To remove a row of data from a JTable component, you need to remove it from its table model. A simple implementation of a table model that supports the removal of row data is DefaultTableModel. 
When removing a row using DefaultTableModel.removeRow(), the index of the row must be specified. Row indices start from 0. For example, if there are 2 rows in a table, the index of the first row is 0 and the index of the second row is 1. Removing a row at index 0 removes the first row. 

    DefaultTableModel model = new DefaultTableModel();
    JTable table = new JTable(model);
    
    // Create some data
    model.addColumn("Col1");
    model.addRow(new Object[]{"r1"});
    model.addRow(new Object[]{"r2"});
    model.addRow(new Object[]{"r3"});
    
    // Remove the first row
    model.removeRow(0);
    
    // Remove the last row
    model.removeRow(model.getRowCount()-1);