如何使用 Spring Boot 设置 log4j2 自定义附加程序？

Question

我在为我的 spring 引导应用程序创建自定义附加程序时面临挑战。抛出以下异常：

2019-11-08 10:33:27,897 main ERROR Unable to locate plugin type for 
mycustomhandlerclass
2019-11-08 10:33:27,961 main ERROR Unable to locate plugin for 
mycustomhandlerclass
2019-11-08 10:33:27,961 main ERROR Unable to invoke factory method in 
class org.apache.logging.log4j.core.config.AppendersPlugin for element 
Appenders: java.lang.NullPointerException java.lang.NullPointerException

Spring 引导版本：2.1.7

Maven插件版本：3.1.1

Mycustomhandlerclass.java:

import java.io.Serializable;

import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.Layout;
import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.appender.AbstractAppender;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
import org.apache.logging.log4j.core.config.plugins.PluginElement;
import org.apache.logging.log4j.core.config.plugins.PluginFactory;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

@Plugin(category = "Core", name = "Mycustomhandlerclass", elementType = "appender")
public class Mycustomhandlerclass extends AbstractAppender {

    private final Logger logger = LogManager.getLogger(getClass().getName());

    @SuppressWarnings("deprecation")
    protected AmtAppender(String name, Filter filter, Layout<? extends Serializable> layout, boolean ignoreExceptions) {
        super(name, filter, layout,ignoreExceptions);
        // TODO Auto-generated constructor stub
    }

    @PluginFactory
    public static Mycustomhandlerclass createAppender(@PluginAttribute("name") String name, @PluginAttribute("ignoreExceptions") boolean ignore, @PluginElement("Filter") Filter filter, @PluginElement("Layout") Layout<? extends Serializable> layout) { 
        return new Mycustomhandlerclass(name, filter, layout, ignore);    
    }

    @Override
    public void append(LogEvent event) {
        // TODO Auto-generated method stub
        logger.info("Entered CustomAppender");
    }

}

log4j2.properties:

name=PropertiesConfig
appenders = file, errorFile, customAppender
property.filename = D:/logdestinationfolder

appender.file.type = RollingFile
appender.file.name = OUTFILE
appender.file.fileName = ${filename}/console.log
appender.file.filePattern = ${filename}/console%d{yyyy-MM-dd}.log
appender.file.layout.type = PatternLayout
appender.file.layout.pattern = %-5p %d{dd-MM-yyyy HH:mm:ss} %t  %c{1}   %m%n
appender.file.policies.type = Policies
appender.file.policies.time.type = TimeBasedTriggeringPolicy
appender.file.policies.time.interval = 1
appender.file.strategy.type=DefaultRolloverStrategy
appender.file.strategy.max=5

appender.errorFile.type = RollingFile
appender.errorFile.name = ERROROUTFILE
appender.errorFile.fileName = ${filename}/error.log
appender.errorFile.filePattern = ${filename}/error%d{yyyy-MM-dd}.log
appender.errorFile.layout.type = PatternLayout
appender.errorFile.layout.pattern = %-5p %d{dd-MM-yyyy HH:mm:ss} %t %c{1}   %M() :: %L  %m%n
appender.errorFile.policies.type = Policies
appender.errorFile.policies.time.type = TimeBasedTriggeringPolicy
appender.errorFile.policies.time.interval = 1
appender.errorFile.strategy.type=DefaultRolloverStrategy
appender.errorFile.strategy.max=5
appender.errorFile.filter.1.type=ThresholdFilter
appender.errorFile.filter.1.onMatch=ACCEPT
appender.errorFile.filter.1.level=ERROR

appender.customAppender.type = Mycustomhandlerclass
appender.customAppender.name = CUSTOMAPPENDER
appender.customAppender.filter.1.type=ThresholdFilter
appender.customAppender.filter.1.onMatch=ACCEPT
appender.customAppender.filter.1.level=WARN

rootLogger.level = ERROR

loggers=appLogger

logger.appLogger.name = com.solartis
logger.appLogger.level = DEBUG
logger.appLogger.appenderRefs=errorFile,file,customAppender
logger.appLogger.appenderRef.errorFile.ref = ERROROUTFILE
logger.appLogger.appenderRef.file.ref = OUTFILE
logger.appLogger.appenderRef.customAppender.ref = CUSTOMAPPENDER

注意：删除 log4j2.properties 中的 appender 引用后，日志将写入 log4j2.properties 中提到的路径中的文件。因此，问题在于 customappender 集成。

Answer 1

您必须在 log4j.properties 中添加您的 appender class 的包，例如包 = org.home.appenders

Answer 2

错误在这段代码中：-

protected AmtAppender(String name, Filter filter, Layout<? extends Serializable> layout, boolean ignoreExceptions) {
    super(name, filter, layout,ignoreExceptions);
    // TODO Auto-generated constructor stub
}

什么是AmtAppender？构造函数名称应与 class 名称相同。您需要以这种方式提供构造函数：-

@SuppressWarnings("deprecation")
protected MyCustomAppender(String name, Filter filter)
{

    super(name, filter, null);
}

如何使用 Spring Boot 设置 log4j2 自定义附加程序？

How to setup a log4j2 custom appender with Spring Boot?

log4j

appender

log4j2

spring-boot