Questions and Exercises: Object-Oriented Concepts - Java Tutorial 5.0 英文版

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Trail: Learning the Java Language
Lesson: Object-Oriented Programming Concepts

Questions and Exercises: Object-Oriented Concepts

Questions

Use the API documentation for the Java 2 Platform to answer the following questions.

The ClickMe component uses Color.BLACK when setting up its border. What other colors can you get by name like this?
How would you create a Color object to represent purple? (Hint: Purple is made up of equal parts of red and blue.)
Which Graphics method would you use to draw a filled square?
Which Graphics method would you use to draw text?

Exercises

Use what you've learned from the preceding questions to make the following modifications to the ClickMe component.
Note: The point of these exercises is to encourage you to read code and to use the API documentation. We haven't yet given you any detailed information about how to write code, but you might be surprised at how much you can do.

Modify ClickMe to draw a red square instead of a green spot.

Modify ClickMe to display your name in purple instead of a green spot.

Remember, to compile and use the ClickMe component, you need the files ClickMe.java, ClickMeApp.java, and Spot.java. You can run the program using the command java ClickMeApp.

Check your answers.

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