Error importing Maven project in eclipse

Question

I have a problem which I do not know how to solve. I want to import a maven project to eclipse. However when I am doing so I am getting following error from eclipse:

But when I am doing "mvn install" in the terminal, I am able to successfully build the project. Here is the pom.xml file:

<?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.thinkaurelius.titan</groupId>
    <artifactId>titan-web-example</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>war</packaging>

    <description>
        This is a simple web app example.
    </description>
    <licenses>
        <license>
            <name>The Apache Software License, Version 2.0</name>
            <url>http://www.apache.org/licenses/LICENSE-2.0.txt</url>
        </license>
    </licenses>

    <properties>
        <spring.version>4.0.3.RELEASE</spring.version>
        <titan.version>1.0.0</titan.version>
    </properties>

    <dependencies>

        <dependency>
            <groupId>com.thinkaurelius.titan</groupId>
            <artifactId>titan-cassandra</artifactId>
            <version>${titan.version}</version>
            <exclusions>
                <!-- These don't play well w/ the web classesthatrunthings deps below -->
                <exclusion>
                    <groupId>org.mortbay.jetty</groupId>
                    <artifactId>servlet-api</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>javax.servlet</groupId>
                    <artifactId>servlet-api</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>com.thinkaurelius.titan</groupId>
            <artifactId>titan-es</artifactId>
            <version>${titan.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.tinkerpop</groupId>
            <artifactId>gremlin-groovy</artifactId>
            <version>3.0.0-incubating</version>
        </dependency>


        <!-- Web App -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.jboss.resteasy</groupId>
            <artifactId>jaxrs-api</artifactId>
            <version>2.2.1.GA</version>
        </dependency>

        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-server</artifactId>
            <version>1.18.1</version>
        </dependency>

        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-json</artifactId>
            <version>1.18.1</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <!-- Jersey -->
        <dependency>
            <groupId>com.sun.jersey.contribs</groupId>
            <artifactId>jersey-spring</artifactId>
            <version>1.18.1</version>
            <exclusions>
                <!-- oh maven you crazy old bird! -->
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-core</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-web</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-beans</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-context</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework</groupId>
                    <artifactId>spring-aop</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <!-- Jetty Embedded App Container -->
        <!-- You only need this if you want to run the web app in the embedded jetty container using the RunApp class -->
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-server</artifactId>
            <version>9.2.0.v20140526</version>
        </dependency>

        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-webapp</artifactId>
            <version>9.2.0.v20140526</version>
        </dependency>

        <!-- Util -->
        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
            <version>2.4</version>
        </dependency>

        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.2.4</version>
        </dependency>

        <!-- Groovy GMaven -->
        <dependency>
            <groupId>org.codehaus.gmaven</groupId>
            <artifactId>gmaven-plugin</artifactId>
            <version>1.4</version>
        </dependency>

    </dependencies>

    <build>
        <finalName>titan-web-example</finalName>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.4</version>
            </plugin>

            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.codehaus.gmaven</groupId>
                <artifactId>gmaven-plugin</artifactId>
                <version>1.4</version>
                <configuration>
                    <providerSelection>1.8</providerSelection>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>generateStubs</goal>
                            <goal>compile</goal>
                            <goal>generateTestStubs</goal>
                            <goal>testCompile</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>

        </plugins>
    </build>

</project>

It looks like gmaven has a problem in eclipse, but I do not know how to solve that.

Answer 1

The way Eclipse handles Maven projects is currently through the m2e plugin.

m2e does not invoking Maven underneath, but parses the pom.xml files and for each plugin mentioned invoke code explicitly written to behave identically inside m2e as the plugin. This is what a "connector" is.

If a connector is not available for a given plugin (so m2e could emulate it for you) you see this error. This is unfortunately not uncommon for the more rare plugins.

You must investigate to see if it is enough for m2e to be able to present enough of the project to allow you to work anyway, and then just do real builds from the command line.

You may also consider using another free IDE for such a troublesome project. I know that IntelliJ works with almost any pom.xml file, and am told that Netbeans can too.