I want to use a dll (IEC driver) in Java, for that I am using JNA. The problem in pseudo code:

• start the server
• allocate new memory for an array (JNA)
• client connect
• writing values from an array to the memory
• sending this array to the client
• client disconnect
• new client connect
• allocate new memory for an array (JNA) -> JVM crash (EXCEPTION_ACCESS_VIOLATION)

The JVM crash not by primitve data types and if the values will not writing from the array to the memory.

the code in c:

struct DataAttributeData CrvPtsArrayDAData = {0};

CrvPtsArrayDAData.ucType = DATATYPE_ARRAY; 
CrvPtsArrayDAData.pvData = XYValDAData;  


XYValDAData[0].ucType = FLOAT;
XYValDAData[0].uiBitLength = sizeof(Float32)*8;
XYValDAData[0].pvData = &(inUpdateValue.xVal);


XYValDAData[1].ucType = FLOAT;
XYValDAData[1].uiBitLength = sizeof(Float32)*8;
XYValDAData[1].pvData = &(inUpdateValue.yVal);


Send(&CrvPtsArrayDAData, 1);

the code in Java:

DataAttributeData[] data_array = (DataAttributeData[]) new DataAttributeData()
                        .toArray(d.bitLength);

for (DataAttributeData d_temp : data_array) {

    d_temp.data = new Memory(size / 8);
    d_temp.type = type_iec;
    d_temp.bitLength = size;
    d_temp.write();
}

d.data = data_array[0].getPointer();

And then writing values whith this code:

for (int i = 0; i < arraySize; i++) {
    DataAttributeData dataAttr = new DataAttributeData(d.data.share(i * d.size()));
    dataAttr.read();
    dataAttr.data.setFloat(0, f[i]);
    dataAttr.write();
}

the struct in c:

struct DataAttributeData{
unsigned char ucType;           
int iArrayIndex; 
unsigned int uiBitLength;   
void * pvData;};

the struct in java:

public static class DataAttributeData extends Structure {

    public DataAttributeData(Pointer p) {
        // TODO Auto-generated constructor stub

        super(p);
    }

    public DataAttributeData() {
        // TODO Auto-generated constructor stub

        super();
    }

    public byte type;
    public int iArrayIndex;
    public int bitLength;
    public Pointer data;

    @Override
    protected List<String> getFieldOrder() {
        // TODO Auto-generated method stub
        return Arrays.asList(new String[] { "type", "iArrayIndex",
                "bitLength", "data" });
    }
}

Can anybody help me?