来自Java的DLL调用返回一个不满意的链接错误

Question

编辑：问题已解决

我创建了一个新项目并导入了源文件。(在尝试了太多选项后，项目配置错误。(我似乎混淆了加载和加载库函数。加载需要一个包含文件后缀的绝对路径，例如：

static { System.load("c:/windows/system32/jnpout32.dll");}

尝试调用jnpout32.dll时(http://www.hytherion.com/beattidp/comput/pport.htm)从Eclipse中的Java(Windows 7，Java SE1.7(我收到错误：

Exception in thread "main" java.lang.UnsatisfiedLinkError: EEGTrigger.ioPort.Out32(SS)V
at EEGTrigger.ioPort.Out32(Native Method)
at EEGTrigger.pPort.setAllDataBits(pPort.java:53)
at EEGTrigger.pPort.<init>(pPort.java:19)
at EEGTrigger.EEGTrigger.main(EEGTrigger.java:11)

dll文件位于System32中的src文件夹中，并且位于C:\Users[user]\AppData\Local(如System.getenv((所示(中

在用户条目下的Classpath中，文件也被加载

jnpout32.dll - [Project]src[Project]

并且它在包浏览器中的引用库下可见

这两条线都不起作用：

static { System.loadLibrary("jnpout32"); }
static { System.load("c:/windows/system32/jnpout32"); }

(按照java.lang.UnsisfiedLinkError-JNI中的建议加载(

我已经确认(基于java.lang.UnsisfiedLinkError(

System.getProperty("java.library.path")

返回system32路径。

java项目的完整代码(我只编写了EEGTrigger类。其余的都是dll。(：

package EEGTrigger;    
public class EEGTrigger {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("Starting trigger...");
        pPort lpt1 = new pPort();

        testProtocol(lpt1);

    }
    private static void testProtocol(pPort lpt1) {
        // TODO Auto-generated method stub
        short selectTrigger = 0;
        sendPulse(lpt1, selectTrigger);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        selectTrigger = 1;
        sendPulse(lpt1, selectTrigger);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        selectTrigger = 2;
        sendPulse(lpt1, selectTrigger);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        selectTrigger = 3;
        sendPulse(lpt1, selectTrigger);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        selectTrigger = 4;
        sendPulse(lpt1, selectTrigger);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        selectTrigger = 0;
        sendPulse(lpt1, selectTrigger);
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    /**
     * @param lpt1
     */
    public static void sendPulse(pPort lpt1, short selectTrigger) {
        short trigger = 0;
        short targetTrigger = 255;
        short stimulusOnsetAsynchrony = 64;
        short trialOnsetTrigger = 32;
        short triggerOff = 0;
        switch (selectTrigger) { 
            case 1 :    trigger = targetTrigger;
                        break;
            case 2 :    trigger = stimulusOnsetAsynchrony;
                        break;
            case 3 :    trigger = trialOnsetTrigger;
                        break;
            case 4 :    trigger = triggerOff;
                        break;
            default :   trigger = triggerOff;
                        break;
        }
        lpt1.output(trigger);
        try {
            Thread.sleep(50);   // 50 milliseconds
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        lpt1.output(triggerOff);
    }
}

package EEGTrigger;
/* Definitions in the build of jnpout32.dll are:            */
/*   short _stdcall Inp32(short PortAddress);               */
/*   void _stdcall Out32(short PortAddress, short data);    */

public class ioPort
{
    // declare native methods of 'jnpout32.dll'
    // output a value to a specified port address
    public native void Out32(short PortAddress, short data);
    // input a value from a specified port address
    public native short Inp32(short PortAddress);
    // load 'jnpout32.dll'
    static { System.loadLibrary("jnpout32");}
    //static { System.load("c:/windows/system32/jnpout32"); }
}
package EEGTrigger;
// ** Derived from information provided on the web by Dr. Kenneth G. Schweller,
// ** ( http://web.bvu.edu/faculty/schweller/ ) and his Mars Rover project page.
public class pPort
{
   ioPort pp;                   // wrapper class for 'Jnpout32.dll'
                               // with methods:
                               //    int Out32(int port, int value);
                               //    int Inp32(int port);
   short portAddress;            // address of data port
   short currentVal;             // current value of port bits
   public pPort()
   {
      pp = new ioPort();
      portAddress = (short)0x378;     // Hex Address of Data Byte of PC Parallel Port
      setAllDataBits((short)0);       // initialize port bits to 0
      currentVal = 0x00;
   }
   // wrap ParallelPort output method
   public void output(short port, short value)
   {
      pp.Out32(port, value);
   }
   // wrap ParallelPort input method
   public short input(short port)
   {
      return pp.Inp32(port);
   }
    // output to default Data port
    public void output(short value)
    {
      pp.Out32(portAddress, value);
    }
    // input from default Data port
    public short input()
    {
      return pp.Inp32(portAddress);
    }

  /**
   * set all bits on Data port to zero
   **/
   public void setAllDataBits(short value)
   {
      pp.Out32(portAddress, value);
      currentVal = value;
   }

   // For users who prefer dealing with Pin numbers
   //    Set Pin <pin> to <value>
   public void setPin(short pin, short value)
   {
      if (pin >= 2 && pin <= 9)
         // just set the corresponding Data bit to indicted value
         setDataBit((short)(pin-2), value);
   }

   /**
    * Set Data Bit at selected index to a value of 1 or 0
    * while preserving current values of all other Data bits
    **/
   void setDataBit(short index, short value)
   {
      switch(index)
      {
         case 0:
           if (value==0)                        //  Set Data[0] to 0
              currentVal = (short) (currentVal & 0xFE);
                                                       //      aaaa aaaa  currentVal
                                                //  AND 1111 1110  mask
                                                //      =========
                                                //      aaaa aaa0  new currentVal
           else                                 //  Set Data[0] to 1
              currentVal = (short) (currentVal | 0x01);
                                                        //      aaaa aaaa   currentVal
                                                //  OR  0000 0001   mask
                                                //      =========
                                                //      aaaa aaa1   new currentVal
           break;
         case 1:
           if (value==0)
              currentVal = (short) (currentVal & 0xFD);
                                                        //  currentVal = aaaa aa0a
           else
              currentVal = (short) (currentVal | 0x02);
                                                        //  currentVal = aaaa aa1a
           break;
         case 2:
           if (value==0)
              currentVal = (short) (currentVal & 0xFB);
                                                        //  currentVal = aaaa a0aa
           else
              currentVal = (short) (currentVal | 0x04);
                                                        //  currentVal = aaaa a1aa
           break;
         case 3:
           if (value==1)
              currentVal = (short) (currentVal & 0xF7);
                                                        //  currentVal = aaaa 0aaa
           else
              currentVal = (short) (currentVal | 0x08);   //  currentVal = aaaa 1aaa
           break;
         case 4:
           if (value==0)
              currentVal = (short) (currentVal & 0xEF);
                                                        //  currentVal = aaa0 aaaa
           else
              currentVal = (short) (currentVal | 0x10);   //  currentVal = aaa1 aaaa
           break;
         case 5:
           if (value==0)
              currentVal = (short) (currentVal & 0xDF);
                                                        //  currentVal = aa0a aaaa
           else
              currentVal = (short) (currentVal | 0x20);   //  currentVal = aa1a aaaa
           break;
         case 6:
           if (value==0)
              currentVal = (short) (currentVal & 0xBF);
                                                        //  currentVal = a0aa aaaa
           else
              currentVal = (short) (currentVal | 0x40);   //  currentVal = a1aa aaaa
           break;
             case 7:
           if (value==0)
              currentVal = (short) (currentVal &  0x7F);
                                                        //  currentVal = 0aaa aaaa
           else
              currentVal = (short) (currentVal | 0x80);   //  currentVal = 1aaa aaaa
           break;
         default:
           System.out.println("index must be 0 - 7");
      }
      pp.Out32(portAddress, currentVal);
   }

}

以下问题在这方面要么没有帮助，要么不适用：

java.lang.UnsisfiedLinkError

java.lang.UnsisfiedLinkError

java.lang.UnsisfiedLinkError

java.lang.UnsisfiedLinkError

Linux 中的java.lang.UnsisfiedLinkError

eclipse 中的Java.lang.UnsisfiedLink错误

java.lang.UnsisfiedLinkError:dbopen

JNI java.lang.UnsisfiedLinkError

Answer 1

您没有提供太多关于为什么会收到不满意的链接错误的信息。尝试附加完整堆栈跟踪。

只要JVM通过java-Djava.library.path="%WINDIR%/system32/"启动时设置了java.library.path，System.loadLibrary("jnpout32"(就是正确的

如果要使用System.load，则应该执行类似System.load("c:\windows/system32/"+System.mapLibraryName("jnpout32"((的操作来生成本机库名称和扩展名。

如果你正确地使用了它们，并且两者都继续失败，那么你的错误就在其他地方，比如丢失了一个依赖库。