As Fredrik mentions in his answer, the simple way to achieve this is to place the JTextArea in a JScrollPane. This will allow scrolling of the view area of the JTextArea.
Just for the sake of completeness, the following is how it could be achieved:
JTextArea ta = new JTextArea();
JScrollPane sp = new JScrollPane(ta); // JTextArea is placed in a JScrollPane.
Once the JTextArea is included in the JScrollPane, the JScrollPane should be added to where the text area should be. In the following example, the text area with the scroll bars is added to a JFrame:
JFrame f = new JFrame();
f.getContentPane().add(sp);
Thank you kd304 for mentioning in the comments that one should add the JScrollPane to the container rather than the JTextArea — I feel it’s a common error to add the text area itself to the destination container rather than the scroll pane with text area.
The following articles from The Java Tutorials has more details:
- How to Use Scroll Panes
- How to Use Text Areas