一个简单的文字过滤

过滤的词汇用word.properties文件，用map的方式储存，放在项目中src目录下

定义一个过滤器KeywordFilter.class

package com.sobinterface.util;

import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

@SuppressWarnings({ "rawtypes", "unchecked" })
public class KeywordFilter {
    /** 直接禁止的 */
    private HashMap keysMap = new HashMap();
    private int matchType = 1; // 1:最小长度匹配 2：最大长度匹配

    public void addKeywords(List<String> keywords) {
        for (int i = 0; i < keywords.size(); i++) {
            String key = keywords.get(i).trim();
            HashMap nowhash = null;
            nowhash = keysMap;
            for (int j = 0; j < key.length(); j++) {
                char word = key.charAt(j);
                Object wordMap = nowhash.get(word);
                if (wordMap != null) {
                    nowhash = (HashMap) wordMap;
                } else {
                    HashMap<String, String> newWordHash = new HashMap<String, String>();
                    newWordHash.put("isEnd", "0");
                    nowhash.put(word, newWordHash);
                    nowhash = newWordHash;
                }
                if (j == key.length() - 1) {
                    nowhash.put("isEnd", "1");
                }
            }
        }
    }

    /** * 重置关键词 */
    public void clearKeywords() {
        keysMap.clear();
    }

    /** * 检查一个字符串从begin位置起开始是否有keyword符合， 如果有符合的keyword值，返回值为匹配keyword的长度，否则返回零 flag 1:最小长度匹配 2：最大长度匹配 */
    private int checkKeyWords(String txt, int begin, int flag) {
        HashMap nowhash = null;
        nowhash = keysMap;
        int maxMatchRes = 0;
        int res = 0;
        int l = txt.length();
        char word = 0;
        for (int i = begin; i < l; i++) {
            word = txt.charAt(i);
            Object wordMap = nowhash.get(word);
            if (wordMap != null) {
                res++;
                nowhash = (HashMap) wordMap;
                if (((String) nowhash.get("isEnd")).equals("1")) {
                    if (flag == 1) {
                        wordMap = null;
                        nowhash = null;
                        txt = null;
                        return res;
                    } else {
                        maxMatchRes = res;
                    }
                }
            } else {
                txt = null;
                nowhash = null;
                return maxMatchRes;
            }
        }
        txt = null;
        nowhash = null;
        return maxMatchRes;
    }

    /** * 返回txt中关键字的列表 */
    public Set<String> getTxtKeyWords(String txt) {
        Set set = new HashSet();
        int l = txt.length();
        for (int i = 0; i < l;) {
            int len = checkKeyWords(txt, i, matchType);
            if (len > 0) {
                set.add(txt.substring(i, i + len));
                i += len;
            } else {
                i++;
            }
        }
        txt = null;
        return set;
    }

    /** * 返回过滤违禁词后的列表，并且被替换为“*” */
    public String getFilerWords(String txt) {
        int l = txt.length();
        String filterWords = txt;
        for (int i = 0; i < l;) {
            int len = checkKeyWords(txt, i, matchType);
            if (len > 0) {
                filterWords = filterWords.replaceAll(txt.substring(i, i + len), "*");
                i += len;
            } else {
                i++;
            }
        }
        return filterWords;
    }

    /** * 仅判断txt中是否有关键字 */
    public boolean isContentKeyWords(String txt) {
        for (int i = 0; i < txt.length(); i++) {
            int len = checkKeyWords(txt, i, 1);
            if (len > 0) {
                return true;
            }
        }
        txt = null;
        return false;
    }

    public int getMatchType() {
        return matchType;
    }

    public void setMatchType(int matchType) {
        this.matchType = matchType;
    }
//
// public static void main(String[] args) {
// KeywordFilter filter = new KeywordFilter();
// Properties prop = new Properties();
// // 读取属性文件a.properties
// try {
// InputStream in = new BufferedInputStream(new FileInputStream("word.properties"));
// prop.load(in); // /加载属性列表
// Iterator<String> it = prop.stringPropertyNames().iterator();
// List<String> keywords = new ArrayList<String>();// 可以把这个列表变成word.properties文件（包含所有违禁词）
// while (it.hasNext()) {
// String key = it.next();
// keywords.add(key);
//// System.out.println(key + ":" + prop.getProperty(key));
// }
// filter.addKeywords(keywords);
// in.close();
// } catch(IOException e) {
// e.printStackTrace();
// }
//
// String txt = "中s国,人民站起卖国=来了，";
// boolean boo = filter.isContentKeyWords(txt);
// System.out.println(boo);
// Set set = filter.getTxtKeyWords(txt);
// System.out.println(set);
// System.out.println(filter.getFilerWords(txt));
// }
}

再定义一个MyProperties.class来读取properties文件里面的过滤词

package com.sobinterface.util;

import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.ResourceBundle;

public class MyProperties {

    private static KeywordFilter filter = new KeywordFilter();

    static {
// Properties prop = new Properties();
// try {
            ResourceBundle rb = ResourceBundle.getBundle("word");
            List<String> keywords = new ArrayList<String>();

            Enumeration<String> enume = rb.getKeys();
            while (enume.hasMoreElements()) {
                String key = enume.nextElement();
// System.out.println(key);
                keywords.add(key.toLowerCase());
            }
// InputStream in = new BufferedInputStream(new FileInputStream("../webapps/sob2/WEB-INF/classes/word.properties"));
// prop.load(in); 
// Iterator<String> it = prop.stringPropertyNames().iterator();
// while (it.hasNext()) {
// String key = it.next();
// keywords.add(key);
// System.out.println(key + ":" + prop.getProperty(key));
// }
            filter.addKeywords(keywords);
// in.close();
// } catch(IOException e) {
// e.printStackTrace();
// }
    }

    private MyProperties() {
    }

    public static KeywordFilter getFilter() {
        return filter;
    }

// public static void main(String args[]) {
// KeywordFilter filter = MyProperties.getFilter();
// System.out.println(filter.isContentKeyWords("sb"));
// }
}

最后在业务处理层service中把词语过滤，就OK了

// 检验评论是否存在违禁敏感词汇
KeywordFilter filter = MyProperties.getFilter();
commentText = commentText.toLowerCase();
if (filter.isContentKeyWords(commentText)) {
    return getMessageInfo(MessageEnum.VALIDATE_COMMENTTEXT_ERR);
}