Gson object error during Junit using (powermock/mockito)

[sallewar1]

LocalPageResponse localPageResponse = createLocalPageService.createLocalPage(filePath);
Gson finalResponse = new Gson();
response.getWriter().print(finalResponse.toJson(localPageResponse));

List<String> outputLogs = new ArrayList<>();

this is piece of code from servlet , while writing test class for same , not able to pass this "Gson finalResponse = new Gson()" line od code and showing error like

java.lang.NoClassDefFoundError: com/google/gson/internal/bind/JsonTreeReader

at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at javassist.runtime.Desc.getClassObject(Desc.java:43)
at javassist.runtime.Desc.getClassType(Desc.java:152)
at javassist.runtime.Desc.getType(Desc.java:122)
at javassist.runtime.Desc.getType(Desc.java:78)

......

I am trying to execute the test class, has anyone faced the same issue and if yes, how was it resolved?

[Lokesh_Vajrala · Accepted solution]

The version of Gson dependency - com.google.gson in code may need to be updated or add the dependency if missing with the test scope. The error says that the JsonTreeReader class is not available in the classpath to execute the test.

There is this thread clearly explains on the NoClassDefFoundError - https://stackoverflow.com/questions/17973970/how-can-i-solve-java-lang-noclassdeffounderror 

[Saravanan_Dharmaraj]

What is  gson dependency version in your parent pom? 

<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.8.5</version>
    <scope>provided</scope>
</dependency>

Try to update the gson to this or higher and see if its working?