/**
* 给节点添加一个转移路径<br>
* Adds a _transition path starting from a specific node in the MDAG.
*
* @param originNode the MDAGNode which will serve as the start point of the to-be-created
* _transition path
* @param str the String to be used to create a new _transition path from {@code originNode}
*/
private void addTransitionPath(MDAGNode originNode, String str) {
if (!str.isEmpty()) {
MDAGNode currentNode = originNode;
int charCount = str.length();
// Loop through the characters in str, iteratevely adding
// a _transition path corresponding to it from originNode
for (int i = 0; i < charCount; i++, transitionCount++) {
char currentChar = str.charAt(i);
boolean isLastChar = (i == charCount - 1);
currentNode = currentNode.addOutgoingTransition(currentChar, isLastChar);
charTreeSet.add(currentChar);
}
/////
} else originNode.setAcceptStateStatus(true);
}
/**
* Removes a String from the MDAG.
*
* @param str the String to be removed from the MDAG
*/
public void removeString(String str) {
if (sourceNode != null) {
// Split the _transition path corresponding to str to ensure that
// any other _transition paths sharing nodes with it are not affected
splitTransitionPath(sourceNode, str);
// Remove from equivalenceClassMDAGNodeHashMap, the entries of all the nodes in the
// _transition path corresponding to str.
removeTransitionPathRegisterEntries(str);
// Get the last node in the _transition path corresponding to str
MDAGNode strEndNode = sourceNode.transition(str);
if (strEndNode == null) return;
if (!strEndNode.hasTransitions()) {
int soleInternalTransitionPathLength = calculateSoleTransitionPathLength(str);
int internalTransitionPathLength = str.length() - 1;
if (soleInternalTransitionPathLength == internalTransitionPathLength) {
sourceNode.removeOutgoingTransition(str.charAt(0));
transitionCount -= str.length();
} else {
// Remove the sub-path in str's _transition path that is only used by str
int toBeRemovedTransitionLabelCharIndex =
(internalTransitionPathLength - soleInternalTransitionPathLength);
MDAGNode latestNonSoloTransitionPathNode =
sourceNode.transition(str.substring(0, toBeRemovedTransitionLabelCharIndex));
latestNonSoloTransitionPathNode.removeOutgoingTransition(
str.charAt(toBeRemovedTransitionLabelCharIndex));
transitionCount -= str.substring(toBeRemovedTransitionLabelCharIndex).length();
/////
replaceOrRegister(sourceNode, str.substring(0, toBeRemovedTransitionLabelCharIndex));
}
} else {
strEndNode.setAcceptStateStatus(false);
replaceOrRegister(sourceNode, str);
}
} else {
unSimplify();
}
}
