在log4j2中打印intLevel

Answer 1

听起来像是希望记录日志级别的整数值而不是名称，并且不希望使用patternlayout的level参数的标记特性。

一个可能的解决方案是创建一个自定义的查找,下面是一些示例代码：

package example;

import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.lookup.StrLookup;

@Plugin(name = "level", category = "Lookup")
public class LevelLookup implements StrLookup{
    /**
     * Lookup the value for the key.
     * @param key  the key to be looked up, may be null
     * @return The value for the key.
     */
    public String lookup(String key) {
        return null;
    }


    /**
     * Lookup the value for the key using the data in the LogEvent.
     * @param event The current LogEvent.
     * @param key  the key to be looked up, may be null
     * @return The value associated with the key.
     */
    public String lookup(LogEvent event, String key) {
        return String.valueOf(event.getLevel().intLevel());
    }
}

下面是使用新查找的示例配置-注意${level:}:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] ${level:} %logger{36} - %msg%n" />
        </Console>
    </Appenders>

    <Loggers>
        <Root level="debug">
            <AppenderRef ref="Console" />           
        </Root>
    </Loggers>
</Configuration>

下面是一些执行日志记录的示例代码：

package example;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class SomeClass {

    private static final Logger log = LogManager.getLogger();   

    public static void main(String[] args){
        log.debug("This is some debug!");
        log.info("Here's some info!");
        log.error("Some erorr happened!");
    }
}

最后是输出：

22:49:29.438 [main] 500 example.SomeClass - This is some debug!
22:49:29.440 [main] 400 example.SomeClass - Here's some info!
22:49:29.440 [main] 200 example.SomeClass - Some erorr happened!

希望这有帮助！