Posts tagged "cheat-sheet":

Java CheatSheet

Modern Java is a strongly-typed, eagery evaluated, case sensative, yet whitespace insensative language. It uses hierarchies of classes/types to structure data, but also has first-class support for functional-style algebraic datatypes.

Java programs are made up of ‘classes’, classes contain methods, and methods contain commands. To just try out a snippet of code, we can

• Open a terminal and enter jshell; then enter:

  1 + 2 // The jshell lets you try things out!
  
  // Say hello in a fancy way
  import javax.swing.*;
  JOptionPane.showMessageDialog(new JFrame(), "Hello, World!");
  
  

• Alternatively, in IntelliJ, click Tools then Groovy Console to try things out!
• Finally, VSCode allows arbitrary Java code to be sent to a jshell in the background(!) and it echoes the result in a friendly way.

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