java 在java中解码md5加密
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decode md5 ecnrytion in java
提问by
public static String convertToMD5(String input) throws Exception {
String md5 = null;
if (null == input)
return null;
try {
// Create MessageDigest object for MD5
MessageDigest digest = MessageDigest.getInstance("MD5");
// Update input string in message digest
digest.update(input.getBytes(), 0, input.length());
// Converts message digest value in base 16 (hex)
md5 = new BigInteger(1, digest.digest()).toString(16);
} catch (NoSuchAlgorithmException e) {
throw e;
}
return md5;
}
using this code to encrypt the string i want to decode md5 encryption to normal string? can you help
使用此代码加密字符串我想将 md5 加密解码为普通字符串？你能帮我吗
采纳答案by px06
To add onto @dit's answer, you only have one option; which is to compare MD5 strings, for example. MD5("cat") == MD5("cat"), there is no way to derive "cat"from MD5("cat")because as explained it's a hash function.
要添加@dit 的答案，您只有一种选择；例如，这是比较 MD5 字符串。MD5("cat") == MD5("cat")，没有办法推导"cat"出来，MD5("cat")因为正如解释的那样，它是一个散列函数。
Here is something you can use for comparison:
您可以使用以下内容进行比较：
public static boolean matching(String orig, String compare){
String md5 = null;
try{
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(compare.getBytes());
byte[] digest = md.digest();
md5 = new BigInteger(1, digest()).toString(16);
return md5.equals(orig);
} catch (NoSuchAlgorithmException e) {
return false;
}
return false;
}
Then you can call matching("d077f244def8a70e5ea758bd8352fcd8", "cat");which will return true, and if matching(MD5("x"), "y")it will return false.
然后你可以调用matching("d077f244def8a70e5ea758bd8352fcd8", "cat");which will return true，如果matching(MD5("x"), "y")它会返回 false 。
回答by dieter
md5 is not a encryption algorithm. It is a hash function. The hashed string can not be decoded. The original string is "destroyed" / hashed forever.
md5 不是加密算法。它是一个散列函数。散列字符串无法解码。原始字符串被“销毁”/永远散列。
