Latest Time by Replacing Hidden Digits LeetCode solution in Java

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class Solution {
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  public String maximumTime(String time) {
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    char[] times = time.toCharArray();
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    // for times[0]
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    // if both characters of hour is ?, then hour is 23 then times[0] should be '2'("??:3?)".
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    // if 2nd character of hour is <= 3, then hour can be in 20s  then times[0] should be '2'.
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    // if 2nd character of hour is >3, then hour can only be in 10s  then times[0] should be '1'.
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    if (times[0] == '?') times[0] = (times[1] <= '3' || times[1] == '?') ? '2' : '1';
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    // if 1st character of hour is 0 or 1, then hour can be 09 or 19 then times[1] should be '9'.
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    // if 1st character of hour is 2, then hour can be 23 then times[1] should be '3'.
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    if (times[1] == '?') times[1] = times[0] == '2' ? '3' : '9';
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    // if both characters of minute is ? then minute is 59, or only 4th character is ? then 5_ so
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    // times[3] is always '5'.
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    if (times[3] == '?') times[3] = '5';
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    // if 2nd character of minute is ?, then times[4] is '9'.
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    if (times[4] == '?') times[4] = '9';
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    return new String(times);
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  }
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}