Java实现敏感词过滤工具与方法

class TrieNode {
    Map children = new HashMap();
    boolean isEnd = false;
    String replacement = "*";
}
class SensitiveFilter {
private final TrieNode root = new TrieNode();
public void addWord(String word) {
    TrieNode node = root;
    for (char c : word.toCharArray()) {
        node.children.computeIfAbsent(c, k -> new TrieNode());
        node = node.children.get(c);
    }
    node.isEnd = true;
    node.replacement = "*".repeat(word.length()); // 或自定义
}

public String filter(String text) {
    StringBuilder result = new StringBuilder();
    for (int i = 0; i < text.length(); i++) {
        int matchLen = searchLongest(text, i); // 从i开始最长匹配长度
        if (matchLen > 0) {
            result.append(root.children.get(text.charAt(i)).replacement);
            i += matchLen - 1;
        } else {
            result.append(text.charAt(i));
        }
    }
    return result.toString();
}

private int searchLongest(String s, int start) {
    TrieNode node = root;
    int len = 0;
    for (int i = start; i < s.length(); i++) {
        char c = s.charAt(i);
        if (!node.children.containsKey(c)) break;
        node = node.children.get(c);
        len++;
        if (node.isEnd) return len; // 找到最短有效词即返回（可改为记录最长）
    }
    return 0;
}
}