This lab builds on the technique presented in Lab 4.1, and uses it to validate structured data in a file.

The file numbers.text contains data in the following format:

header1 int1 int2  header2 int1 int2   

i.e., each line begins with a header value, followed by that number of integers. Your program's task is to print out the average of each of these sequences.

However, the file contents is often corrupted by the time it gets to your program, so the data must be validated. Here are the possible problems:

A header value of 0

A negative header value

An empty line

Fewer values than specified by the header

More values than specified by the header

Each of these situations must be detected and if present, an exception should be thrown, no average is calculated, and processing proceeds to the next sequence.

The name of your class should be DataChecker.

For example, if the file numbers.text contains:

3 1 2 3 0 1 12 -12 14 1 2 3 5 1 2 3 4 5 6 4 10 20 30 40 

the program should produce the following output:

The average of the values on line 1 is 2.0 *** Error (line 2): Line is empty - average can't be taken *** Error (line 3): Header value of 0 - average can't be taken The average of the values on line 4 is 12.0 *** Error (line 5): Corrupt line - negative header value *** Error (line 6): Corrupt line - fewer values than header *** Error (line 7): Corrupt line - extra values on line The average of the values on line 8 is 25.0 There were 3 valid lines of data There were 5 corrupt lines of data