TreeItem set multiple children under a parent/child - javafx

Question

I am trying to get a list of equipment IDs to show under one data structure, instead of a listing with the equipment name alongside each ID.
I'm trying to get it to show:
Site Equipment
Inlet P1
M&C-SP2500
329
Sick Maihak-MCS 100e
330
336
538
Inlet P2
etc....
The data is from MySQL query and using an ObservableList.
private ObservableList<Customer_EquipTree> equiptrees;
TreeItem<String> rootItem = new TreeItem<String>("Site Equipment");
rootItem.setExpanded(true);
for (Customer_EquipTree equiptree : equiptrees) {
TreeItem<String> equip = new TreeItem<String>(equiptree.getEquipment());
TreeItem<String> clID = new TreeItem<String>(equiptree.getclID().toString());
boolean found = false;
for (TreeItem<String> siteDes : rootItem.getChildren()) {
if (siteDes.getValue().contentEquals(equiptree.getSiteDesignation())) {
siteDes.getChildren().add(equip);
equip.getChildren().add(clID);
found = true;
break;
}
}
if (!found) {
TreeItem<String> siteDes = new TreeItem<String>(equiptree.getSiteDesignation());
rootItem.getChildren().add(siteDes);
siteDes.getChildren().add(equip);
equip.getChildren().add(clID);
locationTreeView.setRoot(rootItem);
}
}
This is how I have
public class Customer_EquipTree {
private String SiteDesignation;
private String Equipment;
private Integer Checklistid;
private Integer clID;
public Customer_EquipTree(String SiteDesignation, String Equipment, Integer Checklistid, Integer clID) {
this.SiteDesignation = SiteDesignation;
this.Equipment = Equipment;
this.Checklistid = Checklistid;
this.clID = clID;
}
public String getSiteDesignation() {
return SiteDesignation;
}
public void setSiteDesignation(String SiteDesignation) {
this.SiteDesignation = SiteDesignation;
}
public String getEquipment() {
return Equipment;
}
public void setEquipment(String Equipment) {
this.Equipment = Equipment;
}
public Integer getChecklistid() {
return Checklistid;
}
public void setChecklistid(Integer Checklistid) {
this.Checklistid = Checklistid;
}
public Integer getclID() {
return clID;
}
public void setclID(Integer clID) {
this.clID = clID;
}
#Override
public String toString() {
return SiteDesignation + " " + Equipment.toString();
}
}

Answer 1

It seems to me that your Customer_EquipTree is basically a tuple of site, equipment and id and there is one for every id. It looks you need to look for existing equipment the same way you look for existing sites.
You should create a helper method for this to avoid code duplication:
public static <T> TreeItem<T> findOrInsert(TreeItem<T> parent, T childValue) {
for (TreeItem<T> child : parent.getChildren()) {
if (child.getValue().equals(childValue)) {
return child;
}
}
TreeItem<T> result = new TreeItem<T>(childValue);
parent.getChildren().add(result);
return result;
}
for (Customer_EquipTree equiptree : equiptrees) {
TreeItem<String> siteDes = findOrInsert(rootItem, equiptree.getSiteDesignation());
TreeItem<String> equip = findOrInsert(siteDes, equiptree.getEquipment());
equip.getChildren().add(new TreeItem<>(equiptree.getclID().toString()));
}
BTW: using ORDER BY in your sql query would allow you to simplify the tree creation a bit, since you can be sure the items with matching site/equipment values occur next to each other in the ResultSet, e.g.
TreeItem<String> rootItem = new TreeItem<String>("Site Equipment");
try (Statement st = conn.createStatement()) {
ResultSet rs = st.executeQuery("SELECT siteDesignation, equipment, clID FROM Customer_EquipTree ORDER BY siteDesignation, equipment");
String currentSite = null;
String currentEquipment = null;
TreeItem<Sting> tiSite = null;
TreeItem<String> tiEquipment = null;
while (rs.next()) {
String site = rs.getString(1);
String equipment = rs.getString(2);
String id = rs.getString(3);
if (!site.equals(currentSite)) {
currentSite = site;
tiSite = new TreeItem<>(site);
rootItem.getChildren().add(tiSite);
currentEquipment = null; // equipment needs to be replaced too
}
if (!equipment.equals(currentEquipment)) {
currentEquipment = equipment;
tiEquipment = new TreeItem<>(equipment);
tiSite.getChildren().add(tiEquipment);
}
tiEquipment.getChildren().add(new TreeItem<>(id));
}
}