Getting column names from an AbstractTableModel

Question

I can't figure out something using the constructor JTable(TableModel dm).

I'm using a LinkedList to manage my data so, to display it, I extended AbstractTableModel:

public class VolumeListTableModel extends AbstractTableModel {

    private static final long serialVersionUID = 1L;
    private LinkedList<Directory> datalist;
    private Object[] columnNames= {"ID", "Directory", "Wildcard"};


    public VolumeListTableModel(){
    }

    public void setDatalist(LinkedList<Directory> temp){
        this.datalist = temp;
    }

    public LinkedList<Directory> getDatalist(){
        return (LinkedList<Directory>) this.datalist.clone();
    }

    public Object[] getColumnNames() {
        return this.columnNames;    
    }

    @Override
    public int getColumnCount() {
        return Directory.numCols;
    }

    @Override
    public int getRowCount() {
        return this.datalist.size();
    }

    @Override
    public Object getValueAt(int row, int col) {

        Directory temp = this.datalist.get(row);

        switch(col){
        case 0:
            return temp.getId();
        case 1:
            return temp.getPath();
        case 2:
            return temp.getWildcard();
        default:
            return null;        
        }
    }

I'm doing something wrong because when I run my GUI I get column names labeled A,*B*,C.

score 15 · Accepted Answer · answered Nov 16 '10 at 10:10

15

There is no method in AbstractTableModel called getColumnNames, so I believe your method is being ignored. The actual method you want to override is the getColumnName method.

Try adding this method to your VolumeListTableModel class

public String getColumnName(int column) {
    return columnNames[column];
}

answered Nov 16 '10 at 10:10

Codemwnci

54,176
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1

Thank you everybody. I'm giving the answer to Codemwnci due to the response time. – dierre Nov 16 '10 at 10:23

score 4 · Answer 2 · edited Oct 04 '12 at 10:25

4

You need to override the getColumnName method which in your case will simply

return columnNames[column];

edited Oct 04 '12 at 10:25

Ben

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answered Nov 16 '10 at 10:12

Jim

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score 3 · Answer 3 · answered Nov 16 '10 at 10:15

3

You have to Override this method :

public String getColumnName(int column)

answered Nov 16 '10 at 10:15

jruillier

365
4
16

Luca Fagioli · Answer 4 · 2013-06-14T08:55:03.253

AbstractTableModel does not have a getColumnNames method, but it is easy to implement:

public class VolumeListTableModel extends AbstractTableModel {

    // [...]

    public String[] getColumnNames() {

        String[] columnNames = new String[this.getColumnCount()];

        for (int i = 0, columnCount = this.getColumnCount(); i < columnCount; i++) {    
            columnNames[i] = this.getColumnName(i);
        }

        return columnNames;

    }

    // [...]

}

Getting column names from an AbstractTableModel

4 Answers4