JAVA base64

需先反射jdk中不公开的类

public static String encodeBase64(byte[] input) throws Exception {      Class clazz = Class.forName("com.sun.org.apache.xerces.internal.impl.dv.util.Base64");      Method mainMethod = clazz.getMethod("encode", byte[].class);      mainMethod.setAccessible(true);      Object retObj = mainMethod.invoke(null, new Object[] { input });      return (String) retObj;   }   /***    * decode by Base64    */   public static byte[] decodeBase64(String input) throws Exception {      Class clazz = Class.forName("com.sun.org.apache.xerces.internal.impl.dv.util.Base64");      Method mainMethod = clazz.getMethod("decode", String.class);      mainMethod.setAccessible(true);      Object retObj = mainMethod.invoke(null, input);      return (byte[]) retObj;   }