private void AttachToExistingJVM(JavaVMInitArgs jvmInitArgs)
{
int virtualMachines;
IntPtr javaVM;
int result = JNINativeImports.JNI_GetCreatedJavaVMs(out javaVM, 1, out virtualMachines);
if (result != JNIConstants.JNI_OK)
{
throw new InvalidOperationException($"Error when creating Java Virtual Machine. [JNI_GetCreatedJavaVMs -> Return code: { result }].");
}
if (virtualMachines > 0)
{
this.JavaEnvironment.VirtualMachine = new JavaVM(javaVM);
JavaEnvironment env;
result = this.JavaEnvironment.VirtualMachine.AttachCurrentThread(out env, jvmInitArgs);
this.JavaEnvironment = env;
if (result != JNIConstants.JNI_OK)
{
throw new InvalidOperationException($"Error when creating Java Virtual Machine. [AttachCurrentThread -> Return code: { result }].");
}
}
}
/// <summary>
/// Loads Java Environment and Virtual Machine.
/// </summary>
/// <param name="path"> On Windows: Path to jvm.dll file. </param>
/// <param name="parameters"> Optional arguments for virtual machine. </param>
/// <param name="jniVersion"> Correct JNI version. See: <see cref="JNIConstants"/>. </param>
/// <param name="attachToExistingJVM"></param>
public void Load(string path, IDictionary <string, string> parameters = null, int jniVersion = JNIConstants.JNI_VERSION_1_8, bool attachToExistingJVM = false)
{
if (string.IsNullOrEmpty(path) ||
!File.Exists(path))
{
throw new ArgumentException("You must specify the correct location of JVM library.", "path");
}
// Set the working directory to directory with JVM library.
Directory.SetCurrentDirectory(Path.GetDirectoryName(path));
var jvmInitArgs = new JavaVMInitArgs
{
version = jniVersion,
ignoreUnrecognized = JavaConverter.ToByte(true)
};
if (parameters != null &&
parameters.Count > 0)
{
jvmInitArgs.nOptions = parameters.Count;
var options = new List <JavaVMOption>();
foreach (var kvp in parameters)
{
options.Add(new JavaVMOption
{
optionString = Marshal.StringToHGlobalAnsi($"{ kvp.Key }={ kvp.Value }")
});
}
JavaVMOption[] parsedOptions = options.ToArray();
fixed(JavaVMOption *a = &parsedOptions[0])
{
jvmInitArgs.options = a;
}
}
if (!attachToExistingJVM)
{
IntPtr environment;
IntPtr javaVM;
int result = JNINativeImports.JNI_CreateJavaVM(out javaVM, out environment, &jvmInitArgs);
if (result != JNIConstants.JNI_OK)
{
throw new InvalidOperationException($"Error when creating Java Virtual Machine. [JNI_CreateJavaVM -> Return code: { result }].");
}
this.JavaEnvironment = new JavaEnvironment(environment);
this.JavaEnvironment.VirtualMachine = new JavaVM(javaVM);
}
else
{
this.AttachToExistingJVM(jvmInitArgs);
}
this.Gateway = new GatewayManager(this);
}
