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Store products in a TreeSet and print the content in a JTable
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I'm trying to display a single JTable, but I keep getting many new JTables everytime I insert a new product: http://i.stack.imgur.com/gyNsn.png
How can I display just one JTable and also make the column names visible?
Here is the method that creates the table:
public JTable populate(Product p) {
Vector<Vector<Object>> data = new Vector<Vector<Object>>();
Vector<Object> row = new Vector<Object>();
Vector<String> headers = new Vector<String>();
headers.add("Product name");
headers.add("Price");
headers.add("In stock");
row.add(p.getProductName());
row.add(p.getPrice());
row.add(p.getStock());
data.add(row);
productsTable = new JTable(data, headers);
return (new JTable(data, headers));
}
And here is a part from the GUI class:
addProductBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Product product = new Product(insertProductName.getText(), Integer.parseInt(insertPrice.getText()), Integer.parseInt(insertStock.getText()));
warehouse.addProduct(product); // by using a TreeSet
productsTable = warehouse.populate(product); // here I call the earlier defined method
warehouse.initFile(); // I wrote the productsTable content into a binary file, so that it can act like a database
warehouse.readFile();
warehouse.populate(product);
manageProductsPanel.add(productsTable);
});
The populate method you posted creates a new JTable every time it is called. Given this is called every time the ActionListener is called, a new JTable will be added. You should consider creating your own TableModel - extend AbstractTableModel and override the necessary methods, returning the appropriate values for each row/column. A simple example is below, making some assumptions about project structure for demo's sake (for instance warehouse is an instance of a List):
public class MyTableModel extends AbstractTableModel{
#Override
public int getColumnCount() {
return 3;
}
#Override
public int getRowCount() {
return warehouse.size();
}
#Override
public Object getValueAt(int arg0, int arg1) {
switch(arg1){
case 0:
return warehouse.get(arg0).getName();
case 1:
return warehouse.get(arg0).getPrice();
default:
return warehouse.get(arg0).isInStock();
}
}
#Override
public String getColumnName(int col){
switch(col){
case 0:
return "Name";
case 1:
return "Price";
default:
return "In STock";
}
}
}
You can then create an instance of this class, and set the table model for the JTable. Every time the backed List is updated, you can update the Listeners of the TableModel
MyTableModel tableModel = new MyTableModel();
myTable.setMOdel(tableModel);
.......
//when an item is added to
warehouse.add(item);
tableModel.fireTableDataChanged();
There are more demonstrations for how to customize a JTable in the Oracle Tutorials
Related
I created a class that is meant to show a JTable populated with data taken from a database with hibernate:
public class FLlistes extends JInternalFrame {
private JTable table;
private DefaultTableModel model;
//some code for more components of the form
String[] columns = {"Id","Data", "Lloc"};
model = new DefaultTableModel(columns, 0) {
#Override
public Class<?> getColumnClass(int columna) {
if (columna == 2)
return LocalDate.class;
return Object.class;
}
#Override
public boolean isCellEditable(int row, int column) {
return false;
}
};
table = new JTable(model);
JScrollPane scrollPane = new JScrollPane();
scrollPane.setBounds(49, 176, 732, 361);
getContentPane().add(scrollPane);
scrollPane.setViewportView(table);
//some code for more components of the form
}
Then I have a class that makes the queries with hibernate. The next method is supposed to collect data from a table and populate the table I created before.
public class AccionsBD {
public static void GetAllLlistes() {
String jql = "select llc from LlistaCompra llc";
EntityManager entityManager = JPAUtil.getEntityManagerFactory().createEntityManager();
TypedQuery<LlistaCompra> q = entityManager.createQuery(jql,LlistaCompra.class);
List<LlistaCompra> llistes = q.getResultList();
FLlistes fl = new FLlistes();
for (LlistaCompra llista: llistes) {
System.out.println(llista.getIdLlista());
System.out.println(llista.getData());
System.out.println(llista.getLloc());
Object[] objFila = new Object[3];
objFila[0] = llista.getIdLlista();
objFila[1] = llista.getData();
objFila[2] = llista.getLloc();
fl.getModel().addRow(objFila);
}
entityManager.close();
}
}
The purpose of the System.out.println inside the loop is only to check that the query works. The query is working fine, I tried debugging and the end of the loop objFila contains all the correct data, but the table in the form never shows anything besides the table header. What am I missing?
Also, for some reason sometimes when I run the app the form shows up, and somtimes it doesn't. It does this without even changing the code. Why does this happen?
Edit: this is my getter:
public DefaultTableModel getModel() {
return model;
}
What I am trying to do is to populate a JTable from an ArrayList.
The array list is a type Record which I have defined below:
public class Record {
int Parameter_ID;
int NDC_Claims;
int NDC_SUM_Claims;
public Record(int parameter, int claims, int ndc_sum_claims){
Parameter_ID = parameter;
NDC_Claims = claims;
NDC_SUM_Claims = ndc_sum_claims;
}
public Record() {
// TODO Auto-generated constructor stub
}
I don't know how to populate the table with the column headers as well. This is what I have so far:
DefaultListModel listmodel = new DefaultListModel();
ArrayList<Record> test = new ArrayList<Record>();
DefaultTableModel modelT = new DefaultTableModel();
Object data1[] = new Object[3];
for(int i=0; i<test.size();i++){
data1[0] = test.get(i).Parameter_ID;
data1[1] = test.get(i).NDC_SUM_Claims;
data1[2] = test.get(i).NDC_Claims;
modelT.addRow(data1);
}
table_1 = new JTable(modelT, columnNames);
contentPane.add(table_1, BorderLayout.CENTER);
contentPane.add(table_1.getTableHeader(), BorderLayout.NORTH);
Nothing is outputted. Any help would be great!
Well you need to start by reading the API. You can't program if you don't read the API first.
DefaultTableModel modelT = new DefaultTableModel();
When you read the API what does that constructor do? It creates a model with 0 rows and 0 columns. You will want to create a model with 3 columns and 0 rows so that you can add rows of data to the model. Read the DefaultTableModel API
table_1 = new JTable(modelT, columnNames);
What does that statment do? I don't see a constructor that allows you to specify a model and column names so how does your code compile. You just want to create the table using
the model.
contentPane.add(table_1, BorderLayout.CENTER);
contentPane.add(table_1.getTableHeader(), BorderLayout.NORTH);
The table should be added to the viewport of a JScrollPane. The header will then be displayed as the column header of the scroll pane.
Read the JTable API. The API also has a link to the Swing tutorial on How to Use Tables you need to read for the basics.
ArrayList<Record> test = new ArrayList<Record>();
You create an empty ArrayList. So what do you expect to happen when you iterate through the loop? How can you add data to the model if there is no data in the ArrayList?
Also, did you search the forum/web for examples that use the DefaultTableModel or JTable classes. Those examples will help you write your code.
You can create a custom AbstractTableModel and then create a JTable using that model.
Here is a class handling ArrayList of Arrays:
import java.util.ArrayList;
import javax.swing.table.AbstractTableModel;
public class DataTableModel<T> extends AbstractTableModel {
/**
* Benjamin Rathelot
*/
private static final long serialVersionUID = -7361470013779016219L;
private ArrayList<T[]> data = new ArrayList<T[]>();
private String[] tableHeaders;
public DataTableModel(ArrayList<T[]> data, String[] headers) {
super();
this.data = data;
this.tableHeaders = headers;
}
#Override
public int getRowCount() {
return data.size();
}
#Override
public int getColumnCount() {
if(data.size()>0) return data.get(0).length;
return 0;
}
#Override
public Object getValueAt(int arg0, int arg1) {
// TODO Auto-generated method stub
if(data.size()>=arg0) {
if(data.get(arg0).length>=arg1) {
return data.get(arg0)[arg1];
}
}
return null;
}
#Override
public String getColumnName(int columnIndex) {
return tableHeaders[columnIndex];
}
}
So I try to populate jtable using my arraylist, I also want to keep 3-layer architecture
My DAL
I read data from file and try to populate it into table
public class E {
public ArrayList<String> getinformationforthetable() {
Scanner s = null;
ArrayList<String> data = new ArrayList<String>();
try {
s = new Scanner(new File("songs.txt"));
while (s.hasNextLine()) {
String line = s.nextLine();
if (line.startsWith("")) {
String[] atoms = line.split("[#]");
ArrayList<String> row = new ArrayList<String>();
row.add(atoms[0]);
row.add(atoms[1]);
row.add(atoms[2]);
row.add(atoms[3]);
row.add(atoms[4]);
row.add(atoms[5]);
data.addAll(row);
}
}
}
catch(IOException e) {
e.printStackTrace();
}
finally {
if (s != null) {
s.close();
}
}
return data;
}
}
My UI
I want to populate table model with arraylist I had before but im not sure how to do it.
public class setTableModel extends AbstractTableModel{
private static final String[] COLUMN_HEADERS =
{
"Title", "Artist", "Gengre", "Quality", "Duration","Favorite"
};
private static final Class[] COLUMN_TYPES =
{
String.class, String.class,String.class,String.class, Integer.class, Boolean.class
};
#Override
public int getRowCount() {
return COLUMN_HEADERS.length;
}
#Override
public int getColumnCount() {
return null;
//todo
}
#Override
public Object getValueAt(int i, int i1) {
return null;
//todo
}
}
Don't use an ArrayList.
String[] atoms = line.split("[#]");
//ArrayList<String> row = new ArrayList<String>();
model.addRow( atoms );
You already have the data in an Array. You can use the addRow(...) method of the DefaultTableModel which will take the data in the array and add the data to the model for you.
So change your method signature. Instead of returning an ArrayList you should return a DefaultTableModel. Then you can use the model to create your JTable.
A problem I can see you facing is the structure of your ArrayList. It is only one dimensional. Data in a JTable/TableModel needs to be two dimensional rows/columns
If you made your getinformationforthetable() return an ArrayList<ArrayList<String>> then you would be able to more easily populate your table.
Also you might as well just extends DefaultTableModel. I don't see any special functionality added to your AbstractTableModel. Then you can just use the method addRow of DefaultTableModel to add rows. Something like this
DefaultTableModel model = new MyDefaultTableModel();
E e = new E();
ArrayList<ArrayList<String>> list = e.getinformationforthetable();
for (ArrayList<String> row : list) {
model.addRow(row.toArray());
}
table.setModel(model);
Or don't even extend DefaultTableModel at all. You can just override it's getColumnClass(), something like this
private static final String[] COLUMN_HEADERS =
{
"Title", "Artist", "Gengre", "Quality", "Duration","Favorite"
};
DefaultTableModel model = new DefaultTableModel(COLUMN_HEADERS, 0) {
#Override
public Class getColumnClass(int column) {
switch (column) {
case 0: return String.class; break;
case 1: return String.class; break;
...
}
}
};
In your example, you need your setTableModel (which you should rename to SetTableModel to be consistent with Java style) to maintain the data. Currently, you're keeping the data in E.
You can add a method to SetTableModel like addRow(String) and that method can do the split and keep the data within SetTableModel.
Then when you override getValueAt(int row, int column), you pull from the local data.
Also, getColumnCount() could return COLUMN_HEADERS.length and getRowCount() should return the number of rows maintained in the local data.
I created a Java GUI that displays the table using the following syntax:
table = new JTable(new MyTableModel(columnNames,
updateTable(cmbAdversary.getSelectedItem().toString(),
cmbdataType.getSelectedItem().toString())));
where columnNames is a Vector of Strings
cmbadversary and smbdataType are the selection od combo boxes.
and updateTable is a method that returns a Vector of Vectors depending on the combo box selection as follows:
static Vector updateTable(String FilterVal1 , String FilterVal2)
{
try {
myVector = tssc.testSeverityFunctionService(FilterVal1,FilterVal2);
} catch (Exception e) {
e.printStackTrace();}
return myVector;
}
This is how my custom class MyTableModel that extends AbstractTableModel looks like:
class MyTableModel extends AbstractTableModel
{
Vector columnNames = new Vector();
Vector Fdb = new Vector();
public MyTableModel(Vector cName,Vector rName){
this.columnNames = cName;
this.Fdb = rName;}
public int getColumnCount() { // number of columns in the model.
return columnNames.size();
}
public int getRowCount() { // number of rows in the model.
return Fdb.size();
}
#Override
public String getColumnName(int col) {
return columnNames.get(col).toString();
}
public Object getValueAt(int row, int col) {
Vector v = (Vector) this.Fdb.get(row);
return v.get(col);
}
#Override
public Class getColumnClass(int c) {
Vector v = (Vector) Fdb.get(0);
return v.get(c).getClass();}
public boolean isCellEditable(int row, int col)
{ return true; }
public void setValueAt(Vector value, int row, int col)
{
for(int i=0;i<value.size();i++)
{ for(int j=0;j<columnNames.size();j++) {
Fdb.setElementAt(value.get(j),j); }
}
fireTableCellUpdated(row, col);
}
}
The problem is that when I run the code, the table GUI show me initial values but fails to update when I change the selection in the 2 comboboxes and click the selection button.
The Selection button, btw, calls a method which implements the action listener.
Please help me out. Am no pro in Java, but willing to learn. If you have any followup qs., I'll be happy to provide details.
Your solution seems overly complicated. If I understand the basics, the user chooses a value from a combo box, then based on the selection some data is loaded into the table.
There is no need to create a custom table model to do this.
A TableModel contains data. If you want to change the data, then one way to do this is to simply create a new TableModel. So you add an ActionListener to your combo box. When an item is selected you retrive your data and load the data into an Vector or an Array. Using this data you can create a new TableModel and update the JTable in two lines of code:
DefaultTableModel model = new DefaultTableModel(...);
table.setModel( model );
If you need to customize the model to override the getColumnClass() or isCellEditable() methods, then you should extend the DefaultTableModel. I don't see any need to implement the whole model.
I have a tree and a table on my panel, when I click the tree node, the table needs to change at the same time, but it doesn't. I search online and read the Java tutorial and didn't find any solutions. From some posts I think I need to use fireTableStruetureChanged(), but it just doesn't work in my code. Could anyone help me out of this? The following is the code. Thanks a ton!
public class tableStructureChange extends JFrame implements ... {
.....
/ //columnNames is a public variable, because I need to change the columns later
columnNames = new String[] {"col1","col2"}; */
data = new String[][]{
{"Mary", "Campione"},
{"Alison", "Huml"}, };
table = new JTable(new MyTableModel());
table.setAutoCreateColumnsFromModel( false );
feedback = new JScrollPane(table); //feedback is the bottom panel
...
}
//the following class is the problem, i need the table to be reloaded
//when the class is called, but the table doesn't change at all
public void displayFeedback(String tempString) {
//create table for bottom panel
columnNames = new String[] {"col3","col4", "col5"};
String[][] data = new String[][]{
{"Mary", "Campione", "us"},
{"Alison", "Huml", "canada"}, };
//table = new JTable(data, columnNames);
//fireTableStructureChanged(); //this is the problem part
}
// my table model
class MyTableModel extends AbstractTableModel {
String[] columnNames = new String[] {"col1","col2"};
public int getColumnCount() {
return columnNames.length;
}
public int getRowCount() {
return data.length;
}
public String getColumnName(int col) {
return columnNames[col];
}
public Object getValueAt(int row, int col) {
return data[row][col];
}
}
...
}
In your method displayFeedback you seem to be hoping to replace the JTable object and have the display change to reflect what is selected in the JTree above. Instead of replacing what is in the View object, you should focus your effort on updating the Model, in this case, the AbstractTableModel subclass that you have created. There are a couple ways you can do that, but for a brute force proof of concept, you could do something like the following:
add a constructor to MyTableModel that takes a 2 dimensional array of data
in displayFeedback, create a new instance of MyTableModel that has new data relevant to the tree node that was selected.
call setModel on your global table variable.