JNI and accessing a subclass

I have a Java program that communicates to a C program. I have written JNI before but my output structure was more simplistic and the C structure just contained doubles/ints and arrays of doubles/ints.

Now my structure contains a substructure (class/subclass) and I don't know how to change the code to access the subclass data/fields.

My C code looked like this but how do I access a value like DefaultFeeAmount if you look at my Java Class below this code....how do I get to the elements within the subclass?

C straightforward....

{
    jclass out_rec_cls = jenv->GetObjectClass(ptrTo_out_rec);
    jfieldID fldID, fldID2;
    jintArray arr;
    jdoubleArray da开发者_运维百科rr;
    jobjectArray oarr;
    jsize len;//,len2;
    jint *arrElems;
    jdouble *darrElems;
    jobject *oarrElems;
    int i;
    char temp_str[100],temp_str2[10000];

    fldID = jenv->GetFieldID(out_rec_cls, "ErrorCode", "I");
    if(fldID != NULL)
        jenv->SetIntField(ptrTo_out_rec, fldID, out_rec->error_code);
}

Java

class FeeOutput {
    public double DefaultFeeAmount;
    public double MaximumAmount;
    public int FeeID;
    public int CompType;
    public int Handling;
    public int CapType;
    public int ProfitType;
    public int EffectiveDateMonth;
    public int EffectiveDateDay;
    public int EffectiveDateYear;
    public int VendorBasedFee;
    public int DealerRequestedFee;
    public int DealerFixedTranFee;
    public double FeeAmount;
    public int FeeCompliant;
    public String FeeName = "";

    public FeeOutput() {
    }
}

public class VFeeOutput {
    public static final int NUM_FEES = 100;
    public FeeOutput[] FeeStruct = new FeeOutput[NUM_FEES];

    public int ErrorCode;

    public String ErrorString = "";

    public String Version = "";

    public VFeeOutput() {
    }
}

As a wide-spread Java convention tip, please start variable names with lower case. Here how you can access "struct" fields in Java.

public class VFeeOutput {
    public static final int NUM_FEES = 100;
    public FeeOutput[] FeeStruct = new FeeOutput[NUM_FEES];
    public int ErrorCode;
    public String ErrorString = "";
    public String Version = "";
    public VFeeOutput() {
    }

    private void loopThoughtFeeOutput() {
        for(FeeOutput feeOutput : FeeStruct) {
            feeOutput.CompType = ...;
        }
        // or
        for(int i = 0; i < FeeStruct.length; i++) {
            FeeStruct[0].CompType = ...;
        }
    }
}