简易的DFS算法敏感词过滤方法

• SensitiveWordInit
• SensitivewordEngine

---

public class SensitiveWordInit
{
    /**
     * 敏感词库
     */
    public HashMap sensitiveWordMap;

    /**
     * 初始化敏感词
     *
     * @return
     */
    public Map initKeyWord(List sensitiveWords)
    {
        try
        {
            // 从敏感词集合对象中取出敏感词并封装到Set集合中
            Set keyWordSet = new HashSet();
            for (String s : sensitiveWords)
            {
                keyWordSet.add(s.trim());
            }
            // 将敏感词库加入到HashMap中
            addSensitiveWordToHashMap(keyWordSet);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        return sensitiveWordMap;
    }

    /**
     * 封装敏感词库
     *
     * @param keyWordSet
     */
    @SuppressWarnings("rawtypes")
    private void addSensitiveWordToHashMap(Set keyWordSet)
    {
        // 初始化HashMap对象并控制容器的大小
        sensitiveWordMap = new HashMap(keyWordSet.size());
        // 敏感词
        String key = null;
        // 用来按照相应的格式保存敏感词库数据
        Map nowMap = null;
        // 用来辅助构建敏感词库
        Map newWorMap = null;
        // 使用一个迭代器来循环敏感词集合
        Iterator iterator = keyWordSet.iterator();
        while (iterator.hasNext())
        {
            key = iterator.next();
            // 等于敏感词库，HashMap对象在内存中占用的是同一个地址，所以此nowMap对象的变化，sensitiveWordMap对象也会跟着改变
            nowMap = sensitiveWordMap;
            for (int i = 0; i < key.length(); i++)
            {
                // 截取敏感词当中的字，在敏感词库中字为HashMap对象的Key键值
                char keyChar = key.charAt(i);

                // 判断这个字是否存在于敏感词库中
                Object wordMap = nowMap.get(keyChar);
                if (wordMap != null)
                {
                    nowMap = (Map) wordMap;
                }
                else
                {
                    newWorMap = new HashMap();
                    newWorMap.put("isEnd", "0");
                    nowMap.put(keyChar, newWorMap);
                    // nowMap指向newWorMap（关键！）
                    nowMap = newWorMap;
                }

                // 如果该字是当前敏感词的最后一个字，则标识为结尾字
                if (i == key.length() - 1)
                {
                    nowMap.put("isEnd", "1");
                }
                System.out.println("封装敏感词库过程："+sensitiveWordMap);
            }
            System.out.println("查看敏感词库数据:" + sensitiveWordMap);
        }
    }
}

public class SensitivewordEngine
{
    /**
     * 敏感词库
     */
    public static Map sensitiveWordMap = null;

    /**
     * 只过滤最小敏感词
     */
    public static int minMatchTYpe = 1;

    /**
     * 过滤所有敏感词
     */
    public static int maxMatchType = 2;

    /**
     * 敏感词库敏感词数量
     *
     * @return
     */
    public static int getWordSize()
    {
        if (SensitivewordEngine.sensitiveWordMap == null)
        {
            return 0;
        }
        return SensitivewordEngine.sensitiveWordMap.size();
    }

    /**
     * 是否包含敏感词
     *
     * @param txt
     * @param matchType
     * @return
     */
    public static boolean isContaintSensitiveWord(String txt, int matchType)
    {
        boolean flag = false;
        for (int i = 0; i < txt.length(); i++)
        {
            int matchFlag = checkSensitiveWord(txt, i, matchType);
            if (matchFlag > 0)
            {
                flag = true;
            }
        }
        return flag;
    }

    /**
     * 获取敏感词内容
     *
     * @param txt
     * @param matchType
     * @return 敏感词内容
     */
    public static Set getSensitiveWord(String txt, int matchType)
    {
        Set sensitiveWordList = new HashSet();

        for (int i = 0; i < txt.length(); i++)
        {
            int length = checkSensitiveWord(txt, i, matchType);
            if (length > 0)
            {
                // 将检测出的敏感词保存到集合中
                sensitiveWordList.add(txt.substring(i, i + length));
                i = i + length - 1;
            }
        }

        return sensitiveWordList;
    }

    /**
     * 替换敏感词
     *
     * @param txt
     * @param matchType
     * @param replaceChar
     * @return
     */
    public static String replaceSensitiveWord(String txt, int matchType, String replaceChar)
    {
        String resultTxt = txt;
        Set set = getSensitiveWord(txt, matchType);
        Iterator iterator = set.iterator();
        String word = null;
        String replaceString = null;
        while (iterator.hasNext())
        {
            word = iterator.next();
            replaceString = getReplaceChars(replaceChar, word.length());
            resultTxt = resultTxt.replaceAll(word, replaceString);
        }

        return resultTxt;
    }

    /**
     * 替换敏感词内容
     *
     * @param replaceChar
     * @param length
     * @return
     */
    private static String getReplaceChars(String replaceChar, int length)
    {
        String resultReplace = replaceChar;
        for (int i = 1; i < length; i++)
        {
            resultReplace += replaceChar;
        }

        return resultReplace;
    }

    /**
     * 检查敏感词数量
     *
     * @param txt
     * @param beginIndex
     * @param matchType
     * @return
     */
    public static int checkSensitiveWord(String txt, int beginIndex, int matchType)
    {
        boolean flag = false;
        // 记录敏感词数量
        int matchFlag = 0;
        char word = 0;
        Map nowMap = SensitivewordEngine.sensitiveWordMap;
        for (int i = beginIndex; i < txt.length(); i++)
        {
            word = txt.charAt(i);
            // 判断该字是否存在于敏感词库中
            nowMap = (Map) nowMap.get(word);
            if (nowMap != null)
            {
                matchFlag++;
                // 判断是否是敏感词的结尾字，如果是结尾字则判断是否继续检测
                if ("1".equals(nowMap.get("isEnd")))
                {
                    flag = true;
                    // 判断过滤类型，如果是小过滤则跳出循环，否则继续循环
                    if (SensitivewordEngine.minMatchTYpe == matchType)
                    {
                        break;
                    }
                }
            }
            else
            {
                break;
            }
        }
        if (!flag)
        {
            matchFlag = 0;
        }
        return matchFlag;
    }

    public static void main(String[] args){
        List sensitiveWords = new ArrayList<>();
        sensitiveWords.add("王八");
        sensitiveWords.add("王八蛋");
        sensitiveWords.add("王八羔子");
        sensitiveWords.add("黄网");
        sensitiveWords.add("图片");

        sensitiveWordMap = new SensitiveWordInit().initKeyWord(sensitiveWords);

        System.out.println(isContaintSensitiveWord("艹尼玛",1));
        System.out.println(replaceSensitiveWord("你个王八羔子哦",1,"*"));
        System.out.println(replaceSensitiveWord("你个王八羔子哦",2,"*"));
    }