sun内部使用的那些东西
sun.misc.Unsafe这个类与并发相关的，提供了硬件上面的原子操作，以及一些其他的功能如：绕过所有的东西，实例化任意类的对象等等，反正Unsafe这个类很重要。
sun.reflect.ReflectionFactory：反射那块使用。
sun.misc.ProxyGenerator： 生成代理类。
public static byte[] generateProxyClass(final String name,
320 Class[] interfaces)
321 {
322 ProxyGenerator gen = new ProxyGenerator(name, interfaces);
323 final byte[] classFile = gen.generateClassFile();
324
325 if (saveGeneratedFiles) {
326 java.security.AccessController.doPrivileged(
327 new java.security.PrivilegedAction() {
328 public Object run() {
329 try {
330 FileOutputStream file =
331 new FileOutputStream(dotToSlash(name) + ".class");
332 file.write(classFile);
333 file.close();
334 return null;
335 } catch (IOException e) {
336 throw new InternalError(
337 "I/O exception saving generated file: " + e);
338 }
339 }
340 });
341 }
342
343 return classFile;
344 }
sun.misc.Launcher这个类与classloader相关的。看看下面代码：
/**
246 * The class loader used for loading from java.class.path.
247 * runs in a restricted security context.
248 */
249 static class AppClassLoader extends URLClassLoader {
250
251 public static ClassLoader getAppClassLoader(final ClassLoader extcl)
252 throws IOException
253 {
254 final String s = System.getProperty("java.class.path");
255 final File[] path = (s == null) ? new File[0] : getClassPath(s);
256
257 // Note: on bugid 4256530
258 // Prior implementations of this doPrivileged() block supplied
259 // a rather restrictive ACC via a call to the private method
260 // AppClassLoader.getContext(). This proved overly restrictive
261 // when loading classes. Specifically it prevent
262 // accessClassInPackage.sun.* grants from being honored.
263 //
264 return (AppClassLoader)
265 AccessController.doPrivileged(new PrivilegedAction() {
266 public Object run() {
267 URL[] urls =
268 (s == null) ? new URL[0] : pathToURLs(path);
269 return new AppClassLoader(urls, extcl);
270 }
271 });
272 }
273
274 /*
275 * Creates a new AppClassLoader
276 */
277 AppClassLoader(URL[] urls, ClassLoader parent) {
278 super(urls, parent, factory);
279 }
280
http://hg.openjdk.java.net/jdk6/jdk6/jdk/file/tip/src/share/classes/sun/