Introduction to Java Programming

• JDK stands for Java Development Kit
• The Java Virtual Machine (JVM) converts Java code into machine code
• A Java program consists of one or more classes, and each class contains one or more methods
• The main() method is the entry point for executing a Java program
• The output of the provided Java code is "Hello, Java!"
• A Java class is a collection of related variables and methods
• // This is a comment, /* This is a comment /, and /* This is a documentation comment **/ are all valid Java comments
• 123start is not a valid Java identifier
• The import statement includes external Java classes or libraries in a program
• int x = 10; is an example of a Java variable declaration
• GUI stands for Graphical User Interface
• The javax.swing package contains the Swing components
• AWT is heavyweight, while Swing is lightweight
• JComponent is the root class of all Swing components
• JFC stands for Java Foundation Classes
• JTextField is the Swing component to create a text box
• import javax.swing.; correctly imports the Swing package
• Java Swing's pluggable look-and-feel allows applications to change their appearance dynamically
• JButton is the Swing component to create a button
• Compiler is not a component of a GUI
• Java Swing components are considered Lightweight
• Component is the superclass of all AWT and Swing components
• JFrame is used to create a simple window in Swing
• The primary function of the JPanel class is to group other components together
• JComboBox allows users to select one item from a drop-down list
• setTitle("My Window"); is the correct method to set the title of a JFrame
• In Swing, the JPanel container is used to hold and arrange components
• The primary purpose of a JLabel is to display text or images
• JOptionPane creates a pop-up message in Swing
• "MVC" in Java Swing refers to Model-View-Controller
• A computer program is a sequence of instructions to perform a task
• Problem definition is the first step in the Programming Cycle
• An algorithm is a step-by-step procedure for solving a problem
• "It must have multiple outputs" NOT a characteristic of an algorithm
• Pseudocode is a way to describe an algorithm without using specific programming syntax
• "If student's grade is greater than or equal to 60, print 'Passed', else print 'Failed'" is an example of pseudocode
• Problem-solving steps in programming systematically develop a working solution

Pseudocode and Java Basics

• The main advantage of using pseudocode: easier to understand than real programming languages
• Java is a programming language
• James Gosling is the creator of Java

JFrame Methods and Behaviors

• setSize() is used to set the size of a JFrame
• setVisible(true); method in JFrame makes the frame visible
• setResizable(false); prevents the JFrame from being resized
• Default behavior when closing a JFrame: The frame disappears, but the program continues running
• setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE) terminates a program when the JFrame is closed
• A JPanel is primarily used for organizing components within a container

Containers

• JPanel container is lightweight
• JFrame is fully functional, while JDialog is not
• getTitle() returns the current title
• setBounds(int x, int y, int width, int height) defines the JFrame position and size
• setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE) prevents a user from closing a JFrame
• The default close operation of JFrame is HIDE_ON_CLOSE
• A JDialog mainly used for displaying messages and getting input
• The primary purpose of the JPanel class is to hold and group components together
• isResizable() checks if a JFrame is resizable
• A JFrame can be positioned at a specific location using setLocation(int x, int y)
• WindowConstants.DISPOSE_ON_CLOSE disposes the JFrame but keeps the program running
• A Frame is a complete window, while a Panel is just a container inside a window
• drawComponents() is NOT a method of the JFrame class

Text Components and Visibility

• String is the parameter type required for the setTitle() method
• setVisible(true); in a Swing application makes the window visible on the screen
• JTextField is for single-line input, while JTextArea is for multiple lines of text
• JMenuBar for creating menus
• addActionListener() is used to add an ActionListener
• java.awt.event is the base package for event handling in Java Swing
• A container class holds other components within it
• Button a not a type of container class
• The primary purpose of a JFrame: to create a graphical window
• setTitle() is used to set the title of a JFrame
• JFrame a fully functional window with icons and titles
• The JOptionPane creates dialog boxes for messages and user input
• showTableDialog() not a method of JOptionPane
• The showMessageDialog() displays a simple message with an "OK" button
• The showInputDialog() Asks the user for input

JOptionPane and Swing Components

• SUCCESS_MESSAGE is NOT a message type in JOptionPane
• showConfirmDialog() returns an integer representing the selected option
• ALL OF THE ABOVE is a valid option type in JOptionPane
• javax.swing package is needed to use JOptionPane
• JComponent is the root class of all Swing components
• JButton creates push buttons in Swing
• JTextComponent is the base class for all text-based components in Swing
• setText() sets the text of a JLabel
• JComboBox can create a drop-down list
• getSelectedItem() retrieves the selected item from a JComboBox
• JCheckBox allows a user to select multiple options independently
• isSelected() checks if a JCheckBox is selected
• JTextField is used for single-line text input
• JTextField(int columns) creates a JTextField with a specified number of columns
• The JCheckBox allows multiple selections, JRadioButton does not
• ButtonGroup is required to group multiple JRadioButton components together
• addItem() adds an item to a JComboBox
• setEditable(true) in a JComboBox allows users to type their own input
• JTextArea is used for entering multiple lines of text
• setFont() sets the font of a JTextArea
• setSelected() sets the state of a JCheckBox

AWT Fundamentals

• AWT stands for Abstract Window Toolkit
• java.awt package contains the AWT classes in Java
• Java AWT components are considered Platform-dependent
• JLabel is NOT an AWT component
• The Frame class in AWT creates a window with a title bar
• The function of TextArea in AWT is to allow input of multiple lines of text
• drawString() in AWT displays a string on the screen
• The drawLine() in AWT draws a straight line between two points
• The Graphics AWT class handles graphical operations
• drawOval() draws an oval in AWT
• The top-left coordinate of an AWT drawing area is (0,0)
• The fillRect() method in AWT draws a filled rectangle
• The default behavior of an AWT Window component is that it has no title bar
• Choice AWT component allows the user to choose a single option from a list
• drawPolygon() draws a polygon in AWT

AWT Components and Layout

• AWT components rely on Native Operating System (OS) subroutines
• A Panel in AWT: A generic container for holding components
• setVisible() is used to set the visibility of a component
• add() in AWT inserts a component into a container
• JLabel not a container in AWT
• Frame can exist independently, whereas Dialog needs a parent frame
• The default layout manager for Frame in AWT? BorderLayout
• The primary purpose of the Label class in AWT to display read-only text
• setSize(int width, int height) Sets the dimensions of a component
• setLayout() is to define the layout of a component