This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
<p align="center" className="text-base text-gray-600 font-medium">Working of Java if statement</p>
</div>
### Example 1: Java if Statement
```java
class IfStatement {
public static void main(String[] args) {
int number = 10;
// checks if number is less than 0
if (number < 0) {
System.out.println("The number is negative.");
}
System.out.println("Statement outside if block");
}
}
```
#### Output
```text
Statement outside if block
```
In the program, `number < 0` is `false`. Hence, the code inside the parenthesis is **skipped**.
<TipInfo>
**Note:** If you want to learn more about about test conditions, visit [Java Relational Operators](/docs/operators#3-java-relational-operators) and [Java Logical Operators](/docs/operators#4-java-logical-operators).
</TipInfo>
We can also use Java Strings as the test condition.
### Example 2: Java if with String
```java
class Main {
public static void main(String[] args) {
// create a string variable
String language = "Java";
// if statement
if (language == "Java") {
System.out.println("Best Programming Language");
}
}
}
```
#### Output
```text
Best Programming Language
```
In the above example, we are comparing two strings in the `if` block.
## 2. Java if...else (if-then-else) Statement
The `if` statement executes a certain section of code if the test expression is evaluated to `true`. However, if the test expression is evaluated to `false`, it does nothing.
In this case, we can use an optional `else` block. Statements inside the body of `else` block are executed if the test expression is evaluated to `false`. This is known as the **if-...else** statement in Java.
The syntax of the **if...else** statement is:
```java
if (condition) {
// codes in if block
}
else {
// codes in else block
}
```
Here, the program will do one task (codes inside if block) if the condition is true and another task (codes inside else block) if the condition is false.
## How the if...else statement works?
If the condition is true, the code inside the if block is executed, otherwise, code inside the else block is executed
Working of Java if-else statements
### Example 3: Java if...else Statement
```java
class Main {
public static void main(String[] args) {
int number = 10;
// checks if number is greater than 0
if (number > 0) {
System.out.println("The number is positive.");
}
// execute this block
// if number is not greater than 0
else {
System.out.println("The number is not positive.");
In the above example, we have a variable named `number`. Here, the test expression `number > 0` checks if `number` is greater than 0.
Since the value of the `number` is `10`, the test expression evaluates to `true`. Hence code inside the body of `if` is executed.
Now, change the value of the `number` to a negative integer. Let's say `-5`.
```java
int number = -5;
```
If we run the program with the new value of `number`, the output will be:
```text
The number is not positive.
Statement outside if...else block
```
Here, the value of number is `-5`. So the test expression evaluates to `false`. Hence code inside the body of `else` is executed.
## 3. Java if...else...if Statement
In Java, we have an if...else...if ladder, that can be used to execute one block of code among multiple other blocks.
```java
if (condition1) {
// codes
}
else if(condition2) {
// codes
}
else if (condition3) {
// codes
}
.
.
else {
// codes
}
```
Here, `if` statements are executed from the top towards the bottom. When the test condition is `true`, codes inside the body of that `if` block is executed. And, program control jumps outside the **if...else...if** ladder.
If all test expressions are `false`, codes inside the body of `else` are executed.
## How the if...else...if ladder works?
If the first test condition if true, code inside first if block is executed, if the second condition is true, block inside second if is executed, and if all conditions are false, the else block is executed
Working of if...else...if ladder
### Example 4: Java if...else...if Statement
```java
class Main {
public static void main(String[] args) {
int number = 0;
// checks if number is greater than 0
if (number > 0) {
System.out.println("The number is positive.");
}
// checks if number is less than 0
else if (number < 0) {
System.out.println("The number is negative.");
}
// if both condition is false
else {
System.out.println("The number is 0.");
}
}
}
```
#### Output
```text
The number is 0.
```
In the above example, we are checking whether `number` is **positive**, **negative**, or **zero**. Here, we have two condition expressions:
- `number > 0` - checks if `number` is greater than `0`.
- `number < 0` - checks if `number` is less than `0`.
Here, the value of `number` is `0`. So both the conditions evaluate to `false`. Hence the statement inside the body of `else` is executed.
<TipInfo>
**Note:** Java provides a special operator called **ternary operator**, which is a kind of shorthand notation of **if...else...if** statement. To learn about the ternary operator, visit [Java Ternary Operator](/docs/operators#java-ternary-operator).
</TipInfo>
## 4. Java Nested if..else Statement
In Java, it is also possible to use `if..else` statements inside an `if...else` statement. It's called the nested `if...else` statement.
Here's a program to find the largest of **3** numbers using the nested `if...else` statement.
### Example 5: Nested if...else Statement
```java
class Main {
public static void main(String[] args) {
// declaring double type variables
Double n1 = -1.0, n2 = 4.5, n3 = -5.3, largest;
// checks if n1 is greater than or equal to n2
if (n1 >= n2) {
// if...else statement inside the if block
// checks if n1 is greater than or equal to n3
if (n1 >= n3) {
largest = n1;
}
else {
largest = n3;
}
} else {
// if..else statement inside else block
// checks if n2 is greater than or equal to n3
if (n2 >= n3) {
largest = n2;
}
else {
largest = n3;
}
}
System.out.println("Largest Number: " + largest);
}
}
```
#### Output:
```text
Largest Number: 4.5
```
In the above programs, we have assigned the value of variables ourselves to make this easier.
However, in real-world applications, these values may come from user input data, log files, form submission, etc.
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Add if else statement docs #43
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
Uh oh!
There was an error while loading. Please reload this page.
Add if else statement docs #43
Filter by extension
Viewed files
Uh oh!
There was an error while loading. Please reload this page.
Uh oh!
There was an error while loading. Please reload this page.
There are no files selected for viewing