设计模式之——责任链模式

1 责任链

package com.alvin;

public interface Filter {
    public String doFilter(String str);
}

package com.alvin;

public class HtmlFilter implements Filter{

    public String doFilter(String str) {
        return str.replace('<', '[').replace('>', ']');
    }

}

package com.alvin;

public class WordsFilter implements Filter{

    @Override
    public String doFilter(String str) {
        // TODO Auto-generated method stub
        return str.replace("铭感词", "河蟹");
    }
    
}

package com.alvin;

public class MesProcessor {
    private String msg;
    Filter [] filters = {new HtmlFilter(), new WordsFilter()};

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }
    
    public String process(){
        String r = msg;
        for (Filter f : filters) {
            r = f.doFilter(r);
        }
        return r;
    }
}

package com.alvin;

public class Main {
    public static void main(String[] args) {
        String msg = "<script>,:),kdkjfejfid, 敏感词:)";
        MesProcessor mp = new MesProcessor();
        mp.setMsg(msg);
        String result = mp.process();
        System.out.println(result);
    }
}

测试结果为：[script],:),kdkjfejfid, 河蟹:)

2 改进数组，采用ArrayList，增加FilterChain类

package com.alvin;

import java.util.ArrayList;
import java.util.List;

public class FilterChain {
    List<Filter> filters = new ArrayList<>();

    public void addFilter(Filter f) {
        filters.add(f);
    }

    public String doFilter(String str) {
        for (Filter filter : filters) {
            str = filter.doFilter(str);
        }
        return str;
    }
}

修改MesProcessor

package com.alvin;

public class MesProcessor {
    private String msg;
    FilterChain filterChain;

    public FilterChain getFilterChain() {
        return filterChain;
    }

    public void setFilterChain(FilterChain filterChain) {
        this.filterChain = filterChain;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public String process() {
        return filterChain.doFilter(msg);
    }
}

测试类

package com.alvin;

public class Main {
    public static void main(String[] args) {
        String msg = "<script>,:),kdkjfejfid, 敏感词:)";
        MesProcessor mp = new MesProcessor();
        mp.setMsg(msg);
        FilterChain filterChain = new FilterChain();
        filterChain.addFilter(new HtmlFilter());
        filterChain.addFilter(new WordsFilter());
        mp.setFilterChain(filterChain);
        String result = mp.process();
        System.out.println(result);
    }
}

测试结果：[script],:),kdkjfejfid, 河蟹:)