如何检查JTable JAVA中是否存在行？

Question

I searched but there are no similar questions.

I have a function with 2 parameters: row_num, value Before adding a new value, I need to check to see if that row exists in the JTable or not. If it is not, I will add a null row before adding value.

The problem is I don't know how to check if it exists. I tried table.isCellEditable(row_num, 2) but I'm not sure why it always returns True though the table doesn't contain that row.

Answer 1

There's not much to go on here. Just check the table row count:

DefaultTableModel dtm = (DefaultTableModel) yourTable.getModel();
int rows = dtm.getRowCount();

If the value in row_num is greater than rows then the row obviously doesn't exist yet. If row_num is working off of the JTable index value which is 0 based then you would need to subtract 1 from rows or:

if (row_num < rows) { 
    System.out.println("Yup...The row number " + row_num + " does exist!");
    // Call your specific method here....
}

Or is it that you are trying to compare a value contained within a row specific row cell in which case we would also need the column number of that specific cell. Maybe I'm just not grasping your question properly and I have this all wrong in which case I'll simply delete this answer.