ConstraintFixture is a variation of CalculateFixture that has an implied expected value of true (or false).

For example, the following ConstraintFixture table just has given columns and is checking the constraint that the ''a'' value is less than the ''b'' value:

|!-fitlibrary.specify.SucceedConstraint-!|
|a|b|
|1|2|
|2|5|

The two rows are colored green because the constraint is satisfied. For each value row, the method ''aB()'' is called in the class ''!-SucceedConstraint-!'', as follows:
----{{{public class SucceedConstraint extends ConstraintFixture {
	public boolean aB(int a, int b) {
		return a < b;
	}
}
}}}----
If the method returns ''true'' the row passes, otherwise it is colored red.

We can also have a fixture that expects the result to be false, such that a is '''not''' less than ''b'':

|!-fitlibrary.specify.FailConstraint-!|
|b|a|
|1|2|
|2|5|

The fixture class is as follow:
----{{{public class FailConstraint extends ConstraintFixture {
	public FailConstraint() {
		super(false);
	}
	public boolean bA(int b, int a) {
		return a < b;
	}
}
}}}----
Notice how it passes the expected value of ''false'' to the superclass.
---- * ''Copyright (c) 2004, 2005 Rick Mugridge, Rimu Research.''
 * ''Released under the terms of the GNU General Public License version 2 or later.''