand on the left. 

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Java Basic Programming : Exercises, Practice, Solution

Java basic exercises [150 exercises with solution].

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1. Write a Java program to print 'Hello' on screen and your name on a separate line. Expected Output : Hello Alexandra Abramov

Click me to see the solution

2. Write a Java program to print the sum of two numbers. Test Data: 74 + 36 Expected Output : 110

3. Write a Java program to divide two numbers and print them on the screen. Test Data : 50/3 Expected Output : 16

4. Write a Java program to print the results of the following operations. Test Data: a. -5 + 8 * 6 b. (55+9) % 9 c. 20 + -3*5 / 8 d. 5 + 15 / 3 * 2 - 8 % 3 Expected Output : 43 1 19 13

5. Write a Java program that takes two numbers as input and displays the product of two numbers. Test Data: Input first number: 25 Input second number: 5 Expected Output : 25 x 5 = 125

6. Write a Java program to print the sum (addition), multiply, subtract, divide and remainder of two numbers. Test Data: Input first number: 125 Input second number: 24 Expected Output : 125 + 24 = 149 125 - 24 = 101 125 x 24 = 3000 125 / 24 = 5 125 mod 24 = 5

7. Write a Java program that takes a number as input and prints its multiplication table up to 10. Test Data: Input a number: 8 Expected Output : 8 x 1 = 8 8 x 2 = 16 8 x 3 = 24 ... 8 x 10 = 80

8. Write a Java program to display the following pattern. Sample Pattern :

9. Write a Java program to compute the specified expressions and print the output. Test Data: ((25.5 * 3.5 - 3.5 * 3.5) / (40.5 - 4.5)) Expected Output 2.138888888888889

10. Write a Java program to compute a specified formula. Specified Formula : 4.0 * (1 - (1.0/3) + (1.0/5) - (1.0/7) + (1.0/9) - (1.0/11)) Expected Output 2.9760461760461765

11. Write a Java program to print the area and perimeter of a circle. Test Data: Radius = 7.5 Expected Output Perimeter is = 47.12388980384689 Area is = 176.71458676442586

12. Write a Java program that takes three numbers as input to calculate and print the average of the numbers. Click me to see the solution

13. Write a Java program to print the area and perimeter of a rectangle. Test Data: Width = 5.5 Height = 8.5

Expected Output Area is 5.6 * 8.5 = 47.60 Perimeter is 2 * (5.6 + 8.5) = 28.20

14. Write a Java program to print an American flag on the screen. Expected Output

15. Write a Java program to swap two variables. Click me to see the solution

16. Write a Java program to print a face. Expected Output

17. Write a Java program to add two binary numbers. Input Data: Input first binary number: 10 Input second binary number: 11 Expected Output

18. Write a Java program to multiply two binary numbers. Input Data: Input the first binary number: 10 Input the second binary number: 11 Expected Output

19. Write a Java program to convert an integer number to a binary number. Input Data: Input a Decimal Number : 5 Expected Output

20. Write a Java program to convert a decimal number to a hexadecimal number. Input Data: Input a decimal number: 15 Expected Output

21. Write a Java program to convert a decimal number to an octal number. Input Data: Input a Decimal Number: 15 Expected Output

22. Write a Java program to convert a binary number to a decimal number. Input Data: Input a binary number: 100 Expected Output

23. Write a Java program to convert a binary number to a hexadecimal number. Input Data: Input a Binary Number: 1101 Expected Output

24. Write a Java program to convert a binary number to an octal number. Input Data: Input a Binary Number: 111 Expected Output

25. Write a Java program to convert a octal number to a decimal number. Input Data: Input any octal number: 10 Expected Output

26. Write a Java program to convert a octal number to a binary number. Input Data: Input any octal number: 7 Expected Output

27. Write a Java program to convert a octal number to a hexadecimal number. Input Data: Input a octal number : 100 Expected Output

28. Write a Java program to convert a hexadecimal value into a decimal number. Input Data: Input a hexadecimal number: 25 Expected Output

29. Write a Java program to convert a hexadecimal number into a binary number. Input Data: Enter Hexadecimal Number : 37 Expected Output

30. Write a Java program to convert a hexadecimal value into an octal number. Input Data: Input a hexadecimal number: 40 Expected Output

31. Write a Java program to check whether Java is installed on your computer. Expected Output

32. Write a Java program to compare two numbers. Input Data: Input first integer: 25 Input second integer: 39 Expected Output

33. Write a Java program and compute the sum of an integer's digits. Input Data: Input an integer: 25 Expected Output

34. Write a Java program to compute hexagon area. Area of a hexagon = (6 * s^2)/(4*tan(π/6)) where s is the length of a side Input Data: Input the length of a side of the hexagon: 6 Expected Output

35. Write a Java program to compute the area of a polygon. Area of a polygon = (n*s^2)/(4*tan(π/n)) where n is n-sided polygon and s is the length of a side Input Data: Input the number of sides on the polygon: 7 Input the length of one of the sides: 6 Expected Output

36. Write a Java program to compute the distance between two points on the earth's surface. Distance between the two points [ (x1,y1) & (x2,y2)] d = radius * arccos(sin(x1) * sin(x2) + cos(x1) * cos(x2) * cos(y1 - y2)) Radius of the earth r = 6371.01 Kilometers Input Data: Input the latitude of coordinate 1: 25 Input the longitude of coordinate 1: 35 Input the latitude of coordinate 2: 35.5 Input the longitude of coordinate 2: 25.5 Expected Output

37. Write a Java program to reverse a string. Input Data: Input a string: The quick brown fox Expected Output

38. Write a Java program to count letters, spaces, numbers and other characters in an input string. Expected Output

39. Write a Java program to create and display a unique three-digit number using 1, 2, 3, 4. Also count how many three-digit numbers are there. Expected Output

40. Write a Java program to list the available character sets in charset objects. Expected Output

41. Write a Java program to print the ASCII value of a given character. Expected Output

42. Write a Java program to input and display your password. Expected Output

43. Write a Java program to print the following string in a specific format (see output). Sample Output

44. Write a Java program that accepts an integer (n) and computes the value of n+nn+nnn. Sample Output:

45. Write a Java program to find the size of a specified file. Sample Output:

46. Write a Java program to display system time. Sample Output:

47. Write a Java program to display the current date and time in a specific format. Sample Output:

48. Write a Java program to print odd numbers from 1 to 99. Prints one number per line. Sample Output:

49. Write a Java program to accept a number and check whether the number is even or not. Prints 1 if the number is even or 0 if odd. Sample Output:

50. Write a Java program to print numbers between 1 and 100 divisible by 3, 5 and both. Sample Output:

51. Write a Java program to convert a string to an integer. Sample Output:

52. Write a Java program to calculate the sum of two integers and return true if the sum is equal to a third integer. Sample Output:

53. Write a Java program that accepts three integers from the user. It returns true if the second number is higher than the first number and the third number is larger than the second number. If "abc" is true, the second number does not need to be larger than the first number. Sample Output:

54. Write a Java program that accepts three integers from the user and returns true if two or more of them (integers) have the same rightmost digit. The integers are non-negative. Sample Output:

55. Write a Java program to convert seconds to hours, minutes and seconds. Sample Output:

56. Write a Java program to find the number of values in a given range divisible by a given value. For example x = 5, y=20 and p =3, find the number of integers within the range x..y and that are divisible by p i.e. { i :x ≤ i ≤ y, i mod p = 0 } Sample Output:

57. Write a Java program to accept an integer and count the factors of the number. Sample Output:

58. Write a Java program to capitalize the first letter of each word in a sentence. Sample Output:

59. Write a Java program to convert a string into lowercase. Sample Output:

60. Write a Java program to find the penultimate (next to the last) word in a sentence. Sample Output:

61. Write a Java program to reverse a word. Sample Output:

62. Write a Java program that accepts three integer values and returns true if one is 20 or more less than the others' subtractions. Sample Output:

63. Write a Java program that accepts two integer values from the user and returns the largest value. However if the two values are the same, return 0 and find the smallest value if the two values have the same remainder when divided by 6. Sample Output:

64. Write a Java program that accepts two integer values between 25 and 75 and returns true if there is a common digit in both numbers. Sample Output:

65. Write a Java program to calculate the modules of two numbers without using any inbuilt modulus operator. Sample Output:

66. Write a Java program to compute the sum of the first 100 prime numbers. Sample Output:

67. Write a Java program to insert a word in the middle of another string. Insert "Tutorial" in the middle of "Python 3.0", so the result will be Python Tutorial 3.0. Sample Output:

68. Write a Java program to create another string of 4 copies of the last 3 characters of the original string. The original string length must be 3 and above. Sample Output:

70. Write a Java program to create a string in the form of short_string + long_string + short_string from two strings. The strings must not have the same length. Test Data: Str1 = Python Str2 = Tutorial Sample Output:

71. Write a Java program to create the concatenation of the two strings except removing the first character of each string. The length of the strings must be 1 and above. Test Data: Str1 = Python Str2 = Tutorial Sample Output:

72. Write a Java program to create a string taking the first three characters from a given string. If the string length is less than 3 use "#" as substitute characters. Test Data: Str1 = " " Sample Output:

73. Write a Java program to create a string taking the first and last characters from two given strings. If the length of each string is 0 use "#" for missing characters. Test Data: str1 = "Python" str2 = " " Sample Output:

74. Write a Java program to test if 10 appears as the first or last element of an array of integers. The array length must be broader than or equal to 2. Sample Output: Test Data: array = 10, -20, 0, 30, 40, 60, 10

75. Write a Java program to test if the first and last elements of an array of integers are the same. The array length must be broader than or equal to 2. Test Data: array = 50, -20, 0, 30, 40, 60, 10 Sample Output:

76. Write a Java program to test if the first and last element of two integer arrays are the same. The array length must be greater than or equal to 2. Test Data: array1 = 50, -20, 0, 30, 40, 60, 12 array2 = 45, 20, 10, 20, 30, 50, 11 Sample Output:

77. Write a Java program to create an array of length 2 from two integer arrays with three elements. The newly created array will contain the first and last elements from the two arrays. Test Data: array1 = 50, -20, 0 array2 = 5, -50, 10 Sample Output:

78. Write a Java program to test that a given array of integers of length 2 contains a 4 or a 7. Sample Output:

79. Write a Java program to rotate an array (length 3) of integers in the left direction. Sample Output:

80. Write a Java program to get the largest value between the first and last elements of an array (length 3) of integers. Sample Output:

81. Write a Java program to swap the first and last elements of an array (length must be at least 1) and create another array. Sample Output:

82. Write a Java program to find the largest element between the first, last, and middle values in an array of integers (even length). Sample Output:

83. Write a Java program to multiply the corresponding elements of two integer arrays. Sample Output:

84. Write a Java program to take the last three characters from a given string. It will add the three characters at both the front and back of the string. String length must be greater than three and more. Test data: "Python" will be "honPythonhon" Sample Output:

85. Write a Java program to check if a string starts with a specified word. Sample Data: string1 = "Hello how are you?" Sample Output:

88. Write a Java program to get the current system environment and system properties. Click me to see the solution

89. Write a Java program to check whether a security manager has already been established for the current application or not. Click me to see the solution

90. Write a Java program to get the value of environment variables PATH, TEMP, USERNAME. Click me to see the solution

91. Write a Java program to measure how long code executes in nanoseconds. Click me to see the solution

92. Write a Java program to count the number of even and odd elements in a given array of integers. Click me to see the solution

93. Write a Java program to test if an array of integers contains an element 10 next to 10 or an element 20 next to 20, but not both. Click me to see the solution

94. Write a Java program to rearrange all the elements of a given array of integers so that all the odd numbers come before all the even numbers. Click me to see the solution

95. Write a Java program to create an array (length # 0) of string values. The elements will contain "0", "1", "2" … through ... n-1. Click me to see the solution

96. Write a Java program to check if there is a 10 in an array of integers with a 20 somewhere later on. Click me to see the solution

97. Write a Java program to check if an array of integers contains a specified number next to each other or two same numbers separated by one element. Click me to see the solution

98. Write a Java program to check if the value 20 appears three times and no 20's are next to each other in the array of integers. Click me to see the solution

99. Write a Java program that checks if a specified number appears in every pair of adjacent integers of a given array of integers. Click me to see the solution

100. Write a Java program to count the elements that differ by 1 or less between two given arrays of integers with the same length. Click me to see the solution

101. Write a Java program to determine whether the number 10 in a given array of integers exceeds 20. Click me to see the solution

102. Write a Java program to check if a specified array of integers contains 10 or 30. Click me to see the solution

103. Write a Java program to create an array from a given array of integers. The newly created array will contain elements from the given array after the last element value is 10. Click me to see the solution

104. Write a Java program to create an array from a given array of integers. The newly created array will contain the elements from the given array before the last element value of 10. Click me to see the solution

105. Write a Java program to check if a group of numbers (l) at the start and end of a given array are the same. Click me to see the solution

106. Write a Java program to create an array left shifted from a given array of integers. Click me to see the solution

107. Write a Java program to check if an array of integers contains three increasing adjacent numbers. Click me to see the solution

108. Write a Java program to add all the digits of a given positive integer until the result has a single digit. Click me to see the solution

109. Write a Java program to form a staircase shape of n coins where every k-th row must have exactly k coins. Click me to see the solution

110. Write a Java program to check whether the given integer is a power of 4 or not. Given num = 64, return true. Given num = 6, return false. Click me to see the solution

111. Write a Java program to add two numbers without arithmetic operators. Given x = 10 and y = 12; result = 22 Click me to see the solution

112. Write a Java program to compute the number of trailing zeros in a factorial. 7! = 5040, therefore the output should be 1 Click me to see the solution

113. Write a Java program to merge two given sorted arrays of integers and create another sorted array. array1 = [1,2,3,4] array2 = [2,5,7, 8] result = [1,2,2,3,4,5,7,8] Click me to see the solution

114. Write a Java program that rotates a string by an offset (rotate from left to right. Click me to see the solution

115. Write a Java program to check if a positive number is a palindrome or not. Input a positive integer: 151 Is 151 is a palindrome number? true Click me to see the solution

116. Write a Java program that iterates integers from 1 to 100. For multiples of three print "Fizz" instead of the number and print "Buzz" for five. When the number is divided by three and five, print "fizz buzz". Click me to see the solution

117. Write a Java program to compute the square root of a given number. Input a positive integer: 25 Square root of 25 is: 5 Click me to see the solution

118. Write a Java program to get the first occurrence (Position starts from 0.) of a string within a given string. Click me to see the solution

119. Write a Java program to get the first occurrence (Position starts from 0.) of an element of a given array. Click me to see the solution

120. Write a Java program that searches for a value in an m x n matrix. Click me to see the solution

121. Write a Java program to reverse a linked list. Example: For linked list 20->40->60->80, the reversed linked list is 80->60->40->20 Click me to see the solution

122. Write a Java program to find a contiguous subarray with the largest sum from a given array of integers. Note: In computer science, the maximum subarray problem is the task of finding the contiguous subarray within a one-dimensional array of numbers which has the largest sum. For example, for the sequence of values −2, 1, −3, 4, −1, 2, 1, −5, 4; the contiguous subarray with the largest sum is 4, −1, 2, 1, with sum 6. The subarray should contain one integer at least. Click me to see the solution

123. Write a Java program to find the subarray with smallest sum from a given array of integers. Click me to see the solution

124. Write a Java program to find the index of a value in a sorted array. If the value does not find return the index where it would be if it were inserted in order. Example: [1, 2, 4, 5, 6] 5(target) -> 3(index) [1, 2, 4, 5, 6] 0(target) -> 0(index) [1, 2, 4, 5, 6] 7(target) -> 5(index) Click me to see the solution

125. Write a Java program to get the preorder traversal of the values of the nodes in a binary tree. Example: 10 / \ 20 30 / \ 40 50 Expected output: 10 20 40 50 30 Click me to see the solution

126. Write a Java program to get the in-order traversal of its nodes' values in a binary tree. 10 / \ 20 30 / \ 40 50 Example:{10, 20, 30, 40, 50} Output: 40 20 50 10 30 Click me to see the solution

127. Write a Java program to get the Postorder traversal of its nodes' values in a binary tree. 10 / \ 20 30 / \ 40 50 Click me to see the solution

128. Write a Java program to calculate the median of a non-sorted array of integers. Original array: [10, 2, 38, 22, 38, 23] Median of the said array of integers: 30 Original array: [10, 2, 38, 23, 38, 23, 21] Median of the said array of integers: 23 Click me to see the solution

129. Write a Java program to find a number that appears only once in a given array of integers. All numbers occur twice. Source Array : [10, 20, 10, 20, 30, 40, 40, 30, 50] 50 appears only once Click me to see the solution

130. Write a Java program to find the maximum depth of a given binary tree. Sample Output: The Maximum depth of the binary tree is: 3 Click me to see the solution

131. Write a Java program to find the updated length of a sorted array where each element appears only once (remove duplicates). Original array: [1, 1, 2, 3, 3, 3, 4, 5, 6, 7, 7] The length of the original array is: 11 After removing duplicates, the new length of the array is: 7 Click me to see the solution

132. Write a Java program to find the updated length of a given sorted array where duplicate elements appear at most twice. Original array: [1, 1, 2, 3, 3, 3, 4, 5, 6, 7, 7, 7, 7] The length of the original array is: 13 After removing duplicates, the new length of the array is: 10 Click me to see the solution

133. Write a Java program to find a path from top left to bottom in the right direction which minimizes the sum of all numbers along its path. Note: Move either down or right at any point in time. Sample Output: Sum of all numbers along its path: 13 Click me to see the solution

134. Write a Java program to find distinct ways to climb to the top (n steps to reach the top) of stairs. Each time you climb, you can climb 1 or 2 steps. Example: n = 5 a) 1+1+1+1+1 = 5 b) 1+1+1+2 = 5 c) 1+2+2 = 5 d) 2+2+1 = 5 e) 2+1+1+1 = 5 f) 2+1+2 = 5 g) 1+2+1+1 = 5 h) 1+1+2+1 = 5 Sample Output: Distinct ways can you climb to the top: 8 Click me to see the solution

135. Write a Java program to remove duplicates from a sorted linked list. Original List with duplicate elements: 12->12->13->14->15->15->16->17->17 After removing duplicates from the said list: 12->13->14->15->16->17 Click me to see the solution

136. Write a Java program to find possible distinct paths from the top-left corner to the bottom-right corner of a given grid (m x n). Note: You can move either down or right at any point in time. Sample Output: Unique paths from top-left corner to bottom-right corner of the said grid: 3 Click me to see the solution

137. Write a Java program to find possible unique paths considering some obstacles, from top-left corner to bottom-right corner of a given grid (m x n). Note: You can move either down or right at any point in time and an obstacle and empty space is marked as 1 and 0 respectively in the grid. Sample grid: int[][] obstacle_Grid ={ {0, 0, 0}, {0, 1, 0}, {0, 0, 0}, }; Sample Output: Unique paths from top-left corner to bottom-right corner of the said grid (considering some obstacles): 2 Click me to see the solution

138. Write a Java program to find the longest words in a dictionary. Example-1: { "cat", "flag", "green", "country", "w3resource" } Result: "w3resource" Example-2: { "cat", "dog", "red", "is", "am" } Result: "cat", "dog", "red" Click me to see the solution

139. Write a Java program to get the index of the first and the last number of a subarray where the sum of numbers is zero. This is from a given array of integers. Original Array : [1, 2, 3, -6, 5, 4] Index of the subarray of the said array where the sum of numbers is zero: [0, 3] Click me to see the solution

140. Write a Java program to merge all overlapping intervals from a given collection of intervals. Sample Output: 1 6 8 10 15 20 Click me to see the solution

141. Write a Java program to check if a given string has all distinct characters. Sample Output: Original String : xyyz String has all unique characters: false Click me to see the solution

142. Write a Java program to check if two strings are anagrams or not. According to Wikipedia "An anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once. For example, the word anagram can be rearranged into nag a ram, or the word binary into brainy." Sample Output: String-1 : wxyz String-2 : zyxw Check if two given strings are anagrams or not?: true Click me to see the solution

143. Write a Java program to merge the two sorted linked lists. Sample Output: Merge Two Sorted ListsT: 1 2 3 7 9 13 40 Click me to see the solution

144. Write a Java program to remove all occurrences of a specified value in a given array of integers. Return the updated array length. Sample Output: Original array: [1, 4, 6, 7, 6, 2] The length of the new array is: 4 Click me to see the solution

145. Write a Java program to remove the nth element from the end of a given list. Sample Output: Original node: 1 2 3 4 5 After removing 2nd element from end: 1 2 3 5 Click me to see the solution

146. Write a Java program to convert an array of sorted items into a binary search tree. Maintain the minimal height of the tree. Sample Output: 2 1 4 6 5 3 Click me to see the solution

147. Write a Java program to find the number of bits required to flip to convert two given integers. Sample Output: 2 Click me to see the solution

148. Write a Java program to find the index of the first unique character in a given string. Assume that there is at least one unique character in the string. Sample Output: Original String: wresource First unique character of the above: 0 Click me to see the solution

149. Write a Java program to check if a given string is a permutation of another given string. Sample Output: Original strings: xxyz yxzx true Click me to see the solution

150. Write a Java program to test if a binary tree is a subtree of another binary tree. Sample Output: Original strings: xxyz yxzx true Click me to see the solution

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Assignment, Arithmetic, and Unary Operators

The simple assignment operator.

One of the most common operators that you'll encounter is the simple assignment operator " = ". You saw this operator in the Bicycle class; it assigns the value on its right to the operand on its left:

This operator can also be used on objects to assign object references , as discussed in Creating Objects .

The Arithmetic Operators

The Java programming language provides operators that perform addition, subtraction, multiplication, and division. There's a good chance you'll recognize them by their counterparts in basic mathematics. The only symbol that might look new to you is " % ", which divides one operand by another and returns the remainder as its result.

The following program, ArithmeticDemo , tests the arithmetic operators.

This program prints the following:

You can also combine the arithmetic operators with the simple assignment operator to create compound assignments . For example, x+=1; and x=x+1; both increment the value of x by 1.

The + operator can also be used for concatenating (joining) two strings together, as shown in the following ConcatDemo program:

By the end of this program, the variable thirdString contains "This is a concatenated string.", which gets printed to standard output.

The Unary Operators

The unary operators require only one operand; they perform various operations such as incrementing/decrementing a value by one, negating an expression, or inverting the value of a boolean.

The following program, UnaryDemo , tests the unary operators:

The increment/decrement operators can be applied before (prefix) or after (postfix) the operand. The code result++; and ++result; will both end in result being incremented by one. The only difference is that the prefix version ( ++result ) evaluates to the incremented value, whereas the postfix version ( result++ ) evaluates to the original value. If you are just performing a simple increment/decrement, it doesn't really matter which version you choose. But if you use this operator in part of a larger expression, the one that you choose may make a significant difference.

The following program, PrePostDemo , illustrates the prefix/postfix unary increment operator:

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Java Assignment Operators

Java programming tutorial index.

The Java Assignment Operators are used when you want to assign a value to the expression. The assignment operator denoted by the single equal sign = .

In a Java assignment statement, any expression can be on the right side and the left side must be a variable name. For example, this does not mean that "a" is equal to "b", instead, it means assigning the value of 'b' to 'a'. It is as follows:

Java also has the facility of chain assignment operators, where we can specify a single value for multiple variables.

Java Assignment Operators

Java Assignment Operators example

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Operators are symbols that perform operations on variables and values. For example, + is an operator used for addition, while * is also an operator used for multiplication.

Operators in Java can be classified into 5 types:

• Arithmetic Operators
• Assignment Operators
• Relational Operators
• Logical Operators
• Unary Operators
• Bitwise Operators

1. Java Arithmetic Operators

Arithmetic operators are used to perform arithmetic operations on variables and data. For example,

Here, the + operator is used to add two variables a and b . Similarly, there are various other arithmetic operators in Java.

Example 1: Arithmetic Operators

In the above example, we have used + , - , and * operators to compute addition, subtraction, and multiplication operations.

/ Division Operator

Note the operation, a / b in our program. The / operator is the division operator.

If we use the division operator with two integers, then the resulting quotient will also be an integer. And, if one of the operands is a floating-point number, we will get the result will also be in floating-point.

% Modulo Operator

The modulo operator % computes the remainder. When a = 7 is divided by b = 4 , the remainder is 3 .

Note : The % operator is mainly used with integers.

2. Java Assignment Operators

Assignment operators are used in Java to assign values to variables. For example,

Here, = is the assignment operator. It assigns the value on its right to the variable on its left. That is, 5 is assigned to the variable age .

Let's see some more assignment operators available in Java.

Example 2: Assignment Operators

3. java relational operators.

Relational operators are used to check the relationship between two operands. For example,

Here, < operator is the relational operator. It checks if a is less than b or not.

It returns either true or false .

Example 3: Relational Operators

Note : Relational operators are used in decision making and loops.

4. Java Logical Operators

Logical operators are used to check whether an expression is true or false . They are used in decision making.

Example 4: Logical Operators

Working of Program

• (5 > 3) && (8 > 5) returns true because both (5 > 3) and (8 > 5) are true .
• (5 > 3) && (8 < 5) returns false because the expression (8 < 5) is false .
• (5 < 3) || (8 > 5) returns true because the expression (8 > 5) is true .
• (5 > 3) || (8 < 5) returns true because the expression (5 > 3) is true .
• (5 < 3) || (8 < 5) returns false because both (5 < 3) and (8 < 5) are false .
• !(5 == 3) returns true because 5 == 3 is false .
• !(5 > 3) returns false because 5 > 3 is true .

5. Java Unary Operators

Unary operators are used with only one operand. For example, ++ is a unary operator that increases the value of a variable by 1 . That is, ++5 will return 6 .

Different types of unary operators are:

• Increment and Decrement Operators

Java also provides increment and decrement operators: ++ and -- respectively. ++ increases the value of the operand by 1 , while -- decrease it by 1 . For example,

Here, the value of num gets increased to 6 from its initial value of 5 .

Example 5: Increment and Decrement Operators

In the above program, we have used the ++ and -- operator as prefixes (++a, --b) . We can also use these operators as postfix (a++, b++) .

There is a slight difference when these operators are used as prefix versus when they are used as a postfix.

To learn more about these operators, visit increment and decrement operators .

6. Java Bitwise Operators

Bitwise operators in Java are used to perform operations on individual bits. For example,

Here, ~ is a bitwise operator. It inverts the value of each bit ( 0 to 1 and 1 to 0 ).

The various bitwise operators present in Java are:

These operators are not generally used in Java. To learn more, visit Java Bitwise and Bit Shift Operators .

Other operators

Besides these operators, there are other additional operators in Java.

The instanceof operator checks whether an object is an instanceof a particular class. For example,

Here, str is an instance of the String class. Hence, the instanceof operator returns true . To learn more, visit Java instanceof .

The ternary operator (conditional operator) is shorthand for the if-then-else statement. For example,

Here's how it works.

• If the Expression is true , expression1 is assigned to the variable .
• If the Expression is false , expression2 is assigned to the variable .

Let's see an example of a ternary operator.

In the above example, we have used the ternary operator to check if the year is a leap year or not. To learn more, visit the Java ternary operator .

Now that you know about Java operators, it's time to know about the order in which operators are evaluated. To learn more, visit Java Operator Precedence .

Table of Contents

• Introduction
• Java Arithmetic Operators
• Java Assignment Operators
• Java Relational Operators
• Java Logical Operators
• Java Unary Operators
• Java Bitwise Operators

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Operators are used to perform operations on variables and values.

In the example below, we use the + operator to add together two values:

Try it Yourself »

Although the + operator is often used to add together two values, like in the example above, it can also be used to add together a variable and a value, or a variable and another variable:

Java divides the operators into the following groups:

• Arithmetic operators
• Assignment operators
• Comparison operators
• Logical operators
• Bitwise operators

Arithmetic Operators

Arithmetic operators are used to perform common mathematical operations.

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Java Assignment Operators

Assignment operators are used to assign values to variables.

In the example below, we use the assignment operator ( = ) to assign the value 10 to a variable called x :

The addition assignment operator ( += ) adds a value to a variable:

A list of all assignment operators:

Java Comparison Operators

Comparison operators are used to compare two values (or variables). This is important in programming, because it helps us to find answers and make decisions.

The return value of a comparison is either true or false . These values are known as Boolean values , and you will learn more about them in the Booleans and If..Else chapter.

In the following example, we use the greater than operator ( > ) to find out if 5 is greater than 3:

Java Logical Operators

You can also test for true or false values with logical operators.

Logical operators are used to determine the logic between variables or values:

Java Bitwise Operators

Bitwise operators are used to perform binary logic with the bits of an integer or long integer.

Note: The Bitwise examples above use 4-bit unsigned examples, but Java uses 32-bit signed integers and 64-bit signed long integers. Because of this, in Java, ~5 will not return 10. It will return -6. ~00000000000000000000000000000101 will return 11111111111111111111111111111010

In Java, 9 >> 1 will not return 12. It will return 4. 00000000000000000000000000001001 >> 1 will return 00000000000000000000000000000100

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Multiply 10 with 5 , and print the result.

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• Java Operators

Last updated: January 8, 2024

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1. Overview

Operators are a fundamental building block of any programming language. We use operators to perform operations on values and variables.

Java provides many groups of operators. They are categorized by their functionalities.

In this tutorial, we’ll walk through all Java operators to understand their functionalities and how to use them.

2. Arithmetic Operators

We use arithmetic operators to perform simple mathematical operations. We should note that arithmetic operators only work with primitive number types and their boxed types , such as int and  Integer .

Next, let’s see what operators we have in the arithmetic operator group.

2.1. The Addition Operator

The addition operator (+) allows us to add two values or concatenate two strings:

2.2. The Subtraction Operator

Usually, we use the subtraction operator (-) to subtract one value from another:

2.3. The Multiplication Operator

The multiplication operator (*) is used to multiply two values or variables:

2.4. The Division Operator

The division operator (/) allows us to divide the left-hand value by the right-hand one:

When we use the division operator on two integer values ( byte , short , int , and long ), we should note that the result is the quotient value. The remainder is not included .

As the example above shows, if we calculate 15 / 2 , the quotient is 7, and the remainder is 1 . Therefore, we have 15 / 2 = 7 .

2.5. The Modulo Operator

We can get the quotient using the division operator. However, if we just want to get the remainder of a division calculation, we can use the modulo operator (%):

3. Unary Operators

As the name implies, unary operators only require one single operand . For example, we usually use unary operators to increment, decrement, or negate a variable or value.

Now, let’s see the details of unary operators in Java.

3.1. The Unary Plus Operator

The unary plus operator (+) indicates a positive value. If the number is positive, we can omit the ‘+’ operator:

3.2. The Unary Minus Operator

Opposite to the unary plus operator, the unary minus operator (-) negates a value or an expression:

3.3. The Logical Complement Operator

The logical complement operator (!) is also known as the “NOT” operator . We can use it to invert the value of a boolean variable or value:

3.4. The Increment Operator

The increment operator (++) allows us to increase the value of a variable by 1:

3.5. The Decrement Opeartor

The decrement operator (–) does the opposite of the increment operator. It decreases the value of a variable by 1:

We should keep in mind that the increment and decrement operators can only be used on a variable . For example, “ int a = 5; a++; ” is fine. However, the expression “ 5++ ” won’t be compiled.

4. Relational Operators

Relational operators can be called “comparison operators” as well. Basically, we use these operators to compare two values or variables.

4.1. The “Equal To” Operator

We use the “equal to” operator (==) to compare the values on both sides. If they’re equal, the operation returns true :

The “equal to” operator is pretty straightforward. On the other hand, the Object class has provided the equals() method. As the Object class is the superclass of all Java classes, all Java objects can use the equals() method to compare each other.

When we want to compare two objects – for instance, when we compare Long objects or compare String s –  we should choose between the comparison method from the equals() method and that of the “equal to” operator wisely .

4.2. The “Not Equal To” Operator

The “not equal to” operator (!=) does the opposite of the ‘==’ operator. If the values on both sides are not equal, the operation returns true :

4.3. The “Greater Than” Operator

When we compare two values with the “greater than” operator (>), it returns true if the value on the left-hand side is greater than the value on the right-hand side:

4.4. The “Greater Than or Equal To” Operator

The “greater than or equal to” operator (>=) compares the values on both sides and returns true if the left-hand side operand is greater than or equal to the right-hand side operand:

4.5. The “Less Than” Operator

The “less than” operator (<) compares two values on both sides and returns true if the value on the left-hand side is less than the value on the right-hand side:

4.6. The “Less Than or Equal To” Operator

Similarly, the “less than or equal to” operator (<=) compares the values on both sides and returns true if the left-hand side operand is less than or equal to the right-hand side:

5. Logical Operators

We have two logical operators in Java: the logical AND and OR operators. Basically, their function is pretty similar to the AND gate and the OR gate in digital electronics.

Usually, we use a logical operator with two operands, which are variables or expressions that can be evaluated as boolean .

Next, let’s take a closer look at them.

5.1. The Logical AND Operator

The logical AND operator ( && ) returns true only if both operands are true :

5.2. The Logical OR Operator

Unlike the ‘ && ‘ operator, the logical OR operator ( || ) returns true if at least one operand is  true :

We should note that the logical OR operator has the short-circuiting effect : It returns true as soon as one of the operands is evaluated as true, without evaluating the remaining operands.

6. Ternary Operator

A ternary operator is a short form of the if-then-else statement. It has the name ternary as it has three operands. First, let’s have a look at the standard if-then-else statement syntax:

We can convert the above if-then-else statement into a compact version using the ternary operator:

Let’s look at its syntax:

Next, let’s understand how the ternary operator works through a simple example:

7. Bitwise and Bit Shift Operators

As the article “ Java bitwise operators ” covers the details of bitwise and bit shift operators, we’ll briefly summarize these operators in this tutorial.

7.1. The Bitwise AND Operator

The bitwise AND operator (&) returns the bit-by-bit AND of input values:

7.2. The Bitwise OR Operator

The bitwise OR operator (|) returns the bit-by-bit OR of input values:

7.3. The Bitwise XOR Operator

The bitwise XOR (exclusive OR) operator (^) returns the bit-by-bit XOR of input values:

7.4. The Bitwise Complement Operator

The bitwise complement operator (~) is a unary operator. It returns the value’s complement representation, which inverts all bits from the input value:

7.5. The Left Shift Operator

Shift operators shift the bits to the left or right by the given number of times.

The left shift operator (<<) shifts the bits to the left by the number of times defined by the right-hand side operand. After the left shift, the empty space in the right is filled with 0.

Next, let’s left shift the number 12 twice:

n << x has the same effect of multiplying the number  n  with x power of two.

7.6. The Signed Right Shift Operator

The signed right shift operator (>>) shifts the bits to the right by the number of times defined by the right-hand side operand and fills 0 on voids left as a result.

We should note that the leftmost position after the shifting depends on the sign extension .

Next, let’s do “signed right shift” twice on the numbers 12 and -12 to see the difference:

As the second example above shows, if the number is negative, the leftmost position after each shift will be set by the sign extension.

n >> x has the same effect of dividing the number n by x power of two.

7.7. The Unsigned Right Shift Operator

The unsigned right shift operator (>>>) works in a similar way as the ‘>>’ operator. The only difference is that after a shift, the leftmost bit is set to 0 .

Next, let’s unsigned right shift twice on the numbers 12 and -12 to see the difference:

As we can see in the second example above, the >>> operator fills voids on the left with 0 irrespective of whether the number is positive or negative .

8. The “ instanceof ” Operator

Sometimes, when we have an object, we would like to test if it’s an instance of a given type . The “ instanceof ” operator can help us to do it:

9. Assignment Operators

We use assignment operators to assign values to variables. Next, let’s see which assignment operators we can use in Java.

9.1. The Simple Assignment Operator

The simple assignment operator (=) is a straightforward but important operator in Java. Actually, we’ve used it many times in previous examples. It assigns the value on its right to the operand on its left:

9.2. Compound Assignments

We’ve learned arithmetic operators. We can combine the arithmetic operators with the simple assignment operator to create compound assignments.

For example, we can write “ a = a + 5 ” in a compound way: “ a += 5 “.

Finally, let’s walk through all supported compound assignments in Java through examples:

10. Conclusion

Java provides many groups of operators for different functionalities. In this article, we’ve passed through the operators in Java.

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