The Fake Geek's blog: Next Character

The Fake Geek's blog: Next Character
* Return the smallest character that is strictly larger than the search character, 
* If no such character exists, return the smallest character in the array 
* @param sortedStr : sorted list of letters, sorted in ascending order. 
* @param c : character for which we are searching. 
* Given the following inputs we expect the corresponding output: 
* ['c', 'f', 'j', 'p', 'v'], 'a' => 'c' 
* ['c', 'f', 'j', 'p', 'v'], 'c' => 'f' 
* ['c', 'f', 'j', 'p', 'v'], 'k' => 'p' 
* ['c', 'f', 'j', 'p', 'v'], 'z' => 'c' // The wrap around case 
* ['c', 'f', 'k'], 'f' => 'k' 
* ['c', 'f', 'k'], 'c' => 'f' 
* ['c', 'f', 'k'], 'd' => 'f' 
The problem doesn't clarify if duplicates are allowed in the array. So I wrote two.

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public class SmallestCharacter {  public char nextChar(char[] list, char c) {   if (list == null || list.length == 0)    throw new IllegalArgumentException("Null or empty list!");   int start = 0;   int end = list.length - 1;   if (c < list[0] || c >= list[list.length - 1])    return list[0];   while (start < end) {    int mid = (start + end) / 2;    if (c == list[mid]) {     //System.out.println(mid + ": " + list[mid]);     return list[mid + 1];    }    else if (c < list[mid]) {     //System.out.println("smaller: " + mid);     end = mid - 1;    }    else {     //System.out.println("greater: " + mid);     start = mid + 1;    }   }   if (list[start] == c)    return list[start + 1];   return list[start];  } }

Duplicates are allowed (not much difference though...)

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public char nextChar2(char[] list, char c) {   if (list == null || list.length == 0)    throw new IllegalArgumentException("Null or empty list!");   int start = 0;   int end = list.length - 1;   if (c < list[0] || c >= list[list.length - 1])    return list[0];   while (start < end) {    int mid = (start + end) / 2;    if (c == list[mid]) {     if (list[mid + 1] > c)      return list[mid + 1];     else      start = mid + 1;    }    else if (c < list[mid]) {     end = mid - 1;    }    else     start = mid + 1;   }   if (list[start] == c)    return list[start + 1];   return list[start];  }

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