责任链模式（Chain of Responsibility Pattern）为请求创建了一个接收者对象的链。这种模式给予请求的类型，对请求的发送者和接收者进行解耦，本人根据https://www.runoob.com/design-pattern/chain-of-responsibility-pattern.html所给的例子，用Matlab代码实现责任链模式

AbstractLogger.m

classdef AbstractLogger < handle & matlab.mixin.Heterogeneous
properties(Constant)
INFO = 1;
DEBUG = 2;
ERROR = 3;
end
properties(Access = protected)
level
nextLogger = AbstractLogger.empty();
end
methods(Abstract,Access = protected)
write(~);
end
methods
function setNextLogger(obj,nextLogger)
obj.nextLogger = nextLogger;
end

    function logMessage(obj,level,message)  
        if(obj.level <= level)  
            obj.write(message);  
        end  
        if ~isempty(obj.nextLogger)  
            obj.nextLogger.logMessage(level, message);  
        end  
    end  
end  

end

　ConsoleLogger.m

classdef ConsoleLogger < AbstractLogger
methods
function obj=ConsoleLogger(level)
obj.level = level;
end
end
methods(Access = protected)
function write(~,message)
disp("Standard Console::Logger: " + message);
end
end
end

　FileLogger.m

classdef FileLogger < AbstractLogger
    methods
        function obj=FileLogger(level)
            obj.level = level;
        end
    end
    methods(Access = protected)
        function write(~,message)
            disp("File Console::Logger: " + message);
        end
    end   
end

　ErrorLogger.m

classdef ErrorLogger < AbstractLogger
methods
function obj=ErrorLogger(level)
obj.level = level;
end
end
methods(Access = protected)
function write(~,message)
disp("Error Console::Logger: " + message);
end
end
end

　测试代码：

errorLogger = ErrorLogger(AbstractLogger.ERROR);
fileLogger = FileLogger(AbstractLogger.DEBUG);
consoleLogger = ConsoleLogger(AbstractLogger.INFO);

errorLogger.setNextLogger(fileLogger);
fileLogger.setNextLogger(consoleLogger);

loggerChain = errorLogger;
loggerChain.logMessage(AbstractLogger.INFO, "This is an information.");
loggerChain.logMessage(AbstractLogger.DEBUG, "This is a debug level information.");
loggerChain.logMessage(AbstractLogger.ERROR, "This is an error information.");