Question

I have a table model. I want to delete a row from a table. I am not able to find the model.removeRow method. Can someone tell he how to remove a row? Below is the code for the model.

class TableModel extends AbstractTableModel {
private Object[][] data;
private String[] columnNames;

public TableModel(Object[][] data) {
    this.data = data;
    columnNames=new String[1];
    columnNames[0]="Data";
}

public int getRowCount() {
    return data.length;
}

public int getColumnCount() {
    return columnNames.length;
}

public Object getValueAt(int rowIndex, int columnIndex) {
    return data[rowIndex][columnIndex];
}

public Class getColumnClass(int c) {
    return String.class;
}

public boolean isCellEditable(int rowIndes, int columnIndex) {
    return false;
}

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

public void setValueAt(Object value, int rowIndex, int columnIndex) {
    data[rowIndex][columnIndex] = value;
    fireTableCellUpdated(rowIndex, columnIndex);
}

}

Answer 1

Kaushik, if you really want to make your own implementation of the TableModel interface and deal with the storage of rows manually (as you obviously do by using Object[][] data), then you must implement the removeRow() method because abstract table model does not “know” how to do it. removeRow() will have to fireTableRowsDeleted() at the end…

A good alternative is to refactor your class and make it extend the DefaultTableModel.

Another suggestion – since table model changes a lot, a dynamic array may be a bad choice for storage because you must either reallocate space every time you add a row (bad), or you preallocate enough space for certain number of rows, then whenever there is no enough space you allocate new Object[][] with some extra space (for next N rows). Typically people allocate enough space for 2^n rows during the reallocation process.