Cannot compile on Win10/Netbeans

[Peter Nellemann]

So, having spent a week trying to get things to work, I'm nearly there. As an aside, I haven't worked with Java in nearly 4 years, and never something like JavaCPP before, I'm traditionally a C# developer, but my PhD position tasks me with Java.

Anyways! My goal is pretty much as we suspect> I want to communicate with a C++ .DLL from my Java code. So far, I've done the following, using the Netbeans IDE on a  64-bit installation of Windows10 with Maven for building and CygWin for terminal functionality:

Added the JavaCPP portions to the pom.xml as follows:

<build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.3</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>properties</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
                     
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>nbm-maven-plugin</artifactId>
                <extensions>true</extensions>
            </plugin>
           
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>1.2.1</version>
                <executions>
                    <execution>
                        <id>javacpp</id>
                        <phase>process-classes</phase>
                        <goals>
                            <goal>exec</goal>
                        </goals>
                        <configuration>
                            <executable>java</executable>
                            <arguments>
                                <argument>-jar</argument>      
                                <argument>C:\Users\pne\.m2\repository\org\bytedeco\javacpp\1.1\javacpp-1.1.jar</argument>
                                <!--<argument>${org.bytedeco:javacpp:jar:1.1}</argument>-->
                                <argument>-classpath</argument>
                                <argument>${project.build.outputDirectory}</argument>
                                <argument>-d</argument>        
                                <argument>${project.build.outputDirectory}</argument>
                            </arguments>
                        </configuration>
                    </execution>
                </executions>
            </plugin>            
        </plugins>
    </build>

    <dependencies>
        <dependency>
            <groupId>org.netbeans.api</groupId>
            <artifactId>org-netbeans-api-annotations-common</artifactId>
            <version>RELEASE80</version>
        </dependency>
       
        <dependency>
            <groupId>net.java.dev.jna</groupId>
            <artifactId>jna</artifactId>
            <version>4.2.1</version>
        </dependency>
       
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>javacpp</artifactId>
            <version>1.1</version>
        </dependency>
    </dependencies>

the argument for -jar does not work with the commented-out code, but linking directly to the repository does.

My code I'm trying to compile:

package dk.sdu.mmmi.dk.sdu.mmmi.controleum.impl.modelcommunicator;

/**
 *
 * @author pne
 */
import org.bytedeco.javacpp.*;
import org.bytedeco.javacpp.annotation.*;

@Platform(include="MAEXP.h")
@Namespace("NativeLibrary")
public class MAEXP {
    public static class MAEXPClass extends Pointer{
        static {Loader.load();}
        public MAEXPClass() { allocate(); }
        public native void  allocate();
       
        public native @StdString String stringTest(String txt);
    }    
}

Trying to compile gives an error with cl command. So I tried some C++ compilers. Currently, I have a grand total of three installed, neither of which will work. Gah! Installed compilers are the Netbeans C++ compiler, Visual Studio 2015 C++ and mingwe-w64 compiler. All to no avail, it still refuses to work. My error:

Enter code here.--- nbm-maven-plugin:3.14:manifest (default-manifest) @ dk.sdu.mmmi.controleum.impl.modelcommunicator ---
NBM Plugin generates manifest
Adding on module's Class-Path:
    net.java.dev.jna:jna:jar:4.2.1
    org.bytedeco:javacpp:jar:1.1

--- exec-maven-plugin:1.2.1:exec (javacpp) @ dk.sdu.mmmi.controleum.impl.modelcommunicator ---
Generating C:\Workspace\Controleum\dk.sdu.mmmi.controleum.impl.modelcommunicator\target\classes\jniMAEXP.cpp
Compiling C:\Workspace\Controleum\dk.sdu.mmmi.controleum.impl.modelcommunicator\target\classes\jniMAEXP.dll
cl "/IC:\Program Files\Java\jdk1.8.0_66\include" "/IC:\Program Files\Java\jdk1.8.0_66\include\win32" C:\Workspace\Controleum\dk.sdu.mmmi.controleum.impl.modelcommunicator\target\classes\jniMAEXP.cpp /W3 /Oi /O2 /EHsc /Gy /GL /MD /LD /link /OUT:C:\Workspace\Controleum\dk.sdu.mmmi.controleum.impl.modelcommunicator\target\classes\jniMAEXP.dll
Exception in thread "main" java.io.IOException: Cannot run program "cl": CreateProcess error=2, The system cannot find the file specified
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
    at org.bytedeco.javacpp.tools.Builder.compile(Builder.java:318)
    at org.bytedeco.javacpp.tools.Builder.generateAndCompile(Builder.java:372)
    at org.bytedeco.javacpp.tools.Builder.build(Builder.java:643)
    at org.bytedeco.javacpp.tools.Builder.main(Builder.java:773)
Caused by: java.io.IOException: CreateProcess error=2, The system cannot find the file specified
    at java.lang.ProcessImpl.create(Native Method)
    at java.lang.ProcessImpl.<init>(ProcessImpl.java:386)
    at java.lang.ProcessImpl.start(ProcessImpl.java:137)
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
    ... 4 more
------------------------------------------------------------------------
BUILD FAILURE
------------------------------------------------------------------------
Total time: 6.609s
Finished at: Wed Dec 02 15:14:06 CET 2015
Final Memory: 19M/219M..

If anyone has any idea of how to proceed from here, I would be very grateful, as I'm at my wits end and Java is not exactly my Fort=e *yet, I hope, considering this as yet another learning opportunity). And if Java is bad, C++ is worse, as I've never touched it prior to now.

[Samuel Audet]

On 12/02/2015 11:26 PM, Peter Nellemann wrote:
> Exception in thread "main" java.io.IOException: Cannot run program "cl": CreateProcess error=2, The system cannot find the file specified

The "cl.exe" compiler comes with Visual Studio, and you said you've
installed it, but are you making sure to run this inside a "Native Tools
Command Prompt"?

Samuel