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我试图解决以下问题好几天。我的 JNA 程序在执行特定的本机函数时挂起，调试显示程序控制在 JNA 源中的特定位置丢失。这是详细信息。我在 DLL 中有三个本机函数，我试图用 JNA 访问它们。它们如下

DllExport long calculatePayment(...,Protection   protectionArr[PROTECTION_SIZE],
    Others   othersArr[OTHERS_SIZE],RC  rcArr[RC_SIZE], ...);  
DllExport long bufferCalculatePayment(const char *inputBuffer, char **OutputBuffer); 
DllExport long fileCalculatePayment(const char *InputFile, const char *OutputFile);

对应的Java接口映射如下

public interface DLLInterface extends Library {

public DLLInterface INSTANCE = (DLLInterface) Native.loadLibrary("DLLInterface",   
DLLInterface.class);
/* Others Structure is as follows.. protection and rc structure is similar with their   
own initialize methods*/

public static final NativeLong othersSize = new NativeLong(20);

class Others extends Structure {
    public static class ByValue extends Others implements Structure.ByValue {
    }
    public double amt = 0.00;    
    public NativeLong flag = new NativeLong();     
    public byte[] details = new byte[50]; //
    public byte[] mDetails = new byte[50]; 
    public NativeLong flag2 = new NativeLong();    

    public static Structure[] initialize() {
        Others result = new Others();
        Others[] resultArr = (Others[]) result.toArray(othersSize);
        return resultArr;
     }

    public void setDetails(String dataIn) {
        Arrays.fill(details, (byte) 0);
        if (dataIn != null) {
            String data = dataIn;
            if (data.length() > 49) {
                data = data.substring(0, 49);
            }
            byte[] bytes = data.getBytes();
            System.arraycopy(bytes, 0, details, 0, bytes.length);
        }
    }

 //other set functions here    
@Override
protected List getFieldOrder() {      
return Arrays.asList("amt", "flag", "details", "mDetails", "flag2");        
 }

}
//Protection and RC sturcutre are similar. Both structures contain fields    
             of the type byte[] and double.
//Prototypes for native functions       

 NativeLong calculatePayment(.....Structure[] protectionArr, Structure[]   
 othersStruct , Structure[] rcArr,.....) ;

 Nativelong bufferCalculatePayment(Strubg inputBuffer, PointerByReference 
 OutputBuffer); 

 Natuvelong fileCalculatePayment(String InputFile, String OutputFile);

}

//In main function I am calling these functions as follows - 
public static void main(String args[]){
 DLLInterface.Others[] othersArr = (DLLInterface.Others[])    
 DLLInterface.Others.initialize(); 
 DLLInterface.RC[] rcArr = (DLLInterface.RC[]) DLLInterface.RC.initialize(); 
 DLLInterface.Protection[] protectionArr = (DLLInterface.Protection[])   
 DLLInterface.Protection.initialize();  //static method
         ...
         //passing values to structures
         ...
     //few native functions calls goes here (they get executed   successfully

 NativeLong y =  
 DLLInterface.INSTANCE.calculatePayment(....protectionArr,othersArr,rcArr, ...);

 String inputBuffer = ""<?xml version= \"1.0\" ?><ROOT><REQ><TRANSACT> 
 <ID>12345</ID><METHOD>COMPOUND</METHOD><AMT>50000</AMT><TERM>360</TERM></TRANSACT>  
 </REQ></ROOT>";

 NativeLong b = DLLInterface.INSTANCE.bufferCalculatePayment(inputBuffer,pRef);

 DLLInterface.INSTANCE.fileCalculatePayment("InFile","OutFile");

 }

对于所有三个函数，程序都被挂起......永远不会被终止，所以我尝试调试代码。然后我发现在调用 Object result = invoke(args, nativeType, allowObjects) 之后，程序控制在跟随for循环后丢失了。我列出了来自 Function.java 文件源 - JNA 源的几行源代码

public Object invoke(Class returnType, Object[] inArgs, Map options){
.......
result = resultConverter.fromNative(result, context);
    ....
// Sync all memory which might have been modified by the native call
    if (Structure.ByReference[].class.isAssignableFrom(inArg.getClass()))
    {   Class type = inArg.getClass().getComponentType();  
                Structure[] ss = (Structure[])inArg;
        for (int si=0;si < ss.length;si++) {
         Pointer p =array.getPointer(Pointer.SIZE * si);
         ss[si] =Structure.updateStructureByReference(type, ss[si], p); 
    }  //////*///////////////////////*/program control gets lost after this
}.........}

任何猜测可能是什么问题？本机函数是否有问题或我的参数映射不正确。任何帮助深表感谢..

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