Set order of columns in JTable

I have a JTable with some columns. I have a HashMap of the column identifier mapped to the position in the view, for example:

TableHeader1 | TableHeader2 | TableHeader3
    sth.           sth.          sth.

I know that:

TableHeader1 -> position 0
TableHeader2 -> position 1
TableHeader3 -> position 2

Now I want to reorder the columns. I know that there is a function called moveColumn(A, B) within the JTable class. This moves a column from A to B, and B is putted left or right. My problem is, I want to order the whole table in a specific way, how can I do this? If I use moveColumn, I cannot know where B has been moved,开发者_运维百科 in 5 out of 10 cases it might be the right side and in the other cases the wrong side.

Hope you understand my problem :-)

You can change the columns order by removing all of them and adding them in the right order:

public static void setColumnOrder(int[] indices, TableColumnModel columnModel) {
    TableColumn column[] = new TableColumn[indices.length];

    for (int i = 0; i < column.length; i++) {
        column[i] = columnModel.getColumn(indices[i]);
    }

    while (columnModel.getColumnCount() > 0) {
        columnModel.removeColumn(columnModel.getColumn(0));
    }

    for (int i = 0; i < column.length; i++) {
        columnModel.addColumn(column[i]);
    }
}

OK how about this. Might be a bit left field.

Extend TableColumn and give your new class a position property. Have it implement Comparable and use the position to compare columns.

Next, extend DefaultTableColumnModel and store TableColumns in an ordered list.

Your JTable should now display columns according to their position. Untested but it sounds interesting so I might give it a go later.

Based on @Guillaume answer I found a way to do that without the need to remove all columns and add them again.

  public static void setColumnOrder(int[] indices, JTable table, TableColumnModel columnModel) {

    for (int i = 0; i < indices.length; i++) {
      columnModel.moveColumn(i, table.convertColumnIndexToView(indices[i]));
    }
  }

This works better for me because with (SwingX) JXTable, the order of the invisible columns is not modified.

If you want to reorder by column name then you can check out the Table Column Reordering suggestion.

This problem can be solved by using the built in moveColumn function as a bubble sort shortcut. The hashmap holds your weights in that case. Keep in mind that getColumnModel().getColumn(j).getModelIndex() can be seen as the initial column index / ID that will not change. See it as a column title.

HashMap<int, int> mapOrder = new HashMap<int, int>();

for (int i = 0; i < jt_table.getColumnCount(); i++) {
    for (int j = 0; j < jt_table.getColumnCount() - 1; j++) {
        int col1 = mapOrder.get(jt_table.getColumnModel().getColumn(j).getModelIndex());
        int col2 = mapOrder.get(jt_table.getColumnModel().getColumn(j + 1).getModelIndex());
        if (col1 > col2) {
            jt_table.moveColumn(jt_table.getColumnModel().getColumn(j).getModelIndex(), jt_table.getColumnModel().getColumn(j + 1).getModelIndex());
        }
    }
}