Jython：Java的Python

来源： 作者： 时间：2007-08-08 点击：

, '/' ]

keys = swing.JPanel(awt.GridLayout(4, 4))      # do Java class library magic
display = swing.JTextField( )                  # Python data auto-mapped to Java

def push(event):                                # callback for regular keys
    display.replaceSelection(event.actionCommand)

def enter(event):                             # callback for the '=' key
    display.text = str(eval(display.text))    # use Python eval( ) to run expr
    display.selectAll( )

for label in labels:                          # build up button widget grid
    key = swing.JButton(label)                # on press, invoke Python funcs
    if label == '=':
        key.actionPerformed = enter
    else:
        key.actionPerformed = push
    keys.add(key)

panel = swing.JPanel(awt.BorderLayout( ))      # make a swing panel
panel.add("North", display)                     # text plus key grid in middle
panel.add("Center", keys)
swing.test(panel)                               # start in a GUI viewer

The first thing you should notice is that this is genuine Python codeJython scripts use the same core language that we've been using all along in this book. That's good news, both because Python is such an easy language to use and because you don't need to learn a new, proprietary scripting language to use Jython. It also means that all of Python's high-level language syntax and tools are available. For example, in this script, the Python