大话设计模式之---责任链模式

责任链模式，又称职责链模式，Chain Of Responsibility，使多个对象都有机会处理请求，从而避免请求的发送者和接收者之间的耦合关系，将这个对象连成一条链，并沿着这条链传递该请求，直到有一个对象处理它为止。

    根据代码来体验，模仿前端消息传递过滤。

package com.kk;
/**
 * @author zhaokk
 * @create 2019-12-08-10:06
 */
public class ChainOfResponsibility {
    public static void main(String[] args) {
        Msg msg = new Msg();
        //消息接收
        msg.setMsg("你好:),<script>,欢迎的来到996icu");
        String str=msg.getMsg();
        str = str.replace('<', '[');
        str= str.replace('>',']');
        msg.setMsg(str);
        str= str.replaceAll("996icu","955happy");
        msg.setMsg(str);
        //过滤
        System.out.println(msg.getMsg());
    }
}

class Msg {
    String name;
    String msg;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getMsg() {
        return msg;
    }

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

    @Override
    public String toString() {
        return "Msg{" +
                "name='" + name + '\'' +
                ", msg='" + msg + '\'' +
                '}';
    }
}

输出：

D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\bin\java.exe "-javaagent:D:\idea\IntelliJ IDEA 2019.1.1\lib\idea_rt.jar=51670:D:\idea\IntelliJ IDEA 2019.1.1\bin" -Dfile.encoding=UTF-8 -classpath D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\charsets.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\deploy.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\access-bridge-64.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\cldrdata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\dnsns.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jaccess.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jfxrt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\localedata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\nashorn.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunec.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunjce_provider.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunmscapi.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunpkcs11.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\zipfs.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\javaws.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jce.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfr.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfxswt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jsse.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\management-agent.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\plugin.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\resources.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\rt.jar;D:\project01\target\classes;C:\Users\14620\.m2\repository\commons-logging\commons-logging\1.1.3\commons-logging-1.1.3.jar;C:\Users\14620\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-classic\1.1.7\logback-classic-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-core\1.1.7\logback-core-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-access\1.1.7\logback-access-1.1.7.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-core\2.5\log4j-core-2.5.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-api\2.5\log4j-api-2.5.jar;C:\Users\14620\.m2\repository\junit\junit\4.12\junit-4.12.jar;C:\Users\14620\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar com.kk.ChainOfResponsibility
你好:),[script],欢迎的来到955happy

Process finished with exit code 0

这里的消息指request请求获取缓存中消息，或者用户输入消息，当进行消息过滤时，添加一个特殊符号过滤，添加一个敏感词过滤处理消息。但当增加需求或者改变敏感词时，需要增加新功能，且耦合较高。

将变化的代码逻辑封装变化

处理信息的部分是变化的

我们定义一个接口为Filter

package com.kk;
/**
 * @author zhaokk
 * @create 2019-12-08-10:24
 */
public interface Filter {
    void dofilter(Msg msg);
}

处理信息的两个实现类

package com.kk;

/**
 * 特殊符号
 * @author zhaokk
 * @create 2019-12-08-10:26
 */
public class SpecialFilter implements Filter{
    public void dofilter(Msg msg) {
        String str=msg.getMsg();
        str = str.replace('<', '[');
        str= str.replace('>',']');
        msg.setMsg(str);
    }
}

package com.kk;

/**
 * 敏感词
 * @author zhaokk
 * @create 2019-12-08-10:27
 */
public class SensitiveFilter implements Filter {

    public void dofilter(Msg msg) {
        String str=msg.getMsg();
        str= str.replaceAll("996icu","955happy");
        msg.setMsg(str);
    }
}

public class ChainOfResponsibility {
    public static void main(String[] args) {
        Msg msg = new Msg();
        msg.setMsg("你好:),<script>,欢迎的来到996icu");
        new SpecialFilter().dofilter(msg);
        new SensitiveFilter().dofilter(msg);
       /* String str=msg.getMsg();
        str = str.replace('<', '[');
        str= str.replace('>',']');
        msg.setMsg(str);
        str= str.replaceAll("996icu","955happy");
        msg.setMsg(str);*/
        System.out.println(msg.getMsg());
    }
}

输出：

D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\bin\java.exe "-javaagent:D:\idea\IntelliJ IDEA 2019.1.1\lib\idea_rt.jar=52130:D:\idea\IntelliJ IDEA 2019.1.1\bin" -Dfile.encoding=UTF-8 -classpath D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\charsets.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\deploy.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\access-bridge-64.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\cldrdata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\dnsns.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jaccess.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jfxrt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\localedata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\nashorn.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunec.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunjce_provider.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunmscapi.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunpkcs11.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\zipfs.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\javaws.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jce.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfr.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfxswt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jsse.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\management-agent.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\plugin.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\resources.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\rt.jar;D:\project01\target\classes;C:\Users\14620\.m2\repository\commons-logging\commons-logging\1.1.3\commons-logging-1.1.3.jar;C:\Users\14620\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-classic\1.1.7\logback-classic-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-core\1.1.7\logback-core-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-access\1.1.7\logback-access-1.1.7.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-core\2.5\log4j-core-2.5.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-api\2.5\log4j-api-2.5.jar;C:\Users\14620\.m2\repository\junit\junit\4.12\junit-4.12.jar;C:\Users\14620\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar com.kk.ChainOfResponsibility
你好:),[script],欢迎的来到955happySun Dec 08 10:32:19 CST 2019
Process finished with exit code 0

但是此时如果新的业务逻辑进入还需要定义并引入Filter，如果将所有的Filter放入List，foreachList，也可以将多个Filter穿起来，但是新的Filter增加特需要add。且循环过程中，需要所有Filter过滤完才放出.定义一个

FilterChain

ackage com.kk;

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

/**
 * @author zhaokk
 * @create 2019-12-08-10:40
 */
public class FilterChain {
    List<Filter> filterList=new ArrayList<Filter>();
    private Msg msg;

    public void add(Filter filter){
        filterList.add(filter);
    }
    public void  doFilter(Msg msg){
        for (Filter filter : filterList) {
            filter.dofilter(msg);
        }
    }
}

处理逻辑

public class ChainOfResponsibility {
    public static void main(String[] args) {
        Msg msg = new Msg();
        msg.setMsg("你好:),<script>,欢迎的来到996icu");
        FilterChain fc = new FilterChain();
        fc.add(new SpecialFilter());
        fc.add(new SensitiveFilter());
        fc.doFilter(msg);
       /* String str=msg.getMsg();
        str = str.replace('<', '[');
        str= str.replace('>',']');
        msg.setMsg(str);
        str= str.replaceAll("996icu","955happy");
        msg.setMsg(str);*/
        System.out.println(msg.getMsg()+new Date());
    }
}

输出：

D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\bin\java.exe "-javaagent:D:\idea\IntelliJ IDEA 2019.1.1\lib\idea_rt.jar=52490:D:\idea\IntelliJ IDEA 2019.1.1\bin" -Dfile.encoding=UTF-8 -classpath D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\charsets.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\deploy.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\access-bridge-64.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\cldrdata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\dnsns.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jaccess.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jfxrt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\localedata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\nashorn.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunec.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunjce_provider.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunmscapi.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunpkcs11.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\zipfs.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\javaws.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jce.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfr.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfxswt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jsse.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\management-agent.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\plugin.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\resources.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\rt.jar;D:\project01\target\classes;C:\Users\14620\.m2\repository\commons-logging\commons-logging\1.1.3\commons-logging-1.1.3.jar;C:\Users\14620\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-classic\1.1.7\logback-classic-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-core\1.1.7\logback-core-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-access\1.1.7\logback-access-1.1.7.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-core\2.5\log4j-core-2.5.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-api\2.5\log4j-api-2.5.jar;C:\Users\14620\.m2\repository\junit\junit\4.12\junit-4.12.jar;C:\Users\14620\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar com.kk.ChainOfResponsibility
你好:),[script],欢迎的来到955happySun Dec 08 10:53:22 CST 2019
Process finished with exit code 0

此时我们再增加一个对消息处理的RedisFilter，

package com.kk;
/**
 * @author zhaokk
 * @create 2019-12-08-10:58
 */
public class RedisFilter implements Filter {
    public void doFilter(Msg msg) {
        String rediskry="TH"+msg;
        rediskry.replace(":)","");
        msg.setMsg(rediskry);
    }
}

然后让FilterChain也实现Filter接口

public static void main(String[] args) {
        Msg msg = new Msg();
        msg.setMsg("你好:),<script>,欢迎的来到996icu");


        FilterChain fc = new FilterChain();
        fc.add(new SpecialFilter())
                .add(new SensitiveFilter());
        FilterChain fc2 = new FilterChain();
        fc2.add(new RedisFilter());
        fc2.doFilter(msg);
        fc.doFilter(msg);
        //fc.add(new SensitiveFilter());
       /* String str=msg.getMsg();
        str = str.replace('<', '[');
        str= str.replace('>',']');
        msg.setMsg(str);
        str= str.replaceAll("996icu","955happy");
        msg.setMsg(str);*/
        System.out.println(msg.getMsg()+new Date());
    }

但是这里的消息，必须一条责任链处理完，另一条责任链也要处理

将一个链条看做是Filter加到FilterChain链中

fc.add(fc2);

在某一个filter中决定是否继续往下处理

将Filter返回boolean

public interface Filter {
    Boolean doFilter(Msg msg);
}

其他三个过滤器除敏感词返回false外返回true

public class SensitiveFilter implements Filter {
    public Boolean doFilter(Msg msg) {
        String str=msg.getMsg();
        str= str.replaceAll("996icu","955happy");
        msg.setMsg(str);
        return false;
    }
}

在filterChain中

public Boolean doFilter(Msg msg) {
        for (Filter filter : filterList) {
            if (!filter.doFilter(msg)) {
                return false;
            }
        }
        return true;
    }

此时在三个责任链中第二个是返回false，第三个是不予执行的，RedisFilter效果不被执行

D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\bin\java.exe "-javaagent:D:\idea\IntelliJ IDEA 2019.1.1\lib\idea_rt.jar=52994:D:\idea\IntelliJ IDEA 2019.1.1\bin" -Dfile.encoding=UTF-8 -classpath D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\charsets.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\deploy.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\access-bridge-64.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\cldrdata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\dnsns.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jaccess.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\jfxrt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\localedata.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\nashorn.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunec.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunjce_provider.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunmscapi.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\sunpkcs11.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\ext\zipfs.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\javaws.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jce.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfr.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jfxswt.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\jsse.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\management-agent.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\plugin.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\resources.jar;D:\ProgramFiles\JavaTest\java\jdk1.8.0_141\jre\lib\rt.jar;D:\project01\target\classes;C:\Users\14620\.m2\repository\commons-logging\commons-logging\1.1.3\commons-logging-1.1.3.jar;C:\Users\14620\.m2\repository\log4j\log4j\1.2.17\log4j-1.2.17.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\14620\.m2\repository\org\slf4j\slf4j-log4j12\1.7.7\slf4j-log4j12-1.7.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-classic\1.1.7\logback-classic-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-core\1.1.7\logback-core-1.1.7.jar;C:\Users\14620\.m2\repository\ch\qos\logback\logback-access\1.1.7\logback-access-1.1.7.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-core\2.5\log4j-core-2.5.jar;C:\Users\14620\.m2\repository\org\apache\logging\log4j\log4j-api\2.5\log4j-api-2.5.jar;C:\Users\14620\.m2\repository\junit\junit\4.12\junit-4.12.jar;C:\Users\14620\.m2\repository\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar com.kk.ChainOfResponsibility
你好:),[script],欢迎的来到955happySun Dec 08 11:22:49 CST 2019
Process finished with exit code 0

模拟Severlet API Filter

如何在一条责任链处理request与response

response向上返回处理结果

当Filter处理request的时候，让当前的Filter找到下一个Filter，下一个Filter如此，直到处理完再处理response然后向上返回response至第一层

package com.kk;

/**
 * @author zhaokk
 * @create 2019-12-08-10:24
 */
public interface Filter {
    Boolean doFilter(Request request, Response response,FilterChain filterChain);
}

接受者和发送者都没有对方的明确消息，且链中的对象结构也不知道链的结构，职责链可以简化对象的相互连接，且易于扩展

package com.kk;

/**
 * @author zhaokk
 * @create 2019-12-08-10:26
 */
public class SpecialFilter implements Filter {
    public void doFilter(Request request, Response response, FilterChain filterChain) {
        request.setStr(request.getStr().replace('<', '[').replace(">", "]") + "---SpecialFilter()");
        filterChain.doFilter(request, response, filterChain);
        response.setStr(response.getStr() + "---SpecialFilter()");
    }
}

package com.kk;

/**
 * @author zhaokk
 * @create 2019-12-08-10:58
 */
public class RedisFilter implements Filter {
    public void doFilter(Request request, Response response,FilterChain filterChain) {
        String rediskry="TH"+request.getStr();
        request.setStr(rediskry.replace(":)","") + "---SpecialFilter()");
        filterChain.doFilter(request, response, filterChain);
    }
}

FilterChain

package com.kk;
        import java.util.ArrayList;        import java.util.List;
/** * @author zhaokk * @create 2019-12-08-10:40 */public class FilterChain implements Filter {
    List<Filter> filterList = new ArrayList<Filter>();    private Msg msg;
    public FilterChain add(Filter filter) {        filterList.add(filter);        return this;    }
    public void doFilter(Request request, Response response,FilterChain filterChain) {
        filterChain.doFilter(request,response,filterChain);    }}

package com.kk;
        import java.util.ArrayList;        import java.util.List;
/** * @author zhaokk * @create 2019-12-08-10:40 */public class FilterChain implements Filter {
    List<Filter> filterList = new ArrayList<Filter>();    private Msg msg;
    public FilterChain add(Filter filter) {        filterList.add(filter);        return this;    }
    public void doFilter(Request request, Response response,FilterChain filterChain) {
        filterChain.doFilter(request,response,filterChain);    }}

关于设计模式有23种之多，平时看过，只是并不能强化记忆，除了自己做的demo外，很少能第二次用于平时项目，针对性学习，更能加强记忆

为什么平时看资料会累，因为

第一漫无目的

第二看完得不到应用

第三根本不感兴趣

所以有些书，有些视频资料，看一段时间就坚持不下去了

单纯通过公众号学习一门技术是不现实的，只是记录下当下关注的技术点，并不能够达到教学的级别，个人也比较随意，对有些人有帮助，他就觉得你不错，对别人来说没帮助，那就很水，但我的目的不在这，我只是享受多年后回来看的那种成就感

平时一有什么想法我会及时记录到随笔中，并以此为乐趣，有时我们难于表达，这些随笔能记录并激发你的表达能力