java语言中字节码文件的扩展名

A．writeArrayB．writeByteC．writeIntD．writeDouble

A．implementsRunnableB．extendsThreadC．implementsThreadD．extendsRunnable

A．Graphics.drawString()B．repaint()C．paint()D．update()

A．printMessageB．getMessageC．toStringD．fillStackTrace

A．javax.swingB．java.langC．java.utilD．java.applet