字符串匹配：KMP算法之JAVA实现

前几天同学说让我写个字符串匹配，我就想到了KMP，学了下结论很简单，至于证明就没太细看了，结果写完人家说不用了、、、我想着不能白写。so，拍到博客上。
算法讲解：http://www.ruanyifeng.com/blog/2013/05/Knuth%E2%80%93Morris%E2%80%93Pratt_algorithm.html
这里讲的简单易懂，反正我看完代码就写出来了。
然后代码附上：

package stringmatch;

import java.util.*;

/** * Created by Lee Y on 2016/5/4. * 应用：kmp算法 */
public final class StringMatch {
    public static final StringMatch match = new StringMatch();
    private StringMatch(){}
    /* 获得字符串匹配表 */
    private int[] getMatchList(char[] string){
        int l = string.length;
        int[] matchList = new int[l];
        matchList[0] = 0;
        char temp = string[0];
        char temp1,current;
        int matchValue;
        for(int i=1; i<l; i++){
            matchValue = matchList[i-1];
            current = string[i];
            if(matchValue == 0){
                if(temp == current){
                    matchList[i]++;
                }
            }else{
                temp1 = string[matchValue];
                if(current == temp1){
                    matchList[i] = matchValue+1;
                }
            }
        }
        return matchList;
    }
    private boolean match(String matched, String demand, int[] matchList){
        int matched_point = 0, demand_point = 0;
        int l_matched = matched.length();
        int l_demand = demand.length();
        char current_matched, current_demand;
        int matchedLength = 0, move = 0;
        while(matched_point < l_matched && demand_point < l_demand){
            current_matched = matched.charAt(matched_point);
            current_demand = demand.charAt(demand_point);
            if(current_demand == current_matched){
                matchedLength++;
                matched_point++;
                demand_point++;
            }else{
                move = matchedLength - matchList[demand_point];
                if(move != 0){
                    demand_point -= move;
                    matchedLength -= move;
                }else{
                    matched_point++;
                }
            }
            if(matchedLength == l_demand){
                return true;
            }

        }
        return false;
    }
    public MatchFactory getMatchFactory(){
        return new MatchFactory();
    }
    public class MatchFactory{
        public List getRelateMess(List<String> l, String d){
            int[] matchList = getMatchList(d.toCharArray());
            for (int i:matchList){
                System.out.println(i);
            }
            List<String> list = new ArrayList<>();
            for(String s : l){
                if(match(s,d,matchList) == true){
                    list.add(s);
                }
            }
            return list;
        }
    }
    /* 本类的静态方法可以调用本类的私有构造器 */
    public static void main(String[] args) {
        StringMatch.MatchFactory sm = match.getMatchFactory();
        List<String> list = sm.getRelateMess(l,"我是李灯具，我是李柏炎，我是相许为。");
        for (String s : list){
            System.out.println(s);
        }
    }
    public static List<String> l = new ArrayList<>();
    static {
        for(int i=0;i<100000;i++){
            l.add("HTML基础语法\n" +
                    "设计人员，负责设计界面\n" +
                    "开发人员，拿到界面开始写代码\n" +
                    "简历用低版本\n" +
                    "\n" +
                    "jsp：\n" +
                    "AS：应用服务器，例如tomcat（服务器集群比较好，把n多服务器当一个服务器用）、jboss（内存上限2g左右）\n" +
                    "我是李灯具，我是李柏炎，我是相许为。" +
                    "Servlet：\n" +
                    "JDBC：数据库连接器 ,JAVA\n" +
                    "\n");
        }
    }
}

看懂了应该不难理解，所以没有过多的做注释。