敏感字过滤java

傷城~ 2023-07-10 15:43 32阅读 0赞

直接上代码：

import java.util.HashSet;
    import java.util.Iterator;
    import java.util.Map;
    import java.util.Set;
    //敏感词过滤器：利用DFA算法  进行敏感词过滤
    @SuppressWarnings("rawtypes")
    public class SensitiveFilterService {
        private Map sensitiveWordMap = null;
        // 最小匹配规则
        public static int minMatchTYpe = 1;
        // 最大匹配规则
        public static int maxMatchType = 2;
        // 单例
        private static SensitiveFilterService instance = null;
        // 构造函数，初始化敏感词库
        private SensitiveFilterService() {
            sensitiveWordMap = new SensitiveWordInit().initKeyWord();
        }
        // 获取单例
        public static SensitiveFilterService getInstance() {
            if (null == instance) {
                instance = new SensitiveFilterService();
            }
            return instance;
        }
        // 获取文字中的敏感词
        public Set<String> getSensitiveWord(String txt, int matchType) {
            Set<String> sensitiveWordList = new HashSet<String>();
            for (int i = 0; i < txt.length(); i++) {
                // 判断是否包含敏感字符
                int length = CheckSensitiveWord(txt, i, matchType);
                // 存在,加入list中
                if (length > 0) {
                    sensitiveWordList.add(txt.substring(i, i + length));
                    // 减1的原因，是因为for会自增
                    i = i + length - 1;
                }
            }
            return sensitiveWordList;
        }
        // 替换敏感字字符
        public String replaceSensitiveWord(String txt, int matchType,
                                           String replaceChar) {
            String resultTxt = txt;
            // 获取所有的敏感词
            Set<String> set = getSensitiveWord(txt, matchType);
            Iterator<String> 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;
        }
     
        /**
         * 获取替换字符串
         * 
         * @param replaceChar
         * @param length
         * @return
         */
        private String getReplaceChars(String replaceChar, int length) {
            String resultReplace = replaceChar;
            for (int i = 1; i < length; i++) {
                resultReplace += replaceChar;
            }
            return resultReplace;
        }
     
     
        /**
         * 检查文字中是否包含敏感字符，检查规则如下：<br>
         * 如果存在，则返回敏感词字符的长度，不存在返回0
         * 
         * @param txt
         * @param beginIndex
         * @param matchType
         * @return
         */
        public int CheckSensitiveWord(String txt, int beginIndex, int matchType) {
            // 敏感词结束标识位：用于敏感词只有1位的情况
            boolean flag = false;
            // 匹配标识数默认为0
            int matchFlag = 0;
            Map nowMap = sensitiveWordMap;
            for (int i = beginIndex; i < txt.length(); i++) {
                char word = txt.charAt(i);
                // 获取指定key
                nowMap = (Map) nowMap.get(word);
                // 存在，则判断是否为最后一个
                if (nowMap != null) {
                // 找到相应key，匹配标识+1
                    matchFlag++;
                // 如果为最后一个匹配规则,结束循环，返回匹配标识数
                    if ("1".equals(nowMap.get("isEnd"))) {
                // 结束标志位为true
                        flag = true;
                        // 最小规则，直接返回,最大规则还需继续查找
                        if (SensitiveFilterService.minMatchTYpe == matchType) {
                            break;
                        }
                    }
                }
            // 不存在，直接返回
                else {
                    break;
                }
            }
            if (matchFlag < 2 && !flag) { // 长度必须大于等于1，为词
                matchFlag = 0;
            }
            return matchFlag;
        }
        public static void main(String[] args) {
            //需要屏蔽哪些字就在censorword.txt文档内添加即可
            SensitiveFilterService filter = SensitiveFilterService.getInstance();
            String txt = "去深圳参观，参观完后还得赶飞机去吃饭";
            //如果需要过滤则用“”替换
            //如果需要屏蔽，则用“*”替换
            String hou = filter.replaceSensitiveWord(txt, 1, "*");
            System.out.println("替换前的文字为：" + txt);
            System.out.println("替换后的文字为：" + hou);
        }
     
    }

初始化敏感词类 ：SensitiveWordInit

import java.io.BufferedReader;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.InputStreamReader;
    import java.util.HashMap;
    import java.util.HashSet;
    import java.util.Map;
    import java.util.Set;
    
    public class SensitiveWordInit {
    	// 字符编码
    	private String ENCODING = "UTF-8";
    	private String FILENAME = "C:\\Java\\censorwords.txt";
    	// 初始化敏感字库
    	public Map initKeyWord() {
    		// 读取敏感词库 ,存入Set中
    		Set<String> wordSet = readSensitiveWordFile();
    		// 将敏感词库加入到HashMap中//确定有穷自动机DFA
    		return addSensitiveWordToHashMap(wordSet);
    	}
    	// 读取敏感词库 ,存入HashMap中
    	private Set<String> readSensitiveWordFile() {
    		Set<String> wordSet = null;
    		// app为项目地址
    		/*
    		 * String app = System.getProperty("user.dir"); System.out.println(app);
    		 * URL resource = Thread.currentThread().getContextClassLoader()
    		 * .getResource("/"); String path = resource.getPath().substring(1);
    		 * System.out.println(path); File file = new File(path +
    		 * "censorwords.txt");
    		 */
    		//敏感词库
    		File file = new File(FILENAME);
    		try {
    			// 读取文件输入流
    			InputStreamReader read = new InputStreamReader(new FileInputStream(
    					file), ENCODING);
    			// 文件是否是文件 和 是否存在
    			if (file.isFile() && file.exists()) {
    				wordSet = new HashSet<String>();
    				// StringBuffer sb = new StringBuffer();
    				// BufferedReader是包装类，先把字符读到缓存里，到缓存满了，再读入内存，提高了读的效率。
    				BufferedReader br = new BufferedReader(read);
    				String txt = null;
    				// 读取文件，将文件内容放入到set中
    				while ((txt = br.readLine()) != null) {
    					wordSet.add(txt);
    				}
    				br.close();
    				/*
    				 * String str = sb.toString(); String[] ss = str.split("，"); for
    				 * (String s : ss) { wordSet.add(s); }
    				 */
    			}
    			// 关闭文件流
    			read.close();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		return wordSet;
    	}
    
    	// 将HashSet中的敏感词,存入HashMap中
    	private Map addSensitiveWordToHashMap(Set<String> wordSet) {
    		// 初始化敏感词容器，减少扩容操作
    		Map wordMap = new HashMap(wordSet.size());
    		for (String word : wordSet) {
    			Map nowMap = wordMap;
    			for (int i = 0; i < word.length(); i++) {
    				// 转换成char型
    				char keyChar = word.charAt(i);
    				// 获取
    				Object tempMap = nowMap.get(keyChar);
    				// 如果存在该key，直接赋值
    				if (tempMap != null) {
    					nowMap = (Map) tempMap;
    				}
    				// 不存在则，则构建一个map，同时将isEnd设置为0，因为他不是最后一个
    				else {
    					// 设置标志位
    					Map<String, String> newMap = new HashMap<String, String>();
    					newMap.put("isEnd", "0");
    					// 添加到集合
    					nowMap.put(keyChar, newMap);
    					nowMap = newMap;
    				}
    				// 最后一个
    				if (i == word.length() - 1) {
    					nowMap.put("isEnd", "1");
    				}
    			}
    		}
    		return wordMap;
    	}
    }

创建txt文件censorwords.txt，在文件中加入需要屏蔽的词  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE2NjEzMzEx_size_16_color_FFFFFF_t_70]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE2NjEzMzEx_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200303163348150.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE2NjEzMzEx,size_16,color_FFFFFF,t_70