set column-width in a JTable
javax.swing.table.JTable
JTable table = new JTable(10, 20); // turn off autoresizing, or else all columns are equal wide: table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF); // set first column on 100 pixel width: final int INDEX_COLUMN1 = 0; TableColumn col = table.getColumnModel().getColumn(INDEX_COLUMN1); col.setPreferredWidth(100);