Automatically scroll to the bottom of a text area

Question

I have a text area with scroll bar. At regular intervals, I am adding new lines of text to it. I would like the text area to automatically scroll to the bottom-most entry (the newest one) whenever a new line is added. How can I accomplish this?

textAreaStatus = new WebTextArea();
scrollPane = new JScrollPane(textAreaStatus);
textAreaStatus.setBackground(Color.black);
textAreaStatus.setBorder(BorderFactory.createEmptyBorder(4, 4, 4, 4));

Solution 1

Have a look at the updatePolicy property of DefaultCaret: it might do what you want

DefaultCaret caret = (DefaultCaret) textArea.getCaret();
caret.setUpdatePolicy(ALWAYS_UPDATE);

A nice summary of options by Rob (@camickr)

Solution 2

textArea.setCaretPosition(textArea.getDocument().getLength());

Comments

[itro]

Every time that i add text to taxArea should i call textArea.setCaretPosition(textArea.getDocument().getLength()‌​); ? Is there any other way to do it automatically? Is there any listener for textArea to use?

[itro]

I get erro in IDE and i put DefaultCaret. to ALWAYS_UPDATE like caret.setUpdatePolicy(DefaultCaret.ALWAYS_UPDATE); where should i put this code? when should i call the code that you provideded and where?

[kleopatra]

@user3764804 rolled back the edit as it was not necessary - static imports do the magic ;-)

[Sh4d0wsPlyr]

@itro - Why not add a function to add text. For example, I have a function to add text to my text area. Simple matter of adding an extra line to my function to update it automatically.