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Is there any way to delete entries of an arraylist dynamically

As you can see from the image below I want to select something from my table ( which changes whenever I press a button from the vertical box to the left i.e "Overview", "Orders" ... ) and delete the record from an array ( i.e. where the content comes from ).
The method I approached bellow works but it is not elegant since I have to create at most 8 if statements for each button id. Is there any way to delete the content dynamically. Is there any way for the JVM to figure out which record belongs to which array list?
TableController
#FXML
private TableView<Object> defaultTableView;
public void delete(){
if( MockServer.getServer().currentButton.equals("btnIngredients"))
MockServer.getServer().removeIngredient(defaultTableView.getSelectionModel().getSelectedItem());
else if ( MockServer.------.equals("btnOrders"))
MockServer.getServer().removeOrder(defaultTableView.getSelectionModel().getSelectedItem());
}
Controller
#FXML
private TableController tableController;
#FXML
public void deleteRecord(ActionEvent event){
tableController.delete();
}
MockServer
public class MockServer implements ServerInterface {
public Restaurant restaurant;
public ArrayList<Dish> dishes = new ArrayList<Dish>();
public ArrayList<Drone> drones = new ArrayList<Drone>();
public ArrayList<Ingredient> ingredients = new ArrayList<Ingredient>();
public ArrayList<Order> orders = new ArrayList<Order>();
public ArrayList<Staff> staff = new ArrayList<Staff>();
public MockServer(){}
public ArrayList<Ingredient> getIngredients() { return this.ingredients; }
public ArrayList<Order> getOrders() { return this.orders; }
public ArrayList<Staff> getStaff() { return this.staff; }
....
static public ServerInterface getServer(){
return server;
}
#Override
public void removeIngredient(Ingredient ingredient) {
int index = this.ingredients.indexOf(ingredient);
this.ingredients.remove(index);
this.notifyUpdate();
}
}

This pseudocode will need refactoring since I don't have all the code that you are using but I wish that you will get the general idea
Ok I believe that in the button click code you have to tell your mock server which list is currently used try adding this to the mock server
List currentList = null;
public void setCurrentList(String listName) { // you can use integer but the best is to use enum type setCurrentList(enum) this way you will get tapeSafety
switch(listName){
case "ingredients" : currentList = ingredients ; break;
//other cases
default : throw new Exception(" list not referred error with key value"+listName);
}
}
public void delete(Object o){
int index = this.currentList.indexOf(o);
this.currentList.remove(index);
}
now you can update you controller delete as bellow
public void delete(){
MockServer.getServer().delete(defaultTableView.getSelectionModel().getSelectedItem());
}
Why this should work?
you have to know that there is a good practice that says code to an interface, not an implementation
As you know List in java is an interface so when I assigned the ingredients object this interface will reference the same ArrayList as the object and it will take all it behaviours (how to search for an ingredient object etc...) this way when we will use the currentList on runtime after a button click we are sure that the currentList will be the same as the clicked list and pointing to the same list in the memory
Wish this simple and really resume explanation could help you

Create JTable rendering method which can be called by another class

I have a JFrame which has a JTable and it can represent data from database. Everything is fine but I want to load or refresh it from another class after a delete operation.
I have already done the delete operation but I can not load the JTable from another class. My code is below:
scrollPane = new JScrollPane();
add(scrollPane, BorderLayout.CENTER);
DefaultTableModel model=null;
try {
model = makeTableModel();
} catch (SQLException | IOException e) {
e.printStackTrace();
}
table = new JTable(model);
table.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent arg0) {
int row = table.getSelectedRow();
String getvalue = (table.getModel().getValueAt(row, 4).toString());
PopulatePhotographerClass pp=new PopulatePhotographerClass(getvalue);
}
});
table.setRowHeight(200);
scrollPane.setViewportView(table);
Here is my makeTableModel method:
public static DefaultTableModel makeTableModel() throws SQLException, IOException {
DefaultTableModel model = new DefaultTableModel(new String[]{"Image", "Name","Address","mobile-Number","NID"}, 0) {
#Override
public Class<?> getColumnClass(int columnIndex) {
return columnIndex == 0 ? Icon.class : super.getColumnClass(columnIndex);
}
};
String cmd = "select * from photographer_lookup";
try (Connection con =database.DbConnect.getconnection()) {
try (PreparedStatement stmt = con.prepareStatement(cmd)) {
try (ResultSet rs = stmt.executeQuery()) {
while (rs.next()) {
String name = rs.getString(3);
Blob blob = rs.getBlob(1);
String address=rs.getString("address");
String mobile=rs.getString("mobile_number");
String nid=rs.getString("Nid");
ImageIcon icon = null;
try (InputStream is = blob.getBinaryStream()) {
BufferedImage img = ImageIO.read(is);
icon = new ImageIcon(img);
}
model.addRow(new Object[]{icon,name,address,mobile,nid});
}
}}}
return model;
}
This is my code that I wrote. Now I want to define a method that does all work which is mentioned above and also it will be called by another class.

First off, you are making a mistake in using view indices to index the model. Listeners and all methods from JTable that return row or column indices will report view indices (except convertXXXIndexToModel methods).
As the table is sorted or columns are moved around, view indices will differ from model indices. JTable will not sort the model or rearrange columns in the model, rather it will change its mapping to the model.
If what you have is view indices and you want to look up cell values, either
Use JTable.getValueAt, which takes view indices
First convert view indices to model indices using JTable.convertRowIndexToModel and JTable.convertColumnIndexToModel before indexing in the model (JTable.getModel()).
Your mouse listener should read:
table.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent arg0) {
int row = table.getSelectedRow();
if( row < 0 ) return; // check if a row is selected first!
String getvalue = table.getValueAt(row, table.convertColumnIndexToView( 4 ) ).toString(); // use table.getValueAt, this getter takes view indices! Use convertColumnIndexToView to get a view index from a model index!
PopulatePhotographerClass pp=new PopulatePhotographerClass(getvalue);
}
});
Better still would be to implement a ListSelectionListener to listen for selection events, rather than using a MouseListener to act on selection events (thanks #mKorbel for pointing that out). This way you would be notified directly on list selection changes.
If you want operations to be done from another class, write a public method in your class that extends JFrame that does this work. If you have an instance to this class in another class, simply call this newly created public method.
Suppose your JFrame class is called MyFrameWithJTable
public class MyFrameWithJTable extends JFrame {
public void doSomeWork( /*parameters required in the operation*/ ) {
// Does the work you want to call from another class
// Eg the updates you want done in the JTable's model
}
}
Then in another class, if you have an instance of the MyFrameWithJTable class you can do
public class AnotherClass {
private MyFrameWithJTable instance;
public AnotherClass( MyFrameWithJTable instance ) {
this.instance = instance;
}
public void someMethod( ) {
instance.doSomeWork( /*supply parameters*/ );
}
}

Not able to sort CellTable Column

Trying to make my CellTable Colum sortable but I'm not getting it to work. I'm having an MVP application which gets data from a rest service. To show the data within the table works fine but to sort is doesn't work.
public class LicenseUsageUserViewImpl<T> extends Composite implements LicenseUsageUserView<T> {
#UiTemplate("LicenseUsageUserView.ui.xml")
interface LicenseDataViewUiBinder extends UiBinder<ScrollPanel,LicenseUsageUserViewImpl> {}
private static LicenseDataViewUiBinder uiBinder = GWT.create(LicenseDataViewUiBinder.class);
#UiField
CellTable<GWTLicenseUser> licenseUserCellTable;
List<GWTLicenseUser> licenseUsers;
ListDataProvider<GWTLicenseUser> dataProvider;
public List<GWTLicenseUser> getLicenseUsers() {
return licenseUsers;
}
public void setLicenseUsers(List<GWTLicenseUser> licenseUsers) {
this.licenseUsers = licenseUsers;
}
#UiField Label header;
ListHandler<GWTLicenseUser> sortHandler;
public LicenseUsageUserViewImpl() {
initWidget(uiBinder.createAndBindUi(this));
initCellTable();
}
#Override
public void setLicenseUsersTable(List<GWTLicenseUser> tmpLicenseUsers) {
if (tmpLicenseUsers.isEmpty()) {
licenseUserCellTable.setVisible(false);
} else {
setLicenseUsers(tmpLicenseUsers);
licenseUserCellTable.setWidth("100%");
licenseUserCellTable.setVisible(true);
licenseUserCellTable.setPageSize(getLicenseUsers().size());
licenseUserCellTable.setRowCount(getLicenseUsers().size(), false);
licenseUserCellTable.setRowData(0, getLicenseUsers());
licenseUserCellTable.setVisibleRange(new Range(0, licenseUserCellTable.getRowCount()));
sortHandler.setList(getLicenseUsers());
dataProvider.getList().clear();
dataProvider.getList().addAll(getLicenseUsers());
}
}
#Override
public void initCellTable() {
sortHandler = new ListHandler<GWTLicenseUser>(getLicenseUsers());
licenseUserCellTable.addColumnSortHandler(sortHandler);
licenseUserCellTable.setWidth("100%");
licenseUserCellTable.setVisible(true);
licenseUserCellTable.setVisibleRange(new Range(0, licenseUserCellTable.getRowCount()));
// Create a data provider.
dataProvider = new ListDataProvider<GWTLicenseUser>();
// Connect the table to the data provider.
dataProvider.addDataDisplay(licenseUserCellTable);
licenseUserCellTable.setWidth("100%");
licenseUserCellTable.setAutoHeaderRefreshDisabled(true);
licenseUserCellTable.setAutoFooterRefreshDisabled(true);
// userID
TextColumn<GWTLicenseUser> userIdColumn = new TextColumn<GWTLicenseUser>() {
#Override
public String getValue(GWTLicenseUser object) {
if (object != null ){
return object.getUserId();
} else {
return "NULL";
}
}
};
userIdColumn.setSortable(true);
sortHandler.setComparator(userIdColumn, new Comparator<GWTLicenseUser>() {
#Override
public int compare(GWTLicenseUser o1, GWTLicenseUser o2) {
return o1.getUserId().compareTo(o2.getUserId());
}
});
licenseUserCellTable.addColumn(userIdColumn, "User ID");
// more column entries
licenseUserCellTable.getColumnSortList().push(userIdColumn);
licenseUserCellTable.getColumnSortList().push(countColumn);
licenseUserCellTable.addColumnSortHandler(sortHandler);
}
}
setLicenseUsersTable is called from my activity with the response list of my users. When I start my application and make a rest call my data is provide and put into my list also shown within the CellTable but its not sortable, but I have this sort icon before my colum name. I figured I post the whole code because I think its know easier to see what I'm trying to do.
Thanks for any help.

Remove this line:
sortHandler.setList(getLicenseUsers());
You already passed a List into the SortHandler constructor in
sortHandler = new ListHandler<GWTLicenseUser>(getLicenseUsers());
Also, instead of
setLicenseUsers(tmpLicenseUsers);
you may need to use
licenseUsers.addAll(tmpLicenseUsers);
I hope one of them fixes the problem.

GWT Editors - how to add N sub-editors of the same type based on a Collection

I have an object, Supply, that can either be an ElecSupply or GasSupply (see related question).
Regardless of which subclass is being edited, they all have a list of BillingPeriods.
I now need to instantiate N number of BillingPeriodEditors based on the contents of that list, and am pretty baffled as to how I should do it.
I am using GWTP. Here is the code of the SupplyEditor I have just got working:
public class SupplyEditor extends Composite implements ValueAwareEditor<Supply>
{
private static SupplyEditorUiBinder uiBinder = GWT.create(SupplyEditorUiBinder.class);
interface SupplyEditorUiBinder extends UiBinder<Widget, SupplyEditor>
{
}
#Ignore
final ElecSupplyEditor elecSupplyEditor = new ElecSupplyEditor();
#Path("")
final AbstractSubTypeEditor<Supply, ElecSupply, ElecSupplyEditor> elecSupplyEditorWrapper = new AbstractSubTypeEditor<Supply, ElecSupply, ElecSupplyEditor>(
elecSupplyEditor)
{
#Override
public void setValue(final Supply value)
{
setValue(value, value instanceof ElecSupply);
if(!(value instanceof ElecSupply))
{
showGasFields();
}
else
{
showElecFields();
}
}
};
#Ignore
final GasSupplyEditor gasSupplyEditor = new GasSupplyEditor();
#Path("")
final AbstractSubTypeEditor<Supply, GasSupply, GasSupplyEditor> gasSupplyEditorWrapper = new AbstractSubTypeEditor<Supply, GasSupply, GasSupplyEditor>(
gasSupplyEditor)
{
#Override
public void setValue(final Supply value)
{
setValue(value, value instanceof GasSupply);
if(!(value instanceof GasSupply))
{
showElecFields();
}
else
{
showGasFields();
}
}
};
#UiField
Panel elecPanel, gasPanel, unitSection;
public SupplyEditor()
{
initWidget(uiBinder.createAndBindUi(this));
gasPanel.add(gasSupplyEditor);
elecPanel.add(elecSupplyEditor);
}
// functions to show and hide depending on which type...
#Override
public void setValue(Supply value)
{
if(value instanceof ElecSupply)
{
showElecFields();
}
else if(value instanceof GasSupply)
{
showGasFields();
}
else
{
showNeither();
}
}
}
Now, as the list of BillingPeriods is a part of any Supply, I presume the logic for this should be in the SupplyEditor.
I got some really good help on the thread How to access PresenterWidget fields when added dynamically, but that was before I had implemented the Editor Framework at all, so I think the logic is in the wrong places.
Any help greatly appreciated. I can post more code (Presenter and View) but I didn't want to make it too hard to read and all they do is get the Supply from the datastore and call edit() on the View.
I have had a look at some examples of ListEditor but I don't really get it!

You need a ListEditor
It depends of how you want to present them in your actual view, but the same idea apply:
public class BillingPeriodListEditor implements isEditor<ListEditor<BillingPeriod,BillingPeriodEditor>>, HasRequestContext{
private class BillingPeriodEditorSource extends EditorSource<BillingPeriodEditor>{
#Override
public EmailsItemEditor create(final int index) {
// called each time u add or retrive new object on the list
// of the #ManyToOne or #ManyToMany
}
#Override
public void dispose(EmailsItemEditor subEditor) {
// called each time you remove the object from the list
}
#Override
public void setIndex(EmailsItemEditor editor, int index) {
// i would suggest track the index of the subeditor.
}
}
private ListEditor<BillingPeriod, BillingPeriodEditor> listEditor = ListEditor.of(new BillingPeriodEditorSource ());
// on add new one ...
// apply or request factory
// you must implement the HasRequestContext to
// call the create.(Proxy.class)
public void createNewBillingPeriod(){
// create a new one then add to the list
listEditor.getList().add(...)
}
}
public class BillingPeriodEditor implements Editor<BillingPeriod>{
// edit you BillingPeriod object
}
Then in you actual editor edit as is in the path Example getBillingPeriods();
BillingPeriodListEditor billingPeriods = new BillingPeriodListEditor ();
// latter on the clickhandler
billingPeriods.createNewBillingPeriod()
You are done now.

ComboBoxModel events not working

I seem not to grasp the concept of Events and such. After reading a while on how to implement the listeners and such I came across the Java tutorial saying I should extend AbstractListModel to get the data event firing. For some reason it still doesn't work.
Is there anything I'm doing wrong?
And what kind of code is expected at addListDataListener(ListDataListener l) for it to work? Since I don't understand that either.
public class CarComboBox extends AbstractListModel<Object> implements ComboBoxModel<Object> {
private JdbcRowSet jdbc;
private int size = 0;
private String selection;
public CarComboBox() {
try {
jdbc = new Query().getCarInfo();
jdbc.beforeFirst();
while (jdbc.next()) {
size++;
}
jdbc.beforeFirst();
}
catch (SQLException ex) {
System.err.println(ex.toString());
}
}
#Override
public void setSelectedItem(Object anItem) {
selection = (String) anItem;
}
#Override
public Object getSelectedItem() {
return selection;
}
#Override
public void addListDataListener(ListDataListener l) {
}
#Override
public void removeListDataListener(ListDataListener l) {
}
#Override
public int getSize() {
return size;
}
#Override
public String getElementAt(int index) {
try {
jdbc.absolute(index + 1);
return jdbc.getString(2);
}
catch (SQLException ex) {
System.out.println(ex.toString());
}
return null;
}
}
And to add a listener to the CarComboBox I do:
CarComboBox ccb = new CarComboBox();
ccb.addListDataListener(new ListDataListener()

I'm guessing that you are using the official tutorial.
However you should not touch ListModel and ComboBoxModel. Those are more advanced features you probably do not need.
The 4 examples in the tutorial do NOT use ListModel and ComboBoxModel.
If you use a standard JComboBox (no ListModel or ComboBoxModel), what happens is that when someone makes a selection, an ActionEvent is fired. This event is magically fired by Swing; you don't have to worry about how it is generated. However what is your responsibility is to have some (zero, one or more) objects being able to receive and do something about the ActionEvent:
public class MyClass implements ActionListener {
JComboBox comboBox = ...;
...
// You must register explicitly every ActionListener that you
// want to receive ActionEvent's from comboBox.
// Here we register this instance of MyClass.
comboBox.addActionListener(this);
...
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() instanceof JComboBox) {
System.out.println("MyClass registered an ActionEvent from a JComboBox.");
System.out.println("Selected: " +
((JComboBox) e.getSource()).getSelectedItem());
}
}
}
Note that if you don't have any other ActionEvent's fired by different Swing components you
can skip the if (e.getSource() instanceof JComboBox) since you know your ActionEvent always comes from a JComboBox.
In my example the JComboBox is inside MyClass, but it does not have to be:
JComboBox comboBox = ...;
MyClass myClass = ...;
comboBox.addActionListener(myClass);
...
comboBox.addActionListener(someOtherActionListener);

You don't need to override addListDataListener() and removeListDataListener() method. The AbstractListModel already take care of the listeners. Here is the implementation of AbstractListModel.addListDataListener():
public void addListDataListener(ListDataListener l) {
listenerList.add(ListDataListener.class, l);
}
The idea of abstract classes is that they do most of the work for you. Usually you only need to implement abstract methods.

XXListener and XXModel are different sides of the coin: the former is the observer to the latter which is the observable. The listener registers itself to the model when it wants to get notified on changes. It's the responsibility of the model to
manage its listeners (that's typically handled already by the AbstractXXModel, as already explained by #userWhateverNumber ;)
fire the notifications if appropirate: that's the part a custom model must take over, in your case
like
#Override
public void setSelectedItem(Object item) {
selection = item;
fireContentChanged(this, -1, -1);
}
Arguably (there are personal preferences around :-) you often don't need custom model implementations but can just as well re-use the provided DefaultXXModels. In your context and assuming the content of the resultset is immutable it might be an option to fill the default model with the data at construction time, like
DefaultComboBoxModel model = new DefaultComboBoxModel();
forEachRowInResultSet {
model.addElement(resultSet.getString(2));
}
If, on the other hand, the content changes then your model implementation is invalid anyway: the model must notify its listeners whenever something had changed
Object one = model.getElementAt(index);
Object other = model.getElementAt(index)
if (!one.equals(other)) {
listener must have received a contentsChanged
}