The Java Tutorials have been written for JDK 8. Examples and practices described in this page don't take advantage of improvements introduced in later releases and might use technology no longer available.
See Dev.java for updated tutorials taking advantage of the latest releases.
See Java Language Changes for a summary of updated language features in Java SE 9 and subsequent releases.
See JDK Release Notes for information about new features, enhancements, and removed or deprecated options for all JDK releases.

Answers to Questions and Exercises: Variables

Answers to Questions

1. The term "instance variable" is another name for non-static field.
2. The term "class variable" is another name for static field.
3. A local variable stores temporary state; it is declared inside a method.
4. A variable declared within the opening and closing parenthesis of a method is called a parameter.
5. What are the eight primitive data types supported by the Java programming language? byte, short, int, long, float, double, boolean, char
6. Character strings are represented by the class java.lang.String.
7. An array is a container object that holds a fixed number of values of a single type.

Answers to Exercises

1. Create a small program that defines some fields. Try creating some illegal field names and see what kind of error the compiler produces. Use the naming rules and conventions as a guide.

   There is no single correct answer here. Your results will vary depending on your code.

2. In the program you created in Exercise 1, try leaving the fields uninitialized and print out their values. Try the same with a local variable and see what kind of compiler errors you can produce. Becoming familiar with common compiler errors will make it easier to recognize bugs in your code.

   Again, there is no single correct answer for this exercise. Your results will vary depending on your code.