JFileChooser

String arquivo = "";
		
		JFileChooser fc = new JFileChooser();
		fc.setDialogTitle("Abrir");
			
		if (fc.showOpenDialog(this) == JFileChooser.APPROVE_OPTION)
		{
			arquivo = fc.getSelectedFile().getPath();

			File f = new File(arquivo);

			if (f.exists()) 
			{

				try
				{
					Reader in = new FileReader(f);
					char[] buff = new char[4096];
					int nch;
					while ((nch = in.read(buff, 0, buff.length)) != -1) 
					{					
						ta.append(new String(buff, 0, nch));
					}
				}
				catch(Exception e)
				{
					e.printStackTrace();
				}
			}
		}