Java Reference
In-Depth Information
TIP: (continued)
It is sometimes impossible or inconvenient to test a method without using some
other method that has not yet been written or has not yet been tested. In this
case, you can use a simplified version of the missing or untested method. These
simplified methods are called
stubs
. These stubs will not necessarily perform the
correct calculation, but they will deliver values that suffice for testing, and they
are simple enough that you can have confidence in their performance. For example,
the following is a possible stub:
stub
/**
Computes the probability of rain based on temperature, barometric
pressure, and relative humidity. Returns the probability as a
fraction between 0 and 1.
*/
public double
rainChance(
double
temperature,
double
pressure,
double
humidity)
{
return
0.5;
//Not correct but good enough for a stub.
■
}
The Fundamental Rule for Testing Methods
Every method should be tested in a program in which every other method in the testing
program has already been fully tested and debugged.
Self-Test Exercises
13.
In the defi nition of
precedes
in Display 4.7 , we used
month.equals(otherDate.month)
to test whether two months are equal; but we used
getMonth() < otherDate.getMonth()
to test whether one month comes before another. Why did we use
month
in
one case and
getMonth
in another case?
14. What is the fundamental rule for testing methods?
