Question

我正在创建一个使用JNI的java应用程序。其中一个JNI函数接受枚举作为参数。但是在JNI使用java参数后显示java.lang.NoSuchFieldError。

这是java代码：

private int convert(JacsbclibLoader.BCTemplateEnvelopeType inputTemplateEnvelopeType,      JacsbclibLoader.BCTemplateDataType inputTemplateDataType, JacsbclibLoader.BCTemplateEnvelopeType outputTemplateEnvelopeType, JacsbclibLoader.BCTemplateDataType outputTemplateDataType, byte[] inputData, byte[] outputData, JacsbclibLoader.BCTemplateInfoType_1 suplementaryInfo)
{

    if(outputData != null)
        outputLength = outputData.length;

    status = _bclib.jBCConvertTemplate(inputTemplateEnvelopeType, inputTemplateDataType,inputData, inputData.length, outputTemplateEnvelopeType,                                    outputTemplateDataType, outputData, outputLength, suplementaryInfo);
    return status;
}

这是java中的Native代码：

public enum BCTemplateDataType
{
    BCT_NOT_SPECIFIED(-1),
    BCT_NONE(0),
    BCT_UPEK_LEGACY(1),
    BCT_UPEK_ALPHA(2),
    BCT_UPEK_BETA(3),
    BCT_UPEK_AUTO(4),
    BCT_ANSI(5),
    BCT_ISO_FMR(6),
    BCT_ISO_FMC_NORMAL(7),
    BCT_ISO_FMC_COMPACT(8),
    BCT_ABAPI(9),
    BCT_LAST(10);

    private int value;

    private BCTemplateDataType(int value)
    {
        this.value = value;
    }   
}

public int jBCConvertTemplate(BCTemplateEnvelopeType inputEnvelopeType,
                                  BCTemplateDataType inputDataType,
                                  byte[] inputData,
                                  int inputDataLength,
                                  BCTemplateEnvelopeType outputEnvelopeType,
                                  BCTemplateDataType outputDataType,
                                  byte[] outputData,
                                  int outputDataLength,
                                  BCTemplateInfoType_1 suplementaryInfo)
    {
        ret = BCConvertTemplate(inputEnvelopeType, inputDataType, inputData, inputDataLength, outputEnvelopeType, outputDataType, outputData, outputDataLength, suplementaryInfo);
        return ret;
    };

    private native int BCConvertTemplate(BCTemplateEnvelopeType inputEnvelope,
                                         BCTemplateDataType inputDataType,
                                         byte[] input,
                                         int inputLength,
                                         BCTemplateEnvelopeType outputEnvelope,
                                         BCTemplateDataType outputDataType,
                                         byte[] output,
                                         int outputLength,
                                         BCTemplateInfoType_1 suplementaryInfo);

这是C ++中的JNI代码：

    JNIEXPORT jint JNICALL Java_JacsbclibLoader_BCConvertTemplate
  (JNIEnv *env, jobject obj, jobject inputEnvelope, jobject inputDataType, jbyteArray inputData, jint inputLength, jobject outputEnvelope, jobject outputDataType, jbyteArray outputData, jint outputLength, jobject suplementaryInfo)
{
    LoadLib();


    BCTemplateInfoType_1 supInfo;


    BCTemplateEnvelopeType eInputTemplateEnvelopeType = BCTE_NONE;
    BCTemplateEnvelopeType eOutputTemplateEnvelopeType = BCTE_NONE;

    BCTemplateDataType eInputTemplateDataType = BCT_NONE;
    BCTemplateDataType eOutputTemplateDataType = BCT_NONE;


    jbyte *inputTemplate = env->GetByteArrayElements(inputData, 0);
    jbyte *outputTemplate = NULL;

    if(outputData != NULL)
    {
        MessageBox(NULL,"outputData != NULL","",0);
        jbyte *outputTemplate = env->GetByteArrayElements(outputData, 0);
    }



    jclass cls = env->GetObjectClass(obj);
    jfieldID fIdInputLength = env->GetStaticFieldID(cls, "inputLength", "I");
    jfieldID fIdOutputLength = env->GetStaticFieldID(cls, "outputLength", "I");


    if(pConvertTemplate)
    {


        /*int inputEnvelopeType;
        int inputEnvelopeDataType;
        int outputEnvelopeType;
        int outputEnvelopeDataType;*/

        /*jclass envelopeTypeClass = env->FindClass("JacsbclibLoader");
        MessageBox(NULL,"3.1","",0);
        jmethodID inputEnvelopeGetValueMethod = env->GetMethodID(envelopeTypeClass, "getValue", "I()");
        MessageBox(NULL,"3.2","",0);
        jint inputEnvelopeValue = env->CallIntMethod(inputEnvelope, inputEnvelopeGetValueMethod);

        MessageBox(NULL,"3.3","",0);
        eInputTemplateEnvelopeType = (BCTemplateEnvelopeType)inputEnvelopeValue;
        MessageBox(NULL,"3.4","",0);*/

        jclass inputEnvelopeClass = env->GetObjectClass(inputEnvelope);
        jclass inputEnvelopeDataTypeClass = env->GetObjectClass(inputDataType);
        jclass outputEnvelopeClass = env->GetObjectClass(outputEnvelope);
        jclass outputEnvelopeDataTypeClass = env->GetObjectClass(outputDataType);

        if(suplementaryInfo != NULL)
        {
            MessageBox(NULL,"4","",0);

            int ver;
            int captureCbeffpId;
            int captureEquiptCompliance;
            int captureEquiptId;
            int imgWidth;
            int imgHeight;
            int imgHorizontalResolution;
            int imgVerticalResolution;
            int fingerPos;

            jclass suplementaryClass = env->GetObjectClass(suplementaryInfo);

            jfieldID fIdVersion = env->GetFieldID(suplementaryClass, "version", "I");
            jfieldID fIdCaptureCbeffpid = env->GetFieldID(suplementaryClass, "captureCBEFFPid", "I");
            jfieldID fIdCaptureEquipmentCompliance = env->GetFieldID(suplementaryClass, "captureEquipmentCompliance", "I");
            jfieldID fIdCaptureEquipmentId = env->GetFieldID(suplementaryClass, "captureEquipmentId", "I");
            jfieldID fIdImageWidth = env->GetFieldID(suplementaryClass, "imageWidth", "I");
            jfieldID fIdImageHeigth = env->GetFieldID(suplementaryClass, "imageHeight", "I");
            jfieldID fIdImageHorizontalResolution = env->GetFieldID(suplementaryClass, "imageHorizontalResolution", "I");
            jfieldID fIdImageVerticalResolution = env->GetFieldID(suplementaryClass, "imageVerticalResolution", "I");
            jfieldID fIdFingerPosition = env->GetFieldID(suplementaryClass, "fingerPosition", "I");

            ver = env->GetIntField(suplementaryInfo, fIdVersion);
            captureCbeffpId = env->GetIntField(suplementaryInfo, fIdCaptureCbeffpid);
            captureEquiptCompliance = env->GetIntField(suplementaryInfo, fIdCaptureEquipmentCompliance);
            captureEquiptId = env->GetIntField(suplementaryInfo, fIdCaptureEquipmentId);
            imgWidth = env->GetIntField(suplementaryInfo, fIdImageWidth);
            imgHeight = env->GetIntField(suplementaryInfo, fIdImageHeigth);
            imgHorizontalResolution = env->GetIntField(suplementaryInfo, fIdImageHorizontalResolution);
            imgVerticalResolution = env->GetIntField(suplementaryInfo, fIdImageVerticalResolution);
            fingerPos = env->GetIntField(suplementaryInfo, fIdFingerPosition);

            memset(&suplementaryInfo, 0x00, sizeof(suplementaryInfo));

            supInfo.version = ver;
            supInfo.captureCBEFFPid = captureCbeffpId;
            supInfo.captureEquipmentCompliance = captureEquiptCompliance;
            supInfo.captureEquipmentId = captureEquiptId;
            supInfo.fingerPosition = fingerPos;
            supInfo.imageHeight = imgHeight;
            supInfo.imageHorizontalResolution = imgHorizontalResolution;
            supInfo.imageVerticalResolution = imgVerticalResolution;
            supInfo.imageWidth = imgWidth;

        }

        returnStatus = pConvertTemplate(eInputTemplateEnvelopeType, 
                                       eInputTemplateDataType, (const void *)inputTemplate, (uint32)inputLength, 
                                       eOutputTemplateEnvelopeType, 
                                       eOutputTemplateDataType, 
                                       outputData != NULL ? (void *)outputTemplate : NULL,                                     
                                       (uint32 *)&outputLength,
                                       suplementaryInfo != NULL ? (const void *)&supInfo : NULL);

        env->SetStaticIntField(cls, fIdOutputLength, outputLength);   // It also crashes in windows7

        return returnStatus;

    }
    else
        return returnStatus;
}

这里是JNI引用的第三方库的枚举：typedef enum _tag_BCTemplateDataType { BCT_NOT_SPECIFIED = -1, BCT_NONE = 0, BCT_UPEK_LEGACY, BCT_UPEK_ALPHA, BCT_UPEK_BETA, BCT_UPEK_AUTO, BCT_ANSI, BCT_ISO_FMR, BCT_ISO_FMC_NORMAL, BCT_ISO_FMC_COMPACT, BCT_ABAPI, BCT_LAST } BCTemplateDataType;

Answer 1

正如在这些问题中所指出的，NoSuchFieldError通常在使用错误的字段名称调用GetFieldId时发生，即C代码中使用的名称与Java中定义的字段不匹配（包括前面的L，完整包和类名称），字段名称和尾随分号）：

JNI: NoSuchFieldError

Get object from an object with JNI in C

正确的通话应该类似于：

jfieldID data = (*env)->GetFieldID(env, some_class, "data", "Lorg/someapp/SomeClass$_data;");

我会仔细检查pConvertTemplate中的代码以查找此类错误 - 或者将其发布给我们进行检查。

java中的java.lang.NoSuchFieldError错误

1 个答案: