如何在log4cplus中添加自定义过滤器？ [英] How do I add a custom filter in log4cplus?

问题描述

这是此问题的后续追踪条件日志。

This is a followup to this question on conditional logging.

我在log4cplus测试目录中找到了如何在属性文件中配置过滤器的示例（所以使用XML是不必要的）我创建了自己的过滤器，但我有麻烦使用它。以下是我所做的更改：

I found examples in the log4cplus test directory of how to configure filters in the properties file (so using the XML is unnecessary) I have created my own filter but I am having trouble using it. Here are the changes I made:

在spi / filter.h中：

In spi/filter.h:

class LOG4CPLUS_EXPORT InstructionNumberFilter : public Filter {
    public:
      // ctors
        InstructionNumberFilter();
        InstructionNumberFilter(const log4cplus::helpers::Properties& p);

        /**
         * Returns {@link #NEUTRAL} is there is no string match.
         */
        virtual FilterResult decide(const InternalLoggingEvent& event) const;

    private:
      // Methods
        LOG4CPLUS_PRIVATE void init();

      // Data
        /** Do we return ACCEPT when a match occurs. Default is <code>true</code>. */
        uint instructionNumberToMatch;

};

在spi / filter.cxx中：

In spi/filter.cxx:

InstructionNumberFilter::InstructionNumberFilter()
{
    init();
}

InstructionNumberFilter::InstructionNumberFilter(const helpers::Properties& properties)
{
    init();
    properties.getUInt(instructionNumberToMatch, LOG4CPLUS_TEXT("InstructionNumber"));    
}    

void
InstructionNumberFilter::init()
{
    instructionNumberToMatch = 0;
}    

FilterResult
InstructionNumberFilter::decide(const InternalLoggingEvent& event) const
{
    const uint currentInstructionNumber = 4; // TODO get number from MDC

    if( currentInstructionNumber == instructionNumberToMatch ){
        return ACCEPT;
    }

    return NEUTRAL;
}

在factory.cxx：

In factory.cxx:

LOG4CPLUS_REG_FILTER (reg3, InstructionNumberFilter);

在属性文件中：

# Set up logging to standard output stream.

log4cplus.appender.AP1=log4cplus::ConsoleAppender
log4cplus.appender.AP1.layout=log4cplus::PatternLayout
log4cplus.appender.AP1.layout.ConversionPattern=Rabble %-5p MDC(instructionNumber):%-10X{instructionNumber} [%d{%Q}](%l): %m

log4cplus.appender.AP1.filters.1=log4cplus::spi::InstructionNumberFilter
log4cplus.appender.AP1.filters.1.InstructionNumberToMatch=4
log4cplus.appender.AP1.filters.2=log4cplus::spi::DenyAllFilter

运行时出现错误：

log4cplus:ERROR Appender::ctor()- Cannot find FilterFactory: log4cplus::spi::InstructionNumberFilter

我试图将所有我的更改基于StringMatchFilter的实现。我缺少一些我需要做的事情，让我的过滤器被识别？

I tried to base all my changes on the implementation of the StringMatchFilter. Am I missing something else I need to do to get my filter to be recognized?

感谢您的帮助。

推荐答案

错误是由于从log4cplus构建的库错误定位的结果。

The error was a result of mislocating the libraries built from log4cplus.

因此，上述示例是在log4cplus中实现自定义过滤器的方法。除非有任何对象，我会离开这里，因为在网络上有很少的log4cplus过滤器的例子。

So, the example above is the way to implement a custom filter in log4cplus. Unless anyone objects I will leave this here as there are very few examples of log4cplus filters on the web.

这篇关于如何在log4cplus中添加自定义过滤器？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！