my maven project has multiple maven modules. Two of those modules (product and feature) are dependent on each other. When I include the modules as dependencies in the pom files, an ! mark appears on the modules. On running maven install I get this error.
The projects in the reactor contain a cyclic reference: Edge between
'Vertex{label='com.catalog:feature:0.0.1-SNAPSHOT'}' and
'Vertex{label='com.catalog:product:0.0.1-SNAPSHOT'}' introduces to
cycle in the graph com.catalog:product:0.0.1-SNAPSHOT -->
com.catalog:feature:0.0.1-SNAPSHOT --> com.catalog:product:0.0.1-
SNAPSHOT @
Without adding the dependencies Product can't access functions defined in Feature module and vice versa.
The parent pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.catalog</groupId>
<artifactId>catalog</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>pom</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.2.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.hibernate.javax.persistence</groupId>
<artifactId>hibernate-jpa-2.1-api</artifactId>
<version>1.0.0.Final</version>
</dependency>
<dependency>
<groupId>org.osgi</groupId>
<artifactId>org.osgi.core</artifactId>
<version>4.3.1</version>
</dependency>
<dependency>
<groupId>org.osgi</groupId>
<artifactId>org.osgi.enterprise</artifactId>
<version>4.2.0</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>5.0.0.Final</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.4.1.Final</version>
</dependency>
<dependency>
<groupId>javassist</groupId>
<artifactId>javassist</artifactId>
<version>3.12.1.GA</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.jayway.jsonpath</groupId>
<artifactId>json-path</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>6.0.6</version>
</dependency>
</dependencies>
<modules>
<module>category</module>
<module>resource</module>
<module>hibernate</module>
<module>product</module>
<module>helper</module>
<module>feature</module>
</modules>
Product module pom.xml
<?xml version="1.0"?>
<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd"
xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.catalog</groupId>
<artifactId>catalog</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<artifactId>product</artifactId>
<name>product</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>com.catalog</groupId>
<artifactId>hibernate</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.catalog</groupId>
<artifactId>category</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.catalog</groupId>
<artifactId>helper</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.catalog</groupId>
<artifactId>feature</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
</dependencies>
</project>
Feature module pom.xml
<?xml version="1.0"?>
<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd"
xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.catalog</groupId>
<artifactId>catalog</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<groupId>com.catalog</groupId>
<artifactId>feature</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>feature</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>com.catalog</groupId>
<artifactId>hibernate</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>com.catalog</groupId>
<artifactId>product</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
</dependencies>
</project>
Refactor your modules. Basically everything which is needed in both modules should go into a common dependency. You cannot have cycles in your dependency tree, it just won't work.