使用maven构建项目，如果项目模块比较多的话，有可能会出现jar文件冲突，如果不排查重复jar包项目就会出现编译问题。
我们排查jar文件冲突可以使用maven自带的命令，将所有依赖的jar文件打印出来，或者打印至txt文件中进行排查。
maven打印依赖包信息至文件中
在项目模块目录下使用如下命令，将依赖信息打印至tree.txt文件中。
mvn dependency:tree -Dverbose > tree.txt
搜索文件中的"conflict"可查找冲突jar文件
[INFO] +- io.springfox:springfox-swagger2:jar:2.6.1:compile
[INFO] | +- io.swagger:swagger-annotations:jar:1.5.10:compile
[INFO] | +- io.swagger:swagger-models:jar:1.5.10:compile
[INFO] | | +- com.fasterxml.jackson.core:jackson-annotations:jar:2.8.1:compile (version managed from 2.4.5)
[INFO] | | +- (org.slf4j:slf4j-api:jar:1.7.21:compile - version managed from 1.7.10; omitted for duplicate)
[INFO] | | \- (io.swagger:swagger-annotations:jar:1.5.10:compile - omitted for duplicate)
[INFO] | +- io.springfox:springfox-spi:jar:2.6.1:compile
[INFO] | | \- io.springfox:springfox-core:jar:2.6.1:compile
[INFO] | | +- (com.google.guava:guava:jar:18.0:compile - omitted for duplicate)
[INFO] | | +- (com.fasterxml:classmate:jar:1.3.1:compile - omitted for duplicate)
[INFO] | | +- (org.slf4j:slf4j-api:jar:1.7.21:compile - version managed from 1.6.3; omitted for duplicate)
[INFO] | | +- (org.springframework.plugin:spring-plugin-core:jar:1.2.0.RELEASE:compile - omitted for duplicate)
[INFO] | | \- (org.springframework.plugin:spring-plugin-metadata:jar:1.2.0.RELEASE:compile - omitted for duplicate)
[INFO] | +- io.springfox:springfox-schema:jar:2.6.1:compile
[INFO] | | +- (io.springfox:springfox-core:jar:2.6.1:compile - omitted for duplicate)
[INFO] | | \- (io.springfox:springfox-spi:jar:2.6.1:compile - omitted for duplicate)
[INFO] | +- io.springfox:springfox-swagger-common:jar:2.6.1:compile
[INFO] | | +- (io.swagger:swagger-annotations:jar:1.5.10:compile - omitted for duplicate)
[INFO] | | +- (io.swagger:swagger-models:jar:1.5.10:compile - omitted for duplicate)
[INFO] | | +- (io.springfox:springfox-spi:jar:2.6.1:compile - omitted for duplicate)
[INFO] | | +- (io.springfox:springfox-schema:jar:2.6.1:compile - omitted for duplicate)
[INFO] | | +- (io.springfox:springfox-spring-web:jar:2.6.1:compile - omitted for duplicate)
[INFO] | | +- (com.google.guava:guava:jar:18.0:compile - omitted for duplicate)
[INFO] | | +- (com.fasterxml:classmate:jar:1.3.1:compile - omitted for duplicate)
[INFO] | | +- (org.slf4j:slf4j-api:jar:1.7.21:compile - version managed from 1.7.10; omitted for duplicate)
[INFO] | | +- (org.springframework.plugin:spring-plugin-core:jar:1.2.0.RELEASE:compile - omitted for duplicate)
[INFO] | | \- (org.springframework.plugin:spring-plugin-metadata:jar:1.2.0.RELEASE:compile - omitted for duplicate)
[INFO] | +- io.springfox:springfox-spring-web:jar:2.6.1:compile
[INFO] | | +- (com.google.guava:guava:jar:18.0:compile - omitted for duplicate)
[INFO] | | +- (com.fasterxml:classmate:jar:1.3.1:compile - omitted for duplicate)
[INFO] | | +- (org.slf4j:slf4j-api:jar:1.7.21:compile - version managed from 1.7.10; omitted for duplicate)
[INFO] | | +- (org.springframework.plugin:spring-plugin-core:jar:1.2.0.RELEASE:compile - omitted for duplicate)
[INFO] | | +- (org.springframework.plugin:spring-plugin-metadata:jar:1.2.0.RELEASE:compile - omitted for duplicate)
[INFO] | | \- (io.springfox:springfox-spi:jar:2.6.1:compile - omitted for duplicate)
[INFO] | +- (com.google.guava:guava:jar:18.0:compile - omitted for ---<conflict 关键字>--- with 15.0)
[INFO] | +- com.fasterxml:classmate:jar:1.3.1:compile
[INFO] | +- org.slf4j:slf4j-api:jar:1.7.21:compile
