Homework #1 – Java 211, Mendelsohn

Due: One week after lecture #1,  10 minutes before class begins.

DL Students have an additional day until 11:59 PM (Central time) for submission. 


TIP:  Always begin SMALL and SIMPLE.  Begin with an extremely simple program.  Compile and run it.  If it works begin adding extra functionality.


  1. Get the JDK installed on your machine.  Configuring it may be a bit of a pain, but persevere….


  1. Say you are about to take a road trip through the Canadian wilderness.  Create a class called ‘DistanceConvert’ that will convert miles to kilometers.  Feel free to modify the ‘TemperatureConvert’ class to make it work.  However, do not simply copy and paste the code.  You will benefit much more by typing it in yourself from scratch.

-          Comment your code

-          Use whitespace (but don’t overdo it…)

-          Use proper indenting


  1. Write a version called ‘BadDistanceConvert’ in which you demonstrate an example of a logic error.  Be sure to comment your code to indicate where the error is.
  1. Create a class called Geometry in which you have two variables, one called length and one called radius.  Your program should take the length variable and use it to calculate the volume of a cube.  The program should use the radius to calculate the volume and circumference of a sphere.  Output the values of all those variables. 

I strongly recommend that you complete questions 1 through 4 by Wednesday’s class. 

  1. Create a class that has some code in it that outputs all of the numbers from –100 to 0 to the screen on the same line with a space between in increments of 7.  For 2 extra points, separate each number by a comma (but there should be no comma after the last number).  You must use a loop!

-100 –93 -86, etc


Bonus version:  -100, -93, …



  1. Create a class in which you have a variable called ‘number’.  You should test to see if the number is evenly divisible by 3, 4, or 5.  If it is, output that information to the screen.  Otherwise, output that it isn’t.  Your output should look identical to mine (except for the value of ‘number’). 

The value of ‘number’ is 20. 

20 is not evenly divisible by 3.

20 is evenly divisible by 4.

20 is evenly divisible by 5. 



  1. Write a program in which you have a variable with a randomly generated number between 1 and 25 (see below).  If the number is evenly divisible by 3, output to the screen “Divisible by 3”.  Otherwise, output “Not divisible by 3”.  (Hint: To determine whether a number is evenly divisible by another, take a look at the arithmatic operators discussed in lecture)  Next, modify your program to generate a random number 20 times.  Output each of the numbers and also how many of them were and were not evenly divisible by 3. 



To generate a random number between 1 and 25 you can use the code below:

int num; 
num = (int) (Math.random() * 25) + 1; //will be discussed in lecture #3


Sample output for the completed problem:





-          All your programs should be commented, demonstrate proper use of whitespace and indentation.  Look at the programs in your book for examples of proper form. 

-          Submit the various files for your assignment as a ZIP file to COL.  If you do not know how to Zip files, you can view a rather detailed tutorial here.

-          At the top of your code, put your name, the filename, and homework problem.  All files submitted with your homework must follow this pattern:

//Your Name, Your Section

//File Name (e.g. DistanceConvert.java)

//Homework #1, Question 2



public class DistanceConvert