Java 使用 slf4j + log4j 写日志

没有SpringBoot等框架的情况下

pom.xml：

<properties>
    <slf4j.version>1.7.26</slf4j.version>
</properties>

<dependencies>

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${slf4j.version}</version>
    </dependency>

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>${slf4j.version}</version>
    </dependency>

</dependencies>

log4j.properties：

# priority: debug<info<warn<error
# you cannot specify every priority with different file for log4j
log4j.rootLogger=info,stdout,info,error
#console
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss.SSS} [%p]  %m%n
#info
log4j.logger.info=info
log4j.appender.info=org.apache.log4j.DailyRollingFileAppender
log4j.appender.info.DatePattern='_'yyyy-MM-dd'.log'
log4j.appender.info.File=logs/info/info.log
log4j.appender.info.Append=true
log4j.appender.info.Threshold=INFO
log4j.appender.info.layout=org.apache.log4j.PatternLayout
log4j.appender.info.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss.SSS} [%p]  %m%n
log4j.appender.info.filter.infoFilter=org.apache.log4j.varia.LevelRangeFilter
log4j.appender.info.filter.infoFilter.LevelMin=INFO
log4j.appender.info.filter.infoFilter.LevelMax=INFO
#error
log4j.logger.error=error
log4j.appender.error=org.apache.log4j.DailyRollingFileAppender
log4j.appender.error.DatePattern='_'yyyy-MM-dd'.log'
log4j.appender.error.File=logs/error/error.log
log4j.appender.error.Append=true
log4j.appender.error.Threshold=ERROR
log4j.appender.error.layout=org.apache.log4j.PatternLayout
log4j.appender.error.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss.SSS} [%p]  %m%n
log4j.appender.error.filter.infoFilter=org.apache.log4j.varia.LevelRangeFilter
log4j.appender.error.filter.infoFilter.LevelMin=ERROR
log4j.appender.error.filter.infoFilter.LevelMax=ERROR

代码：

变量定义：

private static final Logger log = LoggerFactory.getLogger(TestES_Insert.class);

使用：

log.info("创建索引" + indexName + "成功！");

log.error("TestES_Insert 出错", e);