Setting the Width of a Column in a JTable Component
By default, the column widths of all columns are equal. In order for
column width adjustments to be made, autoResizeMode must be
disabled.
int rows = 3;
int cols = 3;
JTable table = new JTable(rows, cols);
// Disable auto resizing
table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
// Set the first visible column to 100 pixels wide
int vColIndex = 0;
TableColumn col = table.getColumnModel().getColumn(vColIndex);
int width = 100;
col.setPreferredWidth(width);
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