今天在写一个demo时报了以下错误
SLF4J: Class path contains multiple SLF4J bindings. SLF4J: Found binding in [jar:file:/D:/chengxu/mavenRepository/org/slf4j/slf4j-log4j12/1.7.25/slf4j-log4j12-1.7.25.jar!/org/slf4j/impl/StaticLoggerBinder.class] SLF4J: Found binding in [jar:file:/D:/chengxu/mavenRepository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar!/org/slf4j/impl/StaticLoggerBinder.class] SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation. SLF4J: Actual binding is of type [org.slf4j.impl.Log4jLoggerFactory] log4j:WARN No appenders could be found for logger (us.codecraft.webmagic.scheduler.QueueScheduler). log4j:WARN Please initialize the log4j system properly. log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
一看就是 SLF4J 依赖冲突,查看一下有哪些包依赖了 SLF4J
使用命令:
mvn dependency:tree -Dverbose -Dincludes=org.slf4j
输出如下
[INFO] --- maven-dependency-plugin:3.0.1:tree (default-cli) @ stock --- [INFO] Verbose not supported since maven-dependency-plugin 3.0 [INFO] com.huitong:stock:pom:1.0-SNAPSHOT [INFO] +- us.codecraft:webmagic-core:jar:0.7.3:compile [INFO] | +- org.slf4j:slf4j-api:jar:1.7.25:compile [INFO] | \- org.slf4j:slf4j-log4j12:jar:1.7.25:compile [INFO] \- org.springframework.boot:spring-boot-starter-aop:jar:2.0.0.RELEASE:compile [INFO] \- org.springframework.boot:spring-boot-starter:jar:2.0.0.RELEASE:compile [INFO] \- org.springframework.boot:spring-boot-starter-logging:jar:2.0.0.RELEASE:compile [INFO] \- org.slf4j:jul-to-slf4j:jar:1.7.25:compile
可以看到webmagic-core 和 springboot-starter-aop 相冲突,所以在 pom 文件修改
<dependency> <groupId>us.codecraft</groupId> <artifactId>webmagic-core</artifactId> <version>0.7.3</version> <exclusions> <exclusion> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> </exclusion> <exclusion> <groupId>log4j</groupId> <artifactId>log4j</artifactId> </exclusion> </exclusions> </dependency>
再运行即可