FlugRost FlugRost - 10 days ago 5
Java Question

Maven can't find Struts2 dependencies

I try to setup a Struts2 project with maven und IntelliJ as IDE.

But maven can't find most of the dependencies. For example:

org.apache.struts:struts2-core:2.5.5


https://mvnrepository.com/artifact/org.apache.struts/struts2-core/2.5.5

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>de.sambohl.brw</groupId>
<artifactId>brw</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<name>brw</name>

<properties>
<struts2.version>2.5.5</struts2.version>
<log4j2.version>${log4j2.version}</log4j2.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

<dependencies>

<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-core</artifactId>
<version>${struts2.version}</version>
</dependency>

<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-config-browser-plugin</artifactId>
<version>${struts2.version}</version>
</dependency>

<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-junit-plugin</artifactId>
<version>${struts2.version}</version>
<scope>test</scope>
</dependency>

<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>${log4j2.version}</version>
</dependency>

<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.5</version>
<scope>test</scope>
</dependency>

<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>

<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jsp-api</artifactId>
<version>2.0</version>
<scope>provided</scope>
</dependency>

</dependencies>

<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.3</version>
<configuration>
<encoding>UTF-8</encoding>
<source>1.5</source>
<target>1.5</target>
</configuration>
</plugin>
<plugin>
<groupId>org.mortbay.jetty</groupId>
<artifactId>jetty-maven-plugin</artifactId>
<version>8.1.16.v20140903</version>
<configuration>
<stopKey>CTRL+C</stopKey>
<stopPort>8999</stopPort>
<systemProperties>
<systemProperty>
<name>xwork.loggerFactory</name>
<value>com.opensymphony.xwork2.util.logging.log4j2.Log4j2LoggerFactory</value>
</systemProperty>
</systemProperties>
<scanIntervalSeconds>10</scanIntervalSeconds>
<webAppSourceDirectory>${basedir}/src/main/webapp/</webAppSourceDirectory>
<webAppConfig>
<descriptor>${basedir}/src/main/webapp/WEB-INF/web.xml</descriptor>
</webAppConfig>
</configuration>
</plugin>
</plugins>
</build>
</project>


error

[INFO] Scanning for projects...
[ERROR] [ERROR] Some problems were encountered while processing the POMs:
[ERROR] Resolving expression: '${log4j2.version}': Detected the following recursive expression cycle in 'log4j2.version': [log4j2.version] @
[ERROR] Resolving expression: '${log4j2.version}': Detected the following recursive expression cycle in 'log4j2.version': [log4j2.version] @
[ERROR] 'dependencies.dependency.version' for org.apache.logging.log4j:log4j-core:jar must be a valid version but is '${log4j2.version}'. @ line 41, column 22
@
[ERROR] The build could not read 1 project -> [Help 1]
[ERROR]
[ERROR] The project de.sambohl.brw:brw:1.0-SNAPSHOT (/Users/philipp/IdeaProjects/brw/pom.xml) has 3 errors
[ERROR] Resolving expression: '${log4j2.version}': Detected the following recursive expression cycle in 'log4j2.version': [log4j2.version] -> [Help 2]
[ERROR] Resolving expression: '${log4j2.version}': Detected the following recursive expression cycle in 'log4j2.version': [log4j2.version] -> [Help 2]
[ERROR] 'dependencies.dependency.version' for org.apache.logging.log4j:log4j-core:jar must be a valid version but is '${log4j2.version}'. @ line 41, column 22
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/ProjectBuildingException
[ERROR] [Help 2] http://cwiki.apache.org/confluence/display/MAVEN/InterpolationCycleException

Process finished with exit code 1

Answer

Your problem is here

<log4j2.version>${log4j2.version}</log4j2.version>

Indeed your error means that "${log4j2.version}" is not a valid version.

You are supposed to set explicitly a version of log4j2 instead of "${log4j2.version}" for example you could use 2.7 if you want to use the latest version (which is also the version on which org.apache.struts:struts2-core:2.5.5 relies), see the list of existing versions here.

So try this

<log4j2.version>2.7</log4j2.version>