IDEA+Log4j2 设置控制台打印彩色日志

Posted 2021-01-22 darknebula

在Log4j 2.10以前的版本，pattern中配置%highlight属性是可以正常打印彩色日志的

例如：

pattern: "%d{yyyy-MM-dd HH:mm:ss.SSS} %highlight{%-5level} [%t] %highlight{%c{1.}.%M(%L)}: %msg%n"

但是更新到2.10版本以后，控制台中就无法显示彩色日志了，各种级别的日志混杂在一起，难以阅读

通过查阅官方文档，发现在2.10版本以后，Log4j2默认关闭了Jansi（一个支持输出ANSI颜色的类库）

ANSI Styling on Windows
ANSI escape sequences are supported natively on many platforms but are not by default on Windows. To enable ANSI support add the Jansi jar to your application and set property log4j.skipJansi to false. This allows Log4j to use Jansi to add ANSI escape codes when writing to the console.

NOTE: Prior to Log4j 2.10, Jansi was enabled by default. The fact that Jansi requires native code means that Jansi can only be loaded by a single class loader. For web applications this means the Jansi jar has to be in the web container‘s classpath. To avoid causing problems for web applications, Log4j will no longer automatically try to load Jansi without explicit configuration from Log4j 2.10 onward.

可见，配置 log4j.skipJansi 这个全局属性即可。

IDEA中，点击右上角->Edit Configurations，在VM options中添加

-Dlog4j.skipJansi=false

启动应用，显示效果如下：