com_vladium_utils_systeminformation.c

采用JNI取得Windows系统CPU,内存等数据

         break;

      case VER_PLATFORM_WIN32s:

         strcat(buf,"Win32s ");
         break;
   }
     
next_label:

   strcat(buf,"on ");
   // Get and display the name of the computer. 
   bufCharCount = INFO_BUFFER_SIZE;
   if( !GetComputerName( infoBuf, &bufCharCount ) )
    	goto next_label_2; 
   strcat(buf, infoBuf ); 
    
next_label_2:
    strcat(buf," (");
    if (!(osvi.dwPlatformId==VER_PLATFORM_WIN32_WINDOWS && 
osvi.dwMajorVersion == 4 && osvi.dwMinorVersion == 0)) {
	    // Win95 does not keep CPU info in registry
	    LONG lRet;
	    HKEY hKey;
            char szOrigCPUType[BUFSIZE];
	    int i=0;
            DWORD dwBufLen=BUFSIZE;
            lRet = RegOpenKeyEx( HKEY_LOCAL_MACHINE,
               "HARDWAREDESCRIPTIONSystemCentralProcessor",
               0, KEY_QUERY_VALUE, &hKey );
            if( lRet != ERROR_SUCCESS ) {
		    goto next_label_3;
		}

            lRet = RegQueryValueEx( hKey, "ProcessorNameString", NULL, NULL,
               (LPBYTE) szOrigCPUType, &dwBufLen);
            if( (lRet != ERROR_SUCCESS) || (dwBufLen > BUFSIZE) ) {
		goto next_label_3;
	    }
            RegCloseKey( hKey );
	    if (strlen(szOrigCPUType)>0) {
		while(szOrigCPUType[i]==' ' && szOrigCPUType[i]!=0) i++;
		strcat(buf,szOrigCPUType+i);
	    } else goto next_label_3;
    } else {
next_label_3:
	    if (processorArchitecture==PROCESSOR_ARCHITECTURE_UNKNOWN) strcat(buf,"unknown_arch");
	    else if (processorArchitecture==PROCESSOR_ARCHITECTURE_INTEL) {
		    strcat(buf,"Intel ");
		    sprintf(buf2,"level %d ",processorLevel);
		    strcat(buf,buf2);
	    } else if (processorArchitecture==PROCESSOR_ARCHITECTURE_IA64) strcat(buf,"IA64 ");
	    else if (processorArchitecture==PROCESSOR_ARCHITECTURE_MIPS) strcat(buf,"MIPS ");
	    else if (processorArchitecture==PROCESSOR_ARCHITECTURE_ALPHA) strcat(buf,"Alpha ");
	    else if (processorArchitecture==PROCESSOR_ARCHITECTURE_PPC) strcat(buf,"PowerPC ");
	    else if (processorArchitecture==PROCESSOR_ARCHITECTURE_SHX) strcat(buf,"SHX ");
	    else if (processorArchitecture==PROCESSOR_ARCHITECTURE_ALPHA64) strcat(buf,"Alpha64 ");
	    else strcat(buf,"unknown_arch ");
    }

    strcat(buf,")");

    return (*env)->NewStringUTF(env,buf);
}


/* ......................................................................... */


/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getProcessID
 * Signature: ()I
 */
JNIEXPORT jint JNICALL
Java_com_vladium_utils_SystemInformation_getProcessID (JNIEnv * env, jclass cls)
{
    return s_PID;
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    setPid
 * Signature: ()I
 */
JNIEXPORT jint JNICALL
Java_com_vladium_utils_SystemInformation_setPid (JNIEnv * env, jclass cls, jint pid)
{
    DWORD errCode;
    LPVOID lpMsgBuf;
    s_PID = pid;
    s_currentProcess = OpenProcess(PROCESS_ALL_ACCESS,FALSE,pid);
    if (s_currentProcess==NULL) {
	    errCode = GetLastError();
	    FormatMessage(
              FORMAT_MESSAGE_ALLOCATE_BUFFER | 
              FORMAT_MESSAGE_FROM_SYSTEM,
              NULL,
              errCode,
              MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
              (LPTSTR) &lpMsgBuf,
              0, NULL );
	    
	    printf("[CPUmon] Could not attach to native process. Error code: %ld Error description: %s",errCode,lpMsgBuf);
	    fflush(stdout);
	    LocalFree(lpMsgBuf);
	    return errCode;
    }
    printf("[CPUmon] Attached to native process.");
    fflush(stdout);
    return 0;
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    detachProcess
 * Signature: ()I
 */
JNIEXPORT jint JNICALL
Java_com_vladium_utils_SystemInformation_detachProcess (JNIEnv * env, jclass cls)
{
    if (!alreadyDetached && s_currentProcess!=NULL) {
	    CloseHandle(s_currentProcess);
	    alreadyDetached = 1;
	    printf("[CPUmon] Detached from native process.");
	    fflush(stdout);
    }
    return 0;
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getProcessCPUTime
 * Signature: ()J
 */
JNIEXPORT jlong JNICALL
Java_com_vladium_utils_SystemInformation_getProcessCPUTime (JNIEnv * env, jclass cls)
{
    FILETIME creationTime, exitTime, kernelTime, userTime;
    DWORD errCode;
    LPVOID lpMsgBuf;
    
    BOOL resultSuccessful = GetProcessTimes (s_currentProcess, & 
creationTime, & exitTime, & kernelTime, & userTime);
    if (!resultSuccessful) {
	    errCode = GetLastError();
	    FormatMessage(
              FORMAT_MESSAGE_ALLOCATE_BUFFER | 
              FORMAT_MESSAGE_FROM_SYSTEM,
              NULL,
              errCode,
              MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
              (LPTSTR) &lpMsgBuf,
              0, NULL );
	    
	    printf("[CPUmon] An error occured while trying to get CPU time.Error code: %ld Error description: %s",errCode,lpMsgBuf);

	    fflush(stdout);
	    LocalFree(lpMsgBuf);
	    return -1;
    }

    return (jlong) ((fileTimeToInt64 (& kernelTime) + fileTimeToInt64 (& userTime)) /
        (s_numberOfProcessors * 10000));
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getMaxMem
 * Signature: ()J
 */
JNIEXPORT jlong JNICALL
Java_com_vladium_utils_SystemInformation_getMaxMem (JNIEnv * env, jclass cls)
{
	MEMORYSTATUS stat;
	GlobalMemoryStatus (&stat);
        return (jlong)(stat.dwTotalPhys/1024);
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getFreeMem
 * Signature: ()J
 */
JNIEXPORT jlong JNICALL
Java_com_vladium_utils_SystemInformation_getFreeMem (JNIEnv * env, jclass cls)
{
        MEMORYSTATUS stat;
	GlobalMemoryStatus (&stat);
        return (jlong)(stat.dwAvailPhys/1024);
}
/* ......................................................................... */


/* define min elapsed time (in units of 10E-7 sec): */
#define MIN_ELAPSED_TIME (10000)

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getProcessCPUUsage
 * Signature: ()D
 */
JNIEXPORT jdouble JNICALL
Java_com_vladium_utils_SystemInformation_getProcessCPUUsage (JNIEnv * env, jclass cls)
{
    FILETIME creationTime, exitTime, kernelTime, userTime, nowTime;   
    LONGLONG elapsedTime;
    DWORD errCode;
    LPVOID lpMsgBuf;
    
    BOOL resultSuccessful = GetProcessTimes (s_currentProcess, & 
creationTime, & exitTime, & kernelTime, & userTime);
    if (!resultSuccessful) {
	    errCode = GetLastError();
	    FormatMessage(
              FORMAT_MESSAGE_ALLOCATE_BUFFER | 
              FORMAT_MESSAGE_FROM_SYSTEM,
              NULL,
              errCode,
              MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
              (LPTSTR) &lpMsgBuf,
              0, NULL );
	    
	    printf("[CPUmon] An error occured while trying to get CPU time. Error code: %ld Error description: %s",errCode,lpMsgBuf);
	    fflush(stdout);
	    LocalFree(lpMsgBuf);
	    return -1.0;
    }
    GetSystemTimeAsFileTime (& nowTime);

    /*
        NOTE: win32 system time is not very precise [~10ms resolution], use
        sufficiently long sampling intervals if you make use of this method.
    */
    
    elapsedTime = fileTimeToInt64 (& nowTime) - fileTimeToInt64 (& creationTime);
    
    if (elapsedTime < MIN_ELAPSED_TIME)
        return 0.0;
    else  
        return ((jdouble) (fileTimeToInt64 (& kernelTime) + fileTimeToInt64 (& userTime))) /
            (s_numberOfProcessors * elapsedTime);
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getProcessCPUPercentage
 * Signature: ()D
 */
JNIEXPORT jdouble JNICALL
Java_com_vladium_utils_SystemInformation_getProcessCPUPercentage (JNIEnv * env, jclass cls)
{
	// Not implemented on Windows
        return (jdouble)(-1.0);
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getMemoryUsage
 * Signature: ()J
 */
JNIEXPORT jlong JNICALL
Java_com_vladium_utils_SystemInformation_getMemoryUsage (JNIEnv * env, jclass cls)
{
    PROCESS_MEMORY_COUNTERS pmc;
    
    if ( GetProcessMemoryInfo( s_currentProcess, &pmc, sizeof(pmc)) )
    {
		return (jlong)(pmc.PagefileUsage/1024);
    } else {
		return (jlong)(0);
    }
}
/* ......................................................................... */

/*
 * Class:     com_vladium_utils_SystemInformation
 * Method:    getMemoryResident
 * Signature: ()J
 */
JNIEXPORT jlong JNICALL
Java_com_vladium_utils_SystemInformation_getMemoryResident (JNIEnv * env, jclass cls)
{
    PROCESS_MEMORY_COUNTERS pmc;
    
    if ( GetProcessMemoryInfo( s_currentProcess, &pmc, sizeof(pmc)) ){
		return (jlong)(pmc.WorkingSetSize/1024);
	} else {
		return (jlong)(0);
	}
}
#undef MIN_ELAPSED_TIME

/* ------------------------------------------------------------------------- */
/* end of file */