COM212 Reading/Writing Files and Exceptions

0. Copy Test0.java from the web page.
Run Test0.java 
Comment out try & catch (plus the associated '{' and '}'), run it again and note the results.
Return Test0.java to its original state.

1. Create Test1.java from Test0.java
> cp Test0.java Test1.java
Modify Test1.java to use it to create a file called input.txt consisting of 3 integers.

2. Create Test2.java from Test1.java
Modify Test2.java to read the three integers from input.txt and write them to output.txt.

3. Create Test3.java from Test2.java
Modify Test3.java to use a loop to read input.txt and write to output.txt.
Use a while loop with in.hasNextLine() to check for the end of file.
Modify so that the output ints are double the input.
Edit input.txt to try it with an improper input.
Add another exception handler.

4. Create Test4.java from Test3.java
Rewrite Test4.java so that you are using a static method that recursively does your iteration.  
Try it with a corrected input.txt.

5. Create Test5.java from Test4.java
Change Test5.java so that the user can enter the numbers.  
Use an exception to stop when there is an invalid entry.
Make sure you get a proper output on your correct entries.

6. Create Test6.java from Test5.java
Modify Test6.java so you can enter a name and number and the number still gets doubled.  
Prompt the user for the name and number.  
Stop the program when a return is entered at the name prompt.

7. Create Test7.java from Test3.java
Create a file named file.txt.
Using emacs (text editor) enter 5 integers in a column.  
Modify Test7.java so that if reads the five in, doubles each, and stores it in an array.  
Then save the new array to file.txt.
The result of running the program will be to double all the numbers in file.txt
You can assume file.txt will always have 5 numbers.