/**
* Returns true if the constraint can be added as a child node to the current constraint (the
* length of the constraint will not exceed a certain limit). In that case, also update the length
* of the current constraint.
*/
protected boolean checkAndUpdateLength(Constraint constraint) {
if (this.length + constraint.length <= WebEntitiesConfig.CONSTRAINT_MAX_LENGTH) {
this.length += constraint.length;
return true;
} else {
MyLogger.log(
MyLevel.USER_EXCEPTION,
"In Constraint.java: Constraint has reached its maximum length of "
+ WebEntitiesConfig.CONSTRAINT_MAX_LENGTH);
return false;
}
}
/**
* Returns true if there is a configuration of AtomicConstraints that makes this constraint
* evaluates to TRUE.
*/
public boolean exists() {
// Collect atomic constraints
ArrayList<AtomicConstraint> atomicConstraintsList = new ArrayList<AtomicConstraint>();
collectAtomicConstraints(atomicConstraintsList);
AtomicConstraint[] atomicConstraints = atomicConstraintsList.toArray(new AtomicConstraint[] {});
if (atomicConstraints.length >= WebEntitiesConfig.CONSTRAINT_MAX_ATOMIC_NUM) {
MyLogger.log(
MyLevel.USER_EXCEPTION,
"In Constraint.java: Constraint has too many atomic predicates ("
+ atomicConstraints.length
+ ").");
return false;
}
// Initialize the logicTable
boolean[] logicTable = new boolean[atomicConstraints.length];
for (int i = 0; i < logicTable.length; i++) logicTable[i] = true;
boolean stop = (logicTable.length == 0);
while (!stop) {
// Set the atomic constraints based on logicTable
HashMap<AtomicConstraint, Boolean> booleanTable = new HashMap<AtomicConstraint, Boolean>();
for (int i = 0; i < logicTable.length; i++)
booleanTable.put(atomicConstraints[i], logicTable[i]);
// Evaluate this constraint
boolean result = evaluate(booleanTable);
if (result) return true;
// Alter the logicTable
stop = true;
for (int i = 0; i < logicTable.length; i++) {
if (logicTable[i]) {
logicTable[i] = false;
for (int j = 0; j < i; j++) logicTable[j] = true;
stop = false;
break;
}
}
}
return false;
}
