Repair the interface and Read POO

Today i check the inerface, and see some problems with the Jtable. The first, the table was editable, then i investagate and use the function .setEnabled(false);. The other problem was that i will drag and drop the column then i use this other function .getTableHeader().setReorderingAllowed(false);. Other problem with the interface was the use of .setPreferredScrollableViewportSize(); because this not complement the panel then i prefer use .setFillsViewportHeight(true);. The last problem that went to my mind, was how i can add a new row?. At the begining i try to find a function that said like a .addRow, but after the investigate i discover that i need create a new model table model said DefaultTableModel, this said that the table can has other models but i prefferd the model that i has. When i try to upload my proyect to bitBucked i see that in my computer have  many branches useless. Then  i try delete all and rename 1 for add the interface, but isnt works. The rest of the day i read the Intro to Object Orientation. This blog was a little summary of my university POO