在jTabbedPane中向jTextarea添加文本

I have a desktop program with 3 tabs i'm building in netbeans. There is 1 text input field below the three tabs. each tab has a jtextarea component. When i type in the text input field and hit enter i want it to add that text to the textarea contained by the currently selected tab.I have a desktop program with 3 tabs i'm buildi