Final answer:
The statement that the class JFrame contains the method setSize is true. The setSize method is used in Java's JFrame to set the dimensions of a GUI window in pixels. It's an essential part of customizing and displaying a GUI properly in Java applications.
Step-by-step explanation:
The statement that the class JFrame contains the method setSize is true. In the Java programming language, JFrame is a part of the javax.swing package and is used to create a window on which components like labels, buttons, text fields, etc., can be added to create a graphical user interface (GUI). The method setSize is one among many provided by the JFrame class to control the behavior and appearance of the window.
To adjust the size of a JFrame, the setSize method can be called with two integer arguments that specify the width and height of the window in pixels. For example, calling frame.setSize(400, 300) would set the frame's size to 400 pixels wide by 300 pixels tall. This method is crucial when laying out a GUI, as it helps to ensure that all components within the JFrame are properly displayed to the user.
Moreover, it is important to note that the setSize method does not only set the size but can also be used in conjunction with other methods like setLocation to set the initial position of the frame, and setVisible, which makes the frame visible to the user once all components are added and laid out properly. Thus, the setSize method is an essential part of creating a functional and well-presented GUI in Java applications.