Answer 1

Making the wrapper class explicitly inherit from the desired type did the trick in this case:

%typemap(javabase) UserStream "com.jphysx.SWIGTYPE_p_NxStream";

There were some methods in the wrapper class with which I had similar problems, but I simply removed them from the SWIG interface file because they aren't going to be called from the Java code anyway.

Edit: this does not work. Since the wrapper type inherits from another wrapper type, it suddenly has two swigCPtr fields. The one in the subtype is initialized, the one in the supertype remains 0... but this is the one that gets used when you use the supertype somewhere.

Edit 2: I finally solved the problem, by adding a method to the Java wrapper class to convert the UserStream object to a SWIGTYPE_p_NxStream object:

%typemap(javacode) UserStream %{
    public native com.JPhysX.SWIGTYPE_p_NxStream toNxStreamPtr();
%}

This JNI method was hand-written outside SWIG's stuff:

JNIEXPORT jobject JNICALL Java_physics_UserStream_toNxStreamPtr(JNIEnv *env, jobject userStreamObject) {
    jclass userStreamClass = env->GetObjectClass(userStreamObject);
    jmethodID getCPtrMethodID = env->GetStaticMethodID(userStreamClass, "getCPtr", "(Lphysics/UserStream;)J");

    jlong cPtr = env->CallStaticLongMethod(userStreamClass, getCPtrMethodID, userStreamObject);
    jboolean futureUse = false;

    jclass nxStreamPtrClass = env->FindClass("com/JPhysX/SWIGTYPE_p_NxStream");
    jmethodID nxStreamPtrConstructor = env->GetMethodID(nxStreamPtrClass, "<init>", "(JZ)V");
    jobject nxStreamPtrObject = env->NewObject(nxStreamPtrClass, nxStreamPtrConstructor, cPtr, futureUse);
    return nxStreamPtrObject;
}

Answered by: Adelaide935 | Posted: 24-02-2022

Similar questions

java - Referencing an external library in an Ant build

We have an ant build script for a project we're developing for a PDA. In eclipse we have a load of referenced libraries and I know how to get them to work when we run the jar on the PDA because we have a .lnk file where you can add the external libraries simply by adding the following: 512#"\J9\PPRO11\bin\j9.exe" -jcl:ppro11 -cp "\dist\WiFiTest.jar;\placelab\lib\placelab.jar" j2medemo.wifi.WiFiTest ...

---

xml - Problem referencing nodes directly when using XPath in Java

I've recently hit a wall with an issue with Java's native XML API (the W3C one) which at its core is that if I try to use a direct XPath expression in my document like, say, //body the XPath is evaluated as false (incorrect behaviour), however if I replace that with //*[1] it evaluates as true (desired behaviour). I have checked numerous times and with different document...

---

In Java is there a performance difference between referencing a field through getter versus through a variable?

Is there any differences between doing Field field = something.getSomethingElse().getField(); if (field == 0) { //do something } somelist.add(field); versus if (something.getSomethingElse().getField() == 0) { //do something } somelist.add(something.getSomethingElse().getField()); Do references to the field through getters incur a performanc...

---

java - Referencing Environment Variables in web.xml

I'm pre-packaging a JSP web-app that relies on some file path settings found within web.xml. These settings are unknown at packaging time, because they reference a path the customer will set when deploying the entire application (of which the web-app is a management interface). It seems that the easiest way to avoid tokens and file modifications in my installer script, is to ask the user for an install location, s...

---

java - Referencing a cloned widgets in gwt

Right now i have my program to clone widgets. problem i am facing is i have to get the data from these widgets(particularly from textbox) on my DB end. But once i clone them i am not sure how do i keep trace on them and know which data goes where as these widgets don't have names(i mean the cloned ones)? Any help is appreciated. Thank you.

---

java - referencing ant script location from within ant file

I have a utility build script that gets called from a variety of project-specific build scripts on a build server. Everything works fine, until the relative directory structure changes. That is: trunk/ utilities/ imported.xml some_resource_file projectName/ importing.xml works just fine, but sometimes we need: trunk/ importing.xml u...

---

sorting - referencing java objects on a sorted map by index?

I have a sorted map and want to reference its ordered objects by their index position. Is this possible? How would I convert a sorted map to an array list while maintaining the ordering, so I can retrieve an object by its index (order). Is this the only way to do it? Ideally I could have this structure, and would know the index of an object within that strucre and could rertieve it by saying: Ob...

---

Best practice for referencing Java inside my JSPs

I'm asking for some opinions on referencing Java code (in my case an enum value) in a JSP. I currently have conditional logic in my JSP like: <c:if test="${actionBean.order.status eq 'complete'}"> show some stuff </c:if> Now, 'complete' is a value associated with an enum in my codebase. Would it be better to reference the enum inside my JSP? If so, how? ...

---

java - referencing a directory from a different project in the properties file of another project

I am a Java novice I am using Eclipse and I have a project (say Main Project) which has in its build path another project (let's call it Second Project). I need to write in the directories section of the properties file of the Main Project the address of certain files which are part of the Second Project (and as result stored in the Second directory). Considering the string properties.dir = ...

---

java - Self referencing symmetrical Hibernate Map Table using @ManyToMany

I have the following class public class ElementBean { private String link; private Set<ElementBean> connections; } I need to create a map table where elements are mapped to each other in a many-to-many symmetrical relationship. @ManyToMany(targetEntity=ElementBean.class) @JoinTable( name="element_elements", joinColumns=@JoinColumn(name="FROM_ELEMENT_ID", nu...

---

Still can't find your answer? Check out these amazing Java communities for help...

Java Reddit Community | Java Help Reddit Community | Dev.to Java Community | Java Discord | Java Programmers (Facebook) | Java developers (Facebook)