Find All Anagrams in a String LeetCode solution in Java

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class Solution {
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  public List<Integer> findAnagrams(String s, String p) {
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    int fullMatchCount = p.length();
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    Map<Character, Integer> anagramMap = new HashMap<>();
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    for (Character c : p.toCharArray()) anagramMap.put(c, anagramMap.getOrDefault(c, 0) + 1);
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    List<Integer> result = new ArrayList<>();
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    int left = 0, right = 0, currentMatchCount = 0;
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    Map<Character, Integer> currentAnagramMap = new HashMap<>();
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    while (right < s.length()) {
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      char c = s.charAt(right);
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      if (anagramMap.get(c) == null) {
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        currentAnagramMap = new HashMap<>();
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        right++;
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        left = right;
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        currentMatchCount = 0;
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        continue;
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      }
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      currentAnagramMap.put(c, currentAnagramMap.getOrDefault(c, 0) + 1);
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      currentMatchCount++;
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      if (currentAnagramMap.get(c) > anagramMap.get(c)) {
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        char leftC = s.charAt(left);
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        while (leftC != c) {
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          currentAnagramMap.put(leftC, currentAnagramMap.get(leftC) - 1);
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          left++;
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          leftC = s.charAt(left);
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          currentMatchCount--;
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        }
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        left++;
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        currentAnagramMap.put(c, currentAnagramMap.get(c) - 1);
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        currentMatchCount--;
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      }
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      if (currentMatchCount == fullMatchCount) result.add(left);
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      right++;
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    }
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    return result;
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  }
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}