Getting java.lang.ClassNotFoundException: com.google.gson.Gson for maven project

Question

I am new to maven.I am using apache-maven-3.2.2 for building my project.Its simple project which will received json data from client side and on server side it will convert this json data to its analogous java class.For conversion of json to java format we are using google's Gson library.Without maven my project is running properly.but when I converted it to maven then I got the following error:

   Caused by: java.lang.NoClassDefFoundError: com/google/gson/Gson
   at com.edfx.tsn.web.controller.DataController.transferData(DataController.java:51) [classes:]
   at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_17]
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_17]
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_17]
   at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_17]
   at org.apache.el.parser.AstValue.invoke(AstValue.java:262) [jbossweb-7.0.13.Final.jar:]
   at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:278) [jbossweb-7.0.13.Final.jar:]
   at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105) [jsf-impl-2.1.7-jbossorg-2.jar:]
   at javax.faces.event.MethodExpressionActionListener.processAction(MethodExpressionActionListener.java:148) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
   ... 22 more

From the error its pretty clear that its unable to Gson jar.

Now below is my pom.xml file

 <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>TestJSON</groupId>
   <artifactId>TestJSON</artifactId>
   <version>0.0.1-SNAPSHOT</version>
   <name>TestJSON</name>
  <build>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.1</version>
            <configuration>
                <source>1.7</source>
                <target>1.7</target>
            </configuration>
        </plugin>
    </plugins>
</build>
<dependencies>
    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.2.4</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.0.1</version>
    </dependency>
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-api</artifactId>
        <version>2.2.6</version>
    </dependency>
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-impl</artifactId>
        <version>2.2.6</version>
    </dependency>
  </dependencies>
   <packaging>war</packaging>
  </project>

I am not getting any error at compile time and my project is getting deployed properly.I am using Jboss7 as.But I am getting this error at runtime when my actionListener method is getting invoked.

I have already gone through couple of links in stackoverflow specially the below one

GSON is not being imported into the maven pproject

but it didn't serve my purpose.Can anyone provide any solution to this.Thanks in advance.

Answer 1

1. go to your repo location and check if the jar is properly downloaded.
2. unpack your WAR and check if the jar is actually available in it.
3. althoug your maven dependency looks fine, but just try using this: 
    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.3</version>
    </dependency>
4. Make sure you do a mvn clean:install -P from command prompt location of the project.
5. I tried with the same dependency and it works fine with JBOSS too.

Answer 2

In Gradle I have added following and error has gone. I am trying to build serenity-BDD project

compile group: 'com.google.code.gson', name: 'gson', version: '2.8.2'

My dependencies are following:

   dependencies {

    def SERENITY_VERSION = "1.6.7-rc.1"
    compile 'net.serenity-bdd:serenity-core:' + SERENITY_VERSION
    compile 'net.serenity-bdd:serenity-rest-assured:' + SERENITY_VERSION
       compile group: 'net.serenity-bdd', name: 'serenity-cucumber', version: '1.1.36'

    compile group: 'info.cukes', name: 'cucumber-core', version: '1.2.5'
    testCompile 'org.assertj:assertj-core:3.1.0'
    testCompile 'com.googlecode.lambdaj:lambdaj:2.3.3'
    testCompile 'io.codearte.jfairy:jfairy:0.5.3'
    compile 'net.serenity-bdd:serenity-screenplay:' + SERENITY_VERSION
    compile 'net.serenity-bdd:serenity-screenplay-webdriver:' + SERENITY_VERSION
    compile 'net.serenity-bdd:browse-the-web:1.1.34'
    testCompile 'net.serenity-bdd:serenity-junit:' + SERENITY_VERSION
   '3.5.3'
    testCompile 'org.slf4j:slf4j-simple:1.7.12'
    compile group: 'com.google.code.gson', name: 'gson', version: '2.8.2'}