[ISSUE #2618]modify config service md5 generation method

[wangweizZZ]

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What is the purpose of the change

#2618

Brief changelog

modify com.alibaba.nacos.common.utils.Md5Utils
use org.apache.commons.codec generate md5 string

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[chuntaojun]

Just unify the MD5 generation on both sides using the same utility class

[chuntaojun]

Drop the MD5 utility classes into the common module

[chuntaojun]

The utility class is already at the end of Utils

[wangweizZZ]

sorry,I don't understand what you mean. the utility class is move from client module to common module. do you mean name should like MD5Utils end with Utils?

[chuntaojun]

yes

[chuntaojun]

It looks like this dependency is not used, so it can be removed

[wangweizZZ]

yes, i agree

[chuntaojun]

I think the MD5 implementation will not be as good as the MD5Utils you delete because of the locking mechanism, you can only modify the string method of MD5Utils

old

return new BigInteger(1, messageDigest.digest(bytes)).toString(HEX_VALUE_COUNT);

new

public String bytes2string(byte[] bt) {
        int l = bt.length;

        char[] out = new char[l << 1];

        for (int i = 0, j = 0; i < l; i++) {
            out[j++] = digits[(0xF0 & bt[i]) >>> 4];
            out[j++] = digits[0x0F & bt[i]];
        }

        return new String(out);
    }

[wangweizZZ]

Thanks for your patient.I choose this one ,consider MessageDigest classes is instantiated only once.