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Kotlin/KAPT Generated Kotlin class is not recognized as class member, but it does inside of methods

I have written an annotation processor that generates a builder class for my classes annotated with #DataBuilder
#Target(AnnotationTarget.CLASS)
#Retention(AnnotationRetention.SOURCE)
annotation class DataBuilder
My classes annotated with this annotation are located in the com.my.package.model package and the generated builder class is also located in the same package com.my.package.model but in the generated directory of course build/generated/source/kapt/debug/com/my/package/model/MyModelBuilder.kt, I can use these generated classes fine inside of my model classes(written in Kotlin)
BUT I can NOT use the generated MyModelBuilder Kotlin class inside of a java class as a class member
package com.my.package.home;
import com.my.package.model.MyModelBuilder;
public class Home {
MyModelBuilder builder; // <=== AS recognizes the class, but I'm having an compilation issue
}
Android Studio recognizes the class, but I’m having this compilation issue
com/my/package/home/Home.java:4: error: cannot find symbol
MyModelBuilder builder;
^
symbol: class MyModelBuilder
location: class Home
it’s weird because I can use this generated builder class only inside of methods, this code compiles fine:
package com.my.package.home;
import com.my.package.model.MyModelBuilder;
public class Home {
public void hello() {
MyModelBuilder builder;
}
}
could somebody here help me to understand this behavior and how to fix this? In advance, thanks!
UPDATE
I just created this repo with the necessary code to replicate the issue
https://github.com/epool/HelloKapt
The project works fine after cloning and running, to replicate the issue please un-comment this line https://github.com/epool/HelloKapt/blob/master/app/src/main/java/com/nearsoft/hellokapt/app/MainActivity.java#L13
Note: If I convert my MainActivity.java class to Kotlin(MainActivity.kt) the issues is NOT reproducible and works fine, but I don’t want to do so due to some project limitations so far
Kotlin Issue: https://youtrack.jetbrains.net/issue/KT-24591

Looking at your Github project, I notice that you don't declare a dependency on kotlin-stdlib-jdk7 in the app module. When I build the module, compiler emits the following warnings:
warning: unknown enum constant AnnotationTarget.CLASS
reason: class file for kotlin.annotation.AnnotationTarget not found
warning: unknown enum constant AnnotationRetention.SOURCE
reason: class file for kotlin.annotation.AnnotationRetention not found
warning: unknown enum constant AnnotationTarget.CLASS
reason: class file for kotlin.annotation.AnnotationTarget not found
Since kotlin-stdlib-jdk7 is declared as implementation in the annotations module, the app module doesn't see it as a transitive dependency, that might be the reason why compilation fails. To fix it, you should probably declare the correct dependency in the app module, or at least use apiElements scope for kotlin-stdlib-jdk7 in annotations.
The fact that the IDE doesn't notify you that compilation failed might be a tools bug, but there's definitely no underlying Kotlin compiler issue.

StrutsTestCase implementation - Compilation error

I am using Struts 2 to create a web application. I am using StrutsTestCase for Junit test case to test the Action class. I have imported struts2-junit-plugin-2.3.4.jar as I am using struts2-core-2.3.4.jar. Inside the testcase method, when i tried to set the request parameters, request variable is not available for use. it is showing compilation error. I am getting 'request cannot be resolve' error. In my test class i am extending StrutsTestCase which has request as protected parameter. But it is not available inside extended method.
My test action looks like this:
import org.apache.struts2.StrutsTestCase;
public class WallPlanningActionTest extends StrutsTestCase {
public void testList() {
request.setParameter("salesOrg",1);
}

You can only get compilation errors if StrutsTestCase which your class is extended is not org.apache.struts2.StrutsTestCase. You could optimize the imports or just use FQCN.
public class WallPlanningActionTest extends org.apache.struts2.StrutsTestCase {

For future readers:
I had the same problem - the protected request field was not accessible. The problem was that i hadn't add the spring libraries. StrutsTestCase uses spring-core-x.y.z and spring-test-x.y.z. It is depended on them an i couldn't find a way to use the unit tests without them.
Other dependencies could be found by opening the struts-junit-plugin jar (as archive). Open the META-INF folder and in there you will find DEPENDENCIES file with a list of all dependencies.
Hope this helps someone.

com.liferay.portlet.ActionResponseImpl cannot be cast to com.liferay.portlet.ActionResponseImpl

I tried to cast Action response like this:
private void mappingMethod(ActionResponse response) {
ActionResponseImpl actionResponseImpl = (ActionResponseImpl)response;
...}
In debugging on "Expression Evaluation" window I can see the type of "responce" is ActionResponseImpl, and cast does not cause exception. But on runtime I have this exeption:
java.lang.ClassCastException: com.liferay.portlet.ActionResponseImpl cannot be cast to com.liferay.portlet.ActionResponseImpl
Please tell me what is the problem.
P.S.: In PortalImpl class, the copyRequestParameters method has same string, but here it's working....

It would do you good if you refrained from using classes from portal-impl.jar in your custom plugin portlet.
ActionResponseImpl is a class in the portal-impl.jar. So if you can give a use-case as to why you are planning to use this class, then we can suggest alternative.

You have ActionResponseImpl twice on the classpath - what jars from Liferay did you include in your project? As Prakash mentions, it's portal-impl.jar, which you can not have in a plugin.
What the ClassCastException wants to tell you is that your class extends one implementation of ActionResponseImpl, but the runtime environments expects it to be another implementation - they might be identical, but as they are loaded from two different sources, the classloader cannot refer one to another superclass than it extends.

I saw this issue, when I call a method using Ajax from XHTML page. I modified my method to return simple string and removed the code that tries to modify the actionResponseImpl and that resolved the issue.

This type of errors are produced by different classloaders. A class is identified by their fully qualified class name AND its Classloader. So if you embedd portal-impl in your portlet; the action is going to receive an ActionResponseImpl instance from the portal classloader and is trying to cast this one to a class of your portlet class loader .
see more: http://www.javaspecialists.eu/archive/Issue018.html

NoClassDefFoundError exception in my thread

I get this error:
Exception in thread "http-server" java.lang.NoClassDefFoundError: org/w3c/jigmonitor/ReplyServer
but I don't undestand why. Could someone explain why does this happen?
This is the class that causes the problem:
public class ReplyServer implements Serializable
{
public ReplyServer()
{
super();
}
}

It looks like the class you're defining isn't being found by something that's trying to load it. In my experience this is caused by one of three problems:
Your package declaration for the class is not correct. In this case something on the http-sever thread is expecting your class to be declared in the package org.w3c.jigmonitor.
Your source file is not located in the correct directory. In this case, your source file should be located in a directory structure like "org/w3c/jigmonitor/", providing that's the package you actually want.
The path of the compiled class for ReplyServer is not in the classpath of your JVM. You can check this by looking at the classpath used to start your JVM and seeing if the class is actually there or not. In most generic setups servlet setups there will be a "WEB-INF/classes" folder for you to go poke around in.
Good luck!
(The link David posted gives a ton of information on this type of issue and the possible causes. I would recommend tucking that away for later)

Xcode cannot find a java class which I'm trying to extend

I'm working on a Java project which was written by someone else. This person made a hierarchy of folders inside the 'src' folder. I've added a new java class into one of those folders and defined it as 'XmlFile.java'.
Then, I'm trying to have it extend a previously written class 'GenericFile.java' by writing
package //Same package GenericFile is in
public class XmlFile extends GenericFile
{
...
}
When I try to compile the project it gives me the error
Cannot find symbol
and refers me to the line
public class XmlFile extends GenericFile
if I take out
extends GenericFile
everything compiles great.
I also notice after adding the new file (XmlFile.java) I cannot delete it (the option in Edit->Delete is not selectable for that file, or for any files/folders created by the person from whom I got the project).
Is there some sort of permission issue here or some hidden scope issue caused by the permissions being strange or what?
Please help me
Cheers,
WhiteTiger

I admit I am not an expert enough to figure out "Cannot find symbol" from a Java compiler, but since there is no other answer, here is a sneaky idea -
If GenericFile is a working and useful abstract class, there has to be at least one other class (hopefully working) that extends it. Since you have the source code, find out one such file, copy it to XmlFile.java, edit it to change the constructor name to XmlFile and try to compile it. If it compiles, start from there. If not, you will know where the problem lies.
Just trying to help! Good luck, - M.S.