import java.util.Optional;
public class Java8Tester {
public static void main(String args[]) {
Java8Tester java8Tester = new Java8Tester();
Integer value1 = null;
Integer value2 = new Integer(10);
//Optional.ofNullable - allows passed parameter to be null.
Optional<Integer> a = Optional.ofNullable(value1);
//Optional.of - throws NullPointerException if passed parameter is null
Optional<Integer> b = Optional.of(value2);
System.out.println(java8Tester.sum(a,b));
}
public Integer sum(Optional<Integer> a, Optional<Integer> b) {
//Optional.isPresent - checks the value is present or not
System.out.println("First parameter is present: " + a.isPresent());
System.out.println("Second parameter is present: " + b.isPresent());
//Optional.orElse - returns the value if present otherwise returns
//the default value passed.
Integer value1 = a.orElse(new Integer(0));
//Optional.get - gets the value, value should be present
Integer value2 = b.get();
return value1 + value2;
}
}
About Online Java Compiler
Try our Online Java Compiler (Version OpenJDK 11.0.17) to Edit, Run, and Share your Java Code directly from your browser. This online development environment provides you the latest version OpenJDK 11.0.17.
How to use Online Java Compiler?
Write and Execute Code
- Write your program (or, paste it) directly under the "Source Code" tab.
- If you want to save your program, go to the "Project" menu and save it.
- You can directly execute your program without saving it by clicking on on "Execute" button.
User Input
The latest version of Coding Ground allows to provide program input at run time from the termnial window exactly the same way as you run your program at your own computer. So simply run a program and provide your program input (if any) from the terminal window available in the right side.
Online Java Compiler: Keyboard Shortcuts
The following are the keyword shortcut of this Online Java Compiler:
Shortcut | Description |
⌘ + Enter | Run the program |
⌘ + S | Save Project (Login Required) |
⇧ + ⌘ + S | Save As Project |
⌘ + P | New Project |
⌘ + G | Share Project |
⌘ + Z | Undo Editing |
⌘ + Y | Redo Editing |
⌘ + A | Select All Text |
⌘ + X | Cut Selected Text |
⌘ + C | Copy Selected Text |
⌘ + V | Paste Copied Text |
⌘ + F | Search Text |
⌘ + ⌥ + F | Replace Text |
Shortcut | Description |
Ctrl + Enter | Run the program |
Ctrl + S | Save Project |
Shift + Ctrl + S | Save As Project |
Ctrl + G | Share Project |
Ctrl + Z | Undo Editing |
Ctrl + Y | Redo Editing |
Ctrl + A | Select All Text |
Ctrl + X | Cut Selected Text |
Ctrl + C | Copy Selected Text |
Ctrl + V | Paste Copied Text |
Ctrl + F | Search Text |
Ctrl + H | Replace Text |
Online Java Compiler: Save and Share Java Code (Project)
Save Java Project Online
You can save your Java Project with us so that you can access this project later on. To save a project you will need to create a login Id with us. So before you save a project, please create a login Id using a link given at the top right corner of this page.
Share Java Project Online
You can use this feature to share your Java Code with your teachers, classmates and colleagues. Just click Share Button and it will create a short link, which can be shared through Email, WhatsApp or even through Social Media. A shared link will be deleted if it has been passive for almost 3 months.
More Features of Online Java Compiler
- Theme – You can change the current editor's theme from the "Editor Theme" option under "Settings" menu.
- Font Size – You can change the font size of the editor /compiler from from the "Font Size" option under "Settings" menu.
- Tab Size – You can change the tab size from the "Tab Size" option under "Settings" Menu.
- Show/Hide Line Numbers – You can show/hide the line number with the code from the "Show Line Numbers" or "Hide Line Numbers" option under "Settings" Menu.
- And, many more.
Benefits of Using Online Java Compiler
There are several benefits of using the Online Java Compiler to run your Java code:
- Platform independence: You can run your code from any device without taking care of operating systems.
- Convenience: You don't need to install anything for using this.
- No setup required: There is no need for additional setup to run your code.
- Updated version: Our online compiler/editors/terminals are the latest up-to-date.