day21

책임연쇄패턴

 

 

1. java 1

next chain을 받는 함수를 만드는 것이 아니라  LinkedList를 이용했습니다.

 

package chainofresposibility;

import java.util.LinkedList;
import java.util.List;

public class Main {
    public static void main(String[] args) {
        LoggerManager manager = new LoggerManager();
        manager.setLogger(new ConsoleLogger(LoggerManager.ERROR));
        manager.setLogger(new FileLogger(LoggerManager.WRAN));

        manager.write(LoggerManager.ERROR,"eeeeeeeeeee");
        manager.write(LoggerManager.WRAN,"wwwwwwwwwww");
        manager.write(LoggerManager.DEBUG,"ddddddddddd");
    }
}

interface ILogger{
    void write(int level, String msg);
}

class LoggerManager implements  ILogger{

    public static int ERROR  = 3;
    public static int WRAN = 2;
    public static int DEBUG = 1;

    private List<ILogger> loggers = new LinkedList<>();

    public void setLogger(ILogger logger){
        loggers.add(logger);
    }

    @Override
    public void write(int level, String msg) {
        for(ILogger l : loggers){
            l.write(level, msg);
        }
    }
}

class ConsoleLogger implements ILogger{

    private int levels;

    ConsoleLogger(int levels){
        this.levels = levels;
    }

    @Override
    public void write(int levels, String msg) {
        if(this.levels<=levels){
            System.out.println("ConsoleLogger : "+msg);
        }
    }
}

class FileLogger implements ILogger{
    private int levels;

    FileLogger(int levels){
        this.levels = levels;
    }

    @Override
    public void write(int levels, String msg) {
        if(this.levels<=levels){
            System.out.println("FileLogger : "+msg);
        }
    }
}

결과

ConsoleLogger : eeeeeeeeeee
FileLogger : eeeeeeeeeee
FileLogger : wwwwwwwwwww

Process finished with exit code 0

 

 

 

2. java

이것은 next chain을 호출합다. 1, 2번 다 연속으로 호출됩니다.

package chanofresposibility;

public class Main {

    public static void main(String[] args) {
        System.out.println("main");
        Logger consoleLogger = new ConsoleBasedLogger(Logger.OUTPUT);

        Logger debugLogger = new DebugBasedLogger(Logger.DEBUG);
        consoleLogger.setNextLogger(debugLogger);

        Logger errorLogger = new ErrorBasedLogger(Logger.ERROR);
        debugLogger.setNextLogger(errorLogger);


        consoleLogger.logMessage(Logger.OUTPUT, "111111111111 ");
        consoleLogger.logMessage(Logger.ERROR, "222222222222");
        consoleLogger.logMessage(Logger.DEBUG, "3333333333333");
    }

}


abstract class Logger{
    public static int OUTPUT = 1;
    public static int ERROR  = 2;
    public static int DEBUG = 3;

    protected int levels;
    protected Logger nextLogger;

    public void setNextLogger(Logger nextLogger){
        this.nextLogger = nextLogger;
    }

    public void logMessage(int levels, String msg){
        if(this.levels <= levels){
            displayLogInfo(msg);
        }
        if(nextLogger != null){
            nextLogger.logMessage(levels, msg);
        }
    }

    protected abstract void displayLogInfo(String msg);
}

class ConsoleBasedLogger extends Logger{
    public ConsoleBasedLogger(int levels){
        this.levels = levels;
    }

    @Override
    protected void displayLogInfo(String msg) {
        System.out.println(("ConsoleBasedLogger : "+msg));
    }
}

class DebugBasedLogger  extends Logger{
    public DebugBasedLogger (int levels){
        this.levels = levels;
    }

    @Override
    protected void displayLogInfo(String msg) {
        System.out.println(("    DebugBasedLogger : "+msg));
    }
}

class ErrorBasedLogger extends Logger {
    public ErrorBasedLogger(int levels) {
        this.levels=levels;
    }

    @Override
    protected void displayLogInfo(String msg) {
        System.out.println("        ErrorBasedLogger : "+msg);
    }
}

 

 

 

3. kotlin

이건 좀 다른 예제 입니다. 코틀린 이여서 한 번 따라 해 봤습니다.

package chainofresponsibility


fun main() {
   println("chain of ")
    // 연쇄적인 엘리먼트 만들기
    val authenticationHeader = AuthHeader("123456")
    val contentTypeHeader = ContentTypeHeader("json")
    val messageBody = BodyPayload("Body:\n{\n\"username\"=\"dbacinski\"\n}")

// 체인 구조
    authenticationHeader.next = contentTypeHeader
    contentTypeHeader.next = messageBody

// 체인 실행
    val messageWithAuthentication = authenticationHeader.addHeader("Headers with Authentication:\n")
    println(messageWithAuthentication)

    val messageWithoutAuth = contentTypeHeader.addHeader("Headers:\n")
    println(messageWithoutAuth)

}

interface HeaderChain{
    fun addHeader(inputHeader:String):String
}

class AuthHeader(val token:String?, var next:HeaderChain?=null):HeaderChain{
    override fun addHeader(inputHeader: String): String {
        token?: throw IllegalStateException("Token should be not null")

        println(">>>> AuthHeader   ${inputHeader}")

        return inputHeader + "Auth : ${token}\n".let {
            println(">>>>     ContentTypeHeader it ${it}")
            next?.addHeader(it)?:it
        }
    }
}

class ContentTypeHeader(val contentType:String, var next:HeaderChain?=null) : HeaderChain{
    override fun addHeader(inputHeader: String): String {
        println(">>>> ContentTypeHeader   ${inputHeader}")

        return inputHeader + "ContentType:${contentType}\n".let {
            println(">>>>     ContentTypeHeader it ${it}")
            next?.addHeader(it) ?: it
        }
    }
}

class BodyPayload(val body:String, var next:HeaderChain? = null) : HeaderChain{
    override fun addHeader(inputHeader: String): String {
        println(">>>> BodyPayload   ${inputHeader}")
        return inputHeader +" $body".let {
            println(">>>>   BodyPayload it  ${it}")
            next?.addHeader(it)?:it
        }
    }
}

//https://medium.com/hongbeomi-dev/design-pattern-in-kotlin-1-behavioral-7185d0f71aea
//https://develogs.tistory.com/18