Question

Fill in the blanks in each of the following statements: a) Class _____ of the Java 2 D API is used to draw ovals. b) Methods draw and fill of class Graphics2D require an object of type_________as their argument. c) The three constants that specify font style are _______, _________and______ d) Graphics2D method _________sets the painting color for Java 2D shapes.

Short answer

a) Ellipse2D; b) Shape; c) Font.PLAIN, Font.ITALIC, Font.BOLD; d) setPaint.

Step-by-step solution

Identifying Java 2D Class for Ovals

In Java 2D API, to draw shapes such as ovals, you use a class that provides methods specifically for those shapes. The class designed for drawing elliptical shapes, including ovals, is the `Ellipse2D` class.

Method Argument Type

The `draw` and `fill` methods in the `Graphics2D` class require an argument that specifies the shape to be drawn or filled. This argument must be an object of type `Shape`, which includes various implementations like `Rectangle2D`, `Ellipse2D`, etc.

Specifying Font Styles

Java uses constants to define font styles in the `Font` class. The three constants used to specify the style of a font are `Font.PLAIN`, `Font.ITALIC`, and `Font.BOLD`. These constants allow you to set the style of text rendered with `Font` objects.

Setting Painting Color

To set the color used for painting any shape or text in Java 2D, the `Graphics2D` class provides a method called `setPaint`. This method takes a `Color` object as an argument, which determines the color applied to any subsequent drawing operations.

Key concepts

Ellipse2D class

To draw ovals or any kind of elliptical shapes in Java, the `Ellipse2D` class from the Java 2D API is your best friend. This class is a part of the `java.awt.geom` package, which provides a way to create and manipulate various geometric shapes.

Using `Ellipse2D`, you can create an oval by specifying its position and dimensions. The shape is defined by a bounding rectangle, which you set by providing the x and y coordinates for its top-left corner, along with the width and height. These values allow precise control over the shape's size and placement on a canvas.

This class is crucial when you want to incorporate more sophisticated graphics into your application, as it provides both flexibility and power when drawing 2D shapes.

Graphics2D methods

The `Graphics2D` class, which extends the `Graphics` class, is responsible for most of the 2D rendering in Java. It contains powerful methods like `draw` and `fill` that allow you to render various shapes on a surface.

To use these methods effectively, you must pass an object that implements the `Shape` interface. This interface is a common contract for all geometry-based objects in Java's geometric packages, like `Ellipse2D`, `Rectangle2D`, and `Path2D`.

The `draw` method is used to outline the designated shape, whereas the `fill` method colors its interior. By using these methods, you can create complex scenes composed of numerous geometric shapes. These methods are a cornerstone of creating high-quality, visually appealing Java applications.

Java font styles

Java provides specific constants to define font styles, which are housed within the `Font` class found in the `java.awt` package. These constants are `Font.PLAIN`, `Font.BOLD`, and `Font.ITALIC`. They depict how your text will appear on the interface of your Java application.

- `Font.PLAIN` renders text without any special styling. - `Font.BOLD` applies a thicker face to the text, adding emphasis or importance. - `Font.ITALIC` slants the text for a more stylized look.

You can combine these constants by using the bitwise OR operator if you need more than one style. For example, `Font.BOLD | Font.ITALIC` creates a text style that is both bold and italicized. Understanding and applying these styles can significantly enhance the textual appearance in your applications.

setPaint method

The `setPaint` method, part of the `Graphics2D` class, is essential for setting the color used in drawing operations. This method affects anything you draw afterward, coloring shapes, text, or anything rendered on the graphics context.

You typically use a `Color` object from the `java.awt` package as the argument for `setPaint`. The `Color` class allows you to create various colors using predefined constants like `Color.RED` or by specifying RGB (Red, Green, Blue) values.

Using this method ensures that your graphics context uses the specified color for subsequent drawing operations. This flexibility allows you to change colors dynamically depending on the needs of your application, giving your 2D drawings an added layer of complexity and customization.