Missing artifact net.sf.json-lib

1. Error reported: Missing artifact net.sf.json-lib:json-lib:jar:2.4:compile

<dependency>
  <groupId>net.sf.json-lib</groupId>
  <artifactId>json-lib</artifactId>
  <version>2.4</version>
  <classifier>jdk15</classifier>
</dependency>

Reason: json-lib needs to distinguish the jdk version, the configuration in pom.xml should add the tag classifier to specify the jdk version, such as jdk15