非法关键词过滤

src/main/java/com/uas/platform/b2c/core/utils/KeyWordFilterUtil.java

@@ -0,0 +1,99 @@
+package com.uas.platform.b2c.core.utils;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * 敏感词DFA算法实现
+ */
+public class KeyWordFilterUtil {
+    public static int minMatchTYpe = 1;      //最小匹配规则
+    public static int maxMatchType = 2;      //最大匹配规则
+
+    public static Set<String> getSensitiveWord(String txt , int matchType,Map nowMap) {
+        Set<String> sensitiveWordList = new HashSet<String>();
+
+        for (int i = 0; i < txt.length(); i++) {
+            int length = CheckSensitiveWord(txt,i, matchType,nowMap);    //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;
+    }
+    /**
+     * 检查文字中是否包含敏感字符
+     */
+    public static int CheckSensitiveWord(String txt,int beginIndex,int matchType,Map nowMap){
+        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;
+        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(KeyWordFilterUtil.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;
+    }
+
+    /**
+     * 初始化敏感词
+     * @param keyWordSet
+     * @return
+     */
+    public static Map initKeyWord(Set<String> keyWordSet){
+        HashMap sensitiveWordMap = null;
+        try {
+            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
+                    }
+                }
+            }
+            //spring获取application，然后application.setAttribute("sensitiveWordMap",sensitiveWordMap);
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+        return sensitiveWordMap;
+    }
+}