如何使用信息摘要？(100分)

如下所示，是一段信息摘要的加密，源自JDK文档，请问如何读出
byte[] toChapter1Digest = tc1.digest;
的加密结果，是读byte值吗，需要定义一个字符串吗，谁能给我一个例子程序，谢谢。
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MessageDigest md = MessageDigest.getInstance("SHA");
try {
md.update(toChapter1);
MessageDigest tc1 = md.clone();
byte[] toChapter1Digest = tc1.digest;
md.update(toChapter2);
...etc.
} catch (CloneNotSupportedException cnse) {
throw new DigestException("couldn't make digest of partial content");
}

就是读字节数组，上面的例子就是：toChapter1Digest

消息摘要的结果就是一串字节码
MessageDigest md = MessageDigest.getInstance("SHA");
//产生SHA算法的MessageDigest
try {
md.update(toChapter1);
//change digest using toChapter1
MessageDigest tc1 = md.clone();
byte[] toChapter1Digest = tc1.digest;
//compute hash and pad array of byte
md.update(toChapter2);
...etc.
} catch (CloneNotSupportedException cnse) {
throw new DigestException("couldn't make digest of partial content");
}

消息摘要的读出是字节码，你可以把它转化为BASE64编码方式或者16进制都可以