The JavaTM Tutorial

| Start of Tutorial > Start of Trail > Start of Lesson | Search Feedback Form

Trail: Learning the Java Language
Lesson: Language Basics

## Questions and Exercises: Control Flow

### Questions

> 1. Look at the `SortDemo` program. What control flow statements does it contain?
> 2. What's wrong with the following code snippet:

>    >     if (i = 1) {
>    >         /* do something */
>    >     }

> 3. Look at the `WhileDemo` program and the `DoWhileDemo` program. What would the output be from each program if you changed the value of each program's `copyFromMe` string to `golly gee. this is fun.` Explain why you think each program will have the predicted output.

### Exercises

> 1. Consider the following code snippet.

>    >     if (aNumber >= 0)
>    >         if (aNumber == 0) System.out.println("first string");
>    >     else System.out.println("second string");
>    >     System.out.println("third string");

>    1. What output do you think the code will produce if `aNumber` is 3?
>    2. Write a test program containing the code snippet; make `aNumber` 3. What is the output of the program? Is it what you predicted? Explain why the output is what it is. In other words, what is the control flow for the code snippet?
>    3. Using only spaces and line breaks, reformat the code snippet to make the control flow easier to understand.
>    4. Use braces { and } to further clarify the code and reduce the possibility of errors by future maintainers of the code.

Check your answers.

| Start of Tutorial > Start of Trail > Start of Lesson | Search Feedback Form

Copyright 1995-2004 Sun Microsystems, Inc. All rights reserved.