Character with Longest Consecutive Repetition in Java

The challenge

For a given string s find the character c (or C) with longest consecutive repetition and return:

Object[]{c, l};

where l (or L) is the length of the repetition. If there are two or more characters with the same l return the first in order of appearance.

For empty string return:

Object[]{"", 0}

Test cases

import org.junit.Test;
import static org.junit.Assert.assertArrayEquals;
import org.junit.runners.JUnit4;

public class SolutionTest {
    @Test
    public void exampleTests() {
        assertArrayEquals(new Object[]{"a", 4}, Solution.longestRepetition("aaaabb"));
        assertArrayEquals(new Object[]{"a", 4}, Solution.longestRepetition("bbbaaabaaaa"));
        assertArrayEquals(new Object[]{"u", 3}, Solution.longestRepetition("cbdeuuu900"));
        assertArrayEquals(new Object[]{"b", 5}, Solution.longestRepetition("abbbbb"));
        assertArrayEquals(new Object[]{"a", 2}, Solution.longestRepetition("aabb"));
        assertArrayEquals(new Object[]{"", 0}, Solution.longestRepetition(""));
    }
}

The solution in java

Option 1:

public class Solution {
    public static Object[] longestRepetition(String s) {
        
        int len = s.length(); 
        int count = 0; 
      
        if (len==0) return new Object[]{"", 0};
  
        char res = s.charAt(0); 
        for (int i=0; i<len; i++) { 
            int cur_count = 1; 
            for (int j=i+1; j<len; j++) { 
                if (s.charAt(i) != s.charAt(j)) break; 
                cur_count++; 
            } 
  
            if (cur_count > count) { 
                count = cur_count; 
                res = s.charAt(i); 
            } 
        } 
      
        return new Object[]{Character.toString(res), count};
    }
}

Option 2:

public class Solution {
  
  public static Object[] longestRepetition(String s) {
    char lastch = '\0';
    Object ret[] = new Object[]{"", 0};
    int n = 0, max = 0;
    for (char c : s.toCharArray()) {
      n = lastch == c ? ++n : 1;
      if (n > max) { ret = new Object[]{""+c,n}; max = n; }
      lastch = c;
    }
    return ret;
  }

}
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