Java过滤敏感词

素颜马尾好姑娘i 2021-12-22 03:25 311阅读 0赞

新建SensitiveWordInit类文件

package com.zns.test;
    
    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.Iterator;
    import java.util.Map;
    import java.util.Set;
    
    /**
     * @Description: 初始化敏感词库，将敏感词加入到HashMap中，构建DFA算法模型
     */
    public class SensitiveWordInit {
        public String ENCODING = "GBK";    //字符编码
        @SuppressWarnings("rawtypes")
        public HashMap sensitiveWordMap;
        
        public SensitiveWordInit(){
            super();
        }
        
        @SuppressWarnings("rawtypes")
        public Map initKeyWord(File file){
            try {
                //读取敏感词库
                Set<String> keyWordSet = readSensitiveWordFile(file);
                //将敏感词库加入到HashMap中
                addSensitiveWordToHashMap(keyWordSet);
                //spring获取application，然后application.setAttribute("sensitiveWordMap",sensitiveWordMap);
            } catch (Exception e) {
                e.printStackTrace();
            }
            return sensitiveWordMap;
        }
    
        /**
         * 读取敏感词库，将敏感词放入HashSet中，构建一个DFA算法模型：<br>
         * 中 = {
         *      isEnd = 0
         *      国 = {<br>
         *           isEnd = 1
         *           人 = {isEnd = 0
         *                民 = {isEnd = 1}
         *                }
         *           男  = {
         *                  isEnd = 0
         *                   人 = {
         *                        isEnd = 1
         *                       }
         *               }
         *           }
         *      }
         *  五 = {
         *      isEnd = 0
         *      星 = {
         *          isEnd = 0
         *          红 = {
         *              isEnd = 0
         *              旗 = {
         *                   isEnd = 1
         *                  }
         *              }
         *          }
         *      }
         * @param keyWordSet  敏感词库
         */
        @SuppressWarnings({ "rawtypes", "unchecked" })
        private void addSensitiveWordToHashMap(Set<String> keyWordSet) {
            sensitiveWordMap = new HashMap(keyWordSet.size());     //初始化敏感词容器，减少扩容操作
            String key = null;  
            Map nowMap = null;
            Map<String, String> newWorMap = null;
            //迭代keyWordSet
            Iterator<String> iterator = keyWordSet.iterator();
            while(iterator.hasNext()){
                key = iterator.next();    //关键字
                nowMap = sensitiveWordMap;
                for(int i = 0 ; i < key.length() ; i++){
                    char keyChar = key.charAt(i);       //转换成char型
                    Object wordMap = nowMap.get(keyChar);       //获取
                    
                    if(wordMap != null){        //如果存在该key，直接赋值
                        nowMap = (Map) wordMap;
                    }
                    else{     //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
                        newWorMap = new HashMap<String,String>();
                        newWorMap.put("isEnd", "0");     //不是最后一个
                        nowMap.put(keyChar, newWorMap);
                        nowMap = newWorMap;
                    }
                    
                    if(i == key.length() - 1){
                        nowMap.put("isEnd", "1");    //最后一个
                    }
                }
            }
        }
    
        /**
         * 读取敏感词库中的内容，将内容添加到set集合中 
         */
        @SuppressWarnings("resource")
        private Set<String> readSensitiveWordFile(File file) throws Exception{
            Set<String> set = null;
            
            InputStreamReader read = new InputStreamReader(new FileInputStream(file),ENCODING);
            try {
                if(file.isFile() && file.exists()){      //文件流是否存在
                    set = new HashSet<String>();
                    BufferedReader bufferedReader = new BufferedReader(read);
                    String txt = null;
                    while((txt = bufferedReader.readLine()) != null){    //读取文件，将文件内容放入到set中
                        set.add(txt);
                    }
                }
                else{         //不存在抛出异常信息
                    throw new Exception("敏感词库文件不存在");
                }
            } catch (Exception e) {
                throw e;
            }finally{
                read.close();     //关闭文件流
            }
            return set;
        }
    }

新建SensitivewordFilter类文件

package com.zns.test;
    
    import java.io.File;
    import java.util.HashSet;
    import java.util.Iterator;
    import java.util.Map;
    import java.util.Set;
    
    /**
     * @Description: 敏感词过滤
     */
    public class SensitivewordFilter {
        @SuppressWarnings("rawtypes")
        private Map sensitiveWordMap = null;
        public static int minMatchTYpe = 1;      //最小匹配规则
        public static int maxMatchType = 2;      //最大匹配规则
        
        /**
         * 构造函数，初始化敏感词库
         */
        public SensitivewordFilter(File file){
            sensitiveWordMap = new SensitiveWordInit().initKeyWord(file);
        }
        
        /**
         * 判断文字是否包含敏感字符
         * @param txt  文字
         * @param matchType  匹配规则 1：最小匹配规则，2：最大匹配规则
         * @return 若包含返回true，否则返回false
         */
        public boolean isContaintSensitiveWord(String txt,int matchType){
            boolean flag = false;
            for(int i = 0 ; i < txt.length() ; i++){
                int matchFlag = this.CheckSensitiveWord(txt, i, matchType); //判断是否包含敏感字符
                if(matchFlag > 0){    //大于0存在，返回true
                    flag = true;
                }
            }
            return flag;
        }
        
        /**
         * 获取文字中的敏感词
         * @param txt 文字
         * @param matchType 匹配规则 1：最小匹配规则，2：最大匹配规则
         * @return
         */
        public Set<String> getSensitiveWord(String txt , int matchType){
            Set<String> sensitiveWordList = new HashSet<String>();
            
            for(int i = 0 ; i < txt.length() ; i++){
                int length = CheckSensitiveWord(txt, i, matchType);    //判断是否包含敏感字符
                if(length > 0){    //存在,加入list中
                    sensitiveWordList.add(txt.substring(i, i+length));
                    i = i + length - 1;    //减1的原因，是因为for会自增
                }
            }
            
            return sensitiveWordList;
        }
        
        /**
         * 替换敏感字字符
         * @param txt
         * @param matchType
         * @param replaceChar 替换字符，默认*
         */
        public String replaceSensitiveWord(String txt,int matchType,String replaceChar){
            String resultTxt = txt;
            Set<String> set = getSensitiveWord(txt, matchType);     //获取所有的敏感词
            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>
         * @param txt
         * @param beginIndex
         * @param matchType
         * @return，如果存在，则返回敏感词字符的长度，不存在返回0
         */
        @SuppressWarnings({ "rawtypes"})
        public int CheckSensitiveWord(String txt,int beginIndex,int matchType){
            boolean  flag = false;    //敏感词结束标识位：用于敏感词只有1位的情况
            int matchFlag = 0;     //匹配标识数默认为0
            char word = 0;
            Map nowMap = sensitiveWordMap;
            for(int i = beginIndex; i < txt.length() ; i++){
                word = txt.charAt(i);
                nowMap = (Map) nowMap.get(word);     //获取指定key
                if(nowMap != null){     //存在，则判断是否为最后一个
                    matchFlag++;     //找到相应key，匹配标识+1 
                    if("1".equals(nowMap.get("isEnd"))){       //如果为最后一个匹配规则,结束循环，返回匹配标识数
                        flag = true;       //结束标志位为true   
                        if(SensitivewordFilter.minMatchTYpe == matchType){    //最小规则，直接返回,最大规则还需继续查找
                            break;
                        }
                    }
                }
                else{     //不存在，直接返回
                    break;
                }
            }
            if(matchFlag < 2 || !flag){        //长度必须大于等于1，为词 
                matchFlag = 0;
            }
            return matchFlag;
        }
        
    }

敏感词SensitiveWord.txt文件内容如下

小电影

aaa

bbb

代码测试

public static void main(String[] args) {
        //敏感词txt文件 放到eclipse可能会有乱码，右键属性改成GBK格式即可
        //File file = new File("D:\\SensitiveWord.txt");
            File file = new File(Test1.class.getClassLoader().getResource("SensitiveWord.txt").getFile());
        SensitivewordFilter filter = new SensitivewordFilter(file);
        System.out.println("敏感词的数量：" + filter.sensitiveWordMap.size());
        String str = "小电影啊啊啊啊电影";
        System.out.println("待检测语句字数：" + str.length());
        long beginTime = System.currentTimeMillis();
        Set<String> set = filter.getSensitiveWord(str, 1);
        long endTime = System.currentTimeMillis();
        System.out.println("语句中包含敏感词的个数为：" + set.size() + "。包含：" + set);
        System.out.println("是否包含敏感词："+filter.isContaintSensitiveWord(str, 1));
        System.out.println("替换敏感词为*："+filter.replaceSensitiveWord(str, 1, "*"));
        System.out.println("总共消耗时间为：" + (endTime - beginTime));
    }

转载于:https://www.cnblogs.com/zengnansheng/p/10385845.html