Decision Making if statement in Java Programming Language
Table of Content:
if statement examples in java
Example 1: if statement
class IfExample {
public static void main(String[] args){
int number =2 ;
if(number > 0) {
System.out.println("number is positive");
}
}
}
Output
number is positive
Press any key to continue . . .
Example 2: if statement
class IfExample {
public static void main(String[] args){
int number = -2 ;
if(number < 0) {
System.out.println("number is Negative");
}
}
}
Output
number is Negative
Press any key to continue . . .
Example 3: if statement
public class IfExample {
public static void main(String[] args) {
int age=21;
if(age>20){
System.out.println("Age is greater than 20");
}
}
}
Output
Age is greater than 20
Press any key to continue . . .
Example 4: if statement
public class IfExample {
public static void main(String[] args) {
int age=15;
if(age>20){
System.out.println("Age is greater than 20");
}
}
}
Output
Press any key to continue . . .
Example 5: if statement
import java.util.Scanner;
public class IfExample {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("Enter an integer: ");
int number = input.nextInt();
if (number % 5 == 0)
System.out.println("Divisiable Five");
if (number % 2 == 0)
System.out.println("This is Even Number");
}
}
Output 1
Enter an integer:
10
Divisiable Five
This is Even Number
Press any key to continue . . .
Output 2
Enter an integer:
8
This is Even Number
Press any key to continue . . .
Output 3
Enter an integer:
13
Press any key to continue . . .
Example 6: if statement
public class IfExample {
public static void main(String[] args) {
int marks = 85;
String grade="fail";
if (marks >= 35) {
grade = "Pass";
}
if (marks < 35) {
grade = "Fail";
}
System.out.println("Grade = "+grade);
}
}
Output
Grade = Pass
Press any key to continue . . .
Example 7: We can have multiple conditions inside If
- We can use,
&&
||
operators in order to refine condition.
- && operator will check whether both left hand AND right-hand conditions are true or not.
- || operator will check whether both left hand OR right-hand conditions are true or not.
If First Condition is true then || operator will skip checking second condition.
If First Condition is false then || operator will check second condition if second condition is
true then overall if will follow true block otherwise it will not execute if block.
Example as: || operator
public class IfExample {
public static void main(String[] args) {
int marks = 85;
if(marks > 70 || marks < 90)
System.out.println("Class A");
}
}
Output
Class A
Press any key to continue . . .
Example as: && operator
public class IfExample {
public static void main(String[] args) {
int marks = 85;
if(marks > 70 && marks < 90)
System.out.println("Class A");
}
}
Output
Class A
Press any key to continue . . .
Explanation about some important points inside if statement
If First Condition is true then ||
operator will skip checking second condition.
public class IfExample {
public static void main(String[] args) {
int number1 = 5;
int number2 = 10;
if ((++number1 > 0) || (++number2 > 0))
{
System.out.println(number1);
System.out.println(number2);
}
}
}
Output
6
10
Press any key to continue . . .
Explanation
Example 1: if statement
class IfExample { public static void main(String[] args){ int number =2 ; if(number > 0) { System.out.println("number is positive"); } } }
Output
number is positive Press any key to continue . . .
Example 2: if statement
class IfExample { public static void main(String[] args){ int number = -2 ; if(number < 0) { System.out.println("number is Negative"); } } }
Output
number is Negative Press any key to continue . . .
Example 3: if statement
public class IfExample { public static void main(String[] args) { int age=21; if(age>20){ System.out.println("Age is greater than 20"); } } }
Output
Age is greater than 20 Press any key to continue . . .
Example 4: if statement
public class IfExample { public static void main(String[] args) { int age=15; if(age>20){ System.out.println("Age is greater than 20"); } } }
Output
Press any key to continue . . .
Example 5: if statement
import java.util.Scanner; public class IfExample { public static void main(String[] args) { Scanner input = new Scanner(System.in); System.out.println("Enter an integer: "); int number = input.nextInt(); if (number % 5 == 0) System.out.println("Divisiable Five"); if (number % 2 == 0) System.out.println("This is Even Number"); } }
Output 1
Enter an integer: 10 Divisiable Five This is Even Number Press any key to continue . . .
Output 2
Enter an integer: 8 This is Even Number Press any key to continue . . .
Output 3
Enter an integer: 13 Press any key to continue . . .
Example 6: if statement
public class IfExample { public static void main(String[] args) { int marks = 85; String grade="fail"; if (marks >= 35) { grade = "Pass"; } if (marks < 35) { grade = "Fail"; } System.out.println("Grade = "+grade); } }
Output
Grade = Pass Press any key to continue . . .
Example 7: We can have multiple conditions inside If
- We can use,
&&
||
operators in order to refine condition. - && operator will check whether both left hand AND right-hand conditions are true or not.
- || operator will check whether both left hand OR right-hand conditions are true or not. If First Condition is true then || operator will skip checking second condition. If First Condition is false then || operator will check second condition if second condition is true then overall if will follow true block otherwise it will not execute if block.
Example as: || operator
public class IfExample { public static void main(String[] args) { int marks = 85; if(marks > 70 || marks < 90) System.out.println("Class A"); } }
Output
Class A Press any key to continue . . .
Example as: && operator
public class IfExample { public static void main(String[] args) { int marks = 85; if(marks > 70 && marks < 90) System.out.println("Class A"); } }
Output
Class A Press any key to continue . . .
Explanation about some important points inside if statement
If First Condition is true then ||
operator will skip checking second condition.
public class IfExample { public static void main(String[] args) { int number1 = 5; int number2 = 10; if ((++number1 > 0) || (++number2 > 0)) { System.out.println(number1); System.out.println(number2); } } }
Output
6 10 Press any key to continue . . .
Explanation
In the above example there is two condition, in left side (++number1 > 0)
and in right side (++number2 > 0)
First condition (++number1 > 0)
is true so it skip out checking second
condition (++number2 > 0)
.
For that it increase the value of number1 which gives 6. Second condition is not checked for that the output is still 10.
If First Condition is false then ||
operator will check second condition
if second condition is true then overall if will follow true block
public class IfExample { public static void main(String[] args) { int number1 = 5; int number2 = 10; if ((++number1 < 0) || (++number2 > 0)) { System.out.println(number1); System.out.println(number2); } } }
Output
6 11 Press any key to continue . . .
Explanation
In the above example there is two condition one is left side (++number1 < 0)
and in right side (++number2 > 0)
First condition (++number1 < 0)
is false because number1 is grater than 0 and it
increment the value of number1
which gives 6 , as it is a false condition it goes to condition 2 (++number2 > 0)
.
And it increase the value of number2 which gives 11.
If First Condition is true then &&
operator will check second condition.
public class IfExample { public static void main(String[] args) { int number1 = 5; int number2 = 10; if ((++number1 > 0) && (++number2 > 0)) { System.out.println(number1); System.out.println(number2); } } }
Output
6 11 Press any key to continue . . .
Explanation
In the above example there is two condition, in left side (++number1 > 0)
and in right side (++number2 > 0)
First condition (++number1 > 0)
is true because number1 is grater than 0 and it incrase the value of number1
which gives 6 , as it is a true condition it goes to condition 2 (++number2 > 0)
.
And it increase the value of number2 which gives 11.
If First Condition is false then &&
operator will skip checking second condition.
public class IfExample { public static void main(String[] args) { int number1 = 5; int number2 = 10; if ((++number1 < 0) && (++number2 > 0)) { System.out.println(number1); System.out.println(number2); } } }
Output
Press any key to continue . . .
Explanation
In the above example there is two condition, in left side (++number1 < 0)
and in right side (++number2 > 0)
First condition (++number1 < 0)
is false because number1 is grater than 0 and
it skip checking second condition (++number2 > 0)
. So over all if block is false
for that it will not execute if block.