关于抽象方法Toolkit.getScreenSize()的困惑
以下程序片段用于获取当前屏幕尺寸：
Toolkit kit=new Toolkit.getDefaultToolkit();
Dimension screenSize=kit.getScreenSize();

请教各位大虾，getScreenSize()是抽象方法，并没有定义功能，怎么还可以调用？这里是不是调用了Toolkit的子类中覆写的getScreenSize()？如果是的话，这里的子类是哪个？
------解决方案--------------------
下面是kit.getScreenSize()方法的实现

public static synchronized Toolkit getDefaultToolkit() {

        if (toolkit == null) {

            try {

                // We disable the JIT during toolkit initialization.  This

                // tends to touch lots of classes that aren't needed again

                // later and therefore JITing is counter-productiive.

                java.lang.Compiler.disable();

                

                java.security.AccessController.doPrivileged(

                        new java.security.PrivilegedAction() {

                    public Object run() {

                        String nm = null;

                        Class cls = null;

                        try {

                            nm = System.getProperty("awt.toolkit", "sun.awt.X11.XToolkit");

                            try {

                                cls = Class.forName(nm);

                            } catch (ClassNotFoundException e) {

                                ClassLoader cl = ClassLoader.getSystemClassLoader();

                                if (cl != null) {

                                    try {

                                        cls = cl.loadClass(nm);

                                    } catch (ClassNotFoundException ee) {

                                        throw new AWTError("Toolkit not found: " + nm);

                                    }