private void AttachToCurrentJVM(JavaVMInitArgs args)
{
// This is only required if you want to reuse the same instance of the JVM
// This is especially useful if you are using JNI in a webservice. see page 89 of the
// Java Native Interface: Programmer's Guide and Specification by Sheng Liang
if (AttachToCurrentJVMThread)
{
int nVMs;
IntPtr javaVirtualMachine;
int res = JavaVM.JNI_GetCreatedJavaVMs(out javaVirtualMachine, 1, out nVMs);
if (res != JNIReturnValue.JNI_OK)
{
throw new Exception("JNI_GetCreatedJavaVMs failed (" + res.ToString() + ")");
}
if (nVMs > 0)
{
jvm = new JavaVM(javaVirtualMachine);
res = jvm.AttachCurrentThread(out env, args);
if (res != JNIReturnValue.JNI_OK)
{
throw new Exception("AttachCurrentThread failed (" + res.ToString() + ")");
}
}
}
}
/// <summary>
///
/// </summary>
/// <param name="options"></param>
/// <param name="AddToExistingJVM"></param>
/// <param name="targetVersion">Specified the version</param>
public void LoadVM(Dictionary <string, string> options, bool AddToExistingJVM = false, JNIVersion targetVersion = JNIVersion.JNI_VERSION_10)
{
// Set the directory to the location of the JVM.dll.
// This will ensure that the API call JNI_CreateJavaVM will work
// TODO : maybe remove this after changing DLLImport by Assembly dynamic loading
// This probably break pathes to ressources
// Directory.SetCurrentDirectory(Path.GetDirectoryName(JavaNativeInterface.__jvmDllPath));
var args = new JavaVMInitArgs();
args.version = (int)targetVersion;
args.ignoreUnrecognized = JavaVM.BooleanToByte(true); // True
if (options.Count > 0)
{
args.nOptions = options.Count;
var opt = new JavaVMOption[options.Count];
int i = 0;
foreach (KeyValuePair <string, string> kvp in options)
{
string optionString = kvp.Key.ToString() + "=" + kvp.Value.ToString();
opt[i++].optionString = Marshal.StringToHGlobalAnsi(optionString);
}
fixed(JavaVMOption *a = &opt[0])
{
// prevents the garbage collector from relocating the opt variable as this is used in unmanaged code that the gc does not know about
args.options = a;
}
}
if (!AttachToCurrentJVMThread)
{
IntPtr environment;
IntPtr javaVirtualMachine;
int result = JavaVM.JNI_CreateJavaVM(out javaVirtualMachine, out environment, &args);
if (result != JNIReturnValue.JNI_OK)
{
throw new Exception("Cannot create JVM " + result.ToString());
}
jvm = new JavaVM(javaVirtualMachine);
env = new JNIEnv(environment);
}
else
{
AttachToCurrentJVM(args);
}
}
protected virtual void Dispose(bool disposing)
{
// free native resources if there are any.
foreach (KeyValuePair <string, IntPtr> javaClass in usedClasses)
{
if (javaClass.Value != IntPtr.Zero)
{
env.DeleteGlobalRef(javaClass.Value);
usedClasses[javaClass.Key] = IntPtr.Zero;
}
}
for (int i = 0, end = usedObject.Count; i < end; ++i)
{
IntPtr javaObject = usedObject[i];
if (javaObject != IntPtr.Zero)
{
env.DeleteLocalRef(javaObject);
usedObject[i] = IntPtr.Zero;
}
}
if (disposing)
{
// free managed resources
if (jvm != null)
{
jvm.Dispose();
jvm = null;
}
if (env != null)
{
env.Dispose();
env = null;
}
}
}
/// <summary>
///
/// </summary>
/// <param name="forcedJVMDllPath"></param>
public JavaNativeInterface(string forcedJVMDllPath = "")
{
if (forcedJVMDllPath.Length > 0)
{
JavaNativeInterface.__jvmDllPath = forcedJVMDllPath;
}
else if (JavaNativeInterface.__jvmDllPath.Length == 0)
{
// Search for a java runtime near the current assembly
string codeBase = Assembly.GetExecutingAssembly().CodeBase;
UriBuilder uri = new UriBuilder(codeBase);
string assemblyDir = Path.GetDirectoryName(Uri.UnescapeDataString(uri.Path)) + Path.DirectorySeparatorChar;
string[] searchResult = Directory.GetFiles(assemblyDir, "jvm.dll", SearchOption.AllDirectories);
if (searchResult.Length > 0)
{
JavaNativeInterface.__jvmDllPath = searchResult[0];
}
else
{
string envJavaHome = Environment.GetEnvironmentVariable("JAVA_HOME");
if (envJavaHome.Length > 0)
{
searchResult = Directory.GetFiles(envJavaHome, "jvm.dll", SearchOption.AllDirectories);
if (searchResult.Length > 0)
{
JavaNativeInterface.__jvmDllPath = searchResult[0];
}
}
else
{
foreach (string key in JavaNativeInterface.JAVA_REGISTRY_KEYS)
{
string javaVersion = (string)Registry.GetValue(key, "CurrentVersion", null);
if (javaVersion == null)
{
continue;
}
else
{
JavaNativeInterface.__javaVersion = javaVersion;
string javaKey = Path.Combine(key, javaVersion);
string javaHomeKey = (string)Registry.GetValue(javaKey, "JavaHome", null);
if (javaHomeKey == null)
{
continue;
}
else
{
searchResult = Directory.GetFiles(javaHomeKey, "jvm.dll", SearchOption.AllDirectories);
if (searchResult.Length > 0)
{
JavaNativeInterface.__jvmDllPath = searchResult[0];
break;
}
else
{
continue;
}
}
}
}
if (JavaNativeInterface.__jvmDllPath.Length == 0) // no runtime found in registry keys
{
throw new Exception("No Java runtime available to launch a JVM, please install java or contact your IT administrator.");
}
}
}
Console.WriteLine("Using " + JavaNativeInterface.__jvmDllPath);
JavaVM.loadAssembly(JavaNativeInterface.__jvmDllPath);
}
}
private JValue[] ParseParameters(IntPtr javaClass, string sig, params object[] param)
{
JValue[] retval = new JValue[param.Length];
int startIndex = sig.IndexOf('(') + 1;
for (int i = 0; i < param.Length; i++)
{
string paramSig = "";
if (sig.Substring(startIndex, 1) == "[")
{
paramSig = sig.Substring(startIndex++, 1);
}
if (sig.Substring(startIndex, 1) == "L")
{
paramSig = paramSig + sig.Substring(startIndex, sig.IndexOf(';', startIndex) - startIndex);
startIndex++; // skip past ;
}
else
{
paramSig = paramSig + sig.Substring(startIndex, 1);
}
startIndex = startIndex + (paramSig.Length - (paramSig.IndexOf("[", StringComparison.Ordinal) + 1));
if (param[i] is string)
{
if (!paramSig.Equals("Ljava/lang/String"))
{
throw new Exception("Signature (" + paramSig + ") does not match parameter value (" + param[i].GetType().ToString() + ").");
}
retval[i] = new JValue()
{
l = env.NewString(param[i].ToString(), param[i].ToString().Length)
};
}
else if (param[i] == null)
{
retval[i] = new JValue(); // Just leave as default value
}
else if (paramSig.StartsWith("["))
{
retval[i] = ProcessArrayType(javaClass, paramSig, param[i]);
}
else
{
retval[i] = new JValue();
FieldInfo paramField = retval[i].GetType().GetFields(BindingFlags.Public | BindingFlags.Instance).AsQueryable().FirstOrDefault(a => a.Name.ToUpper().Equals(paramSig));
if ((paramField != null) && ((param[i].GetType() == paramField.FieldType) || ((paramField.FieldType == typeof(bool)) && (param[i] is byte))))
{
paramField.SetValueDirect(__makeref(retval[i]), paramField.FieldType == typeof(bool) // this is an undocumented feature to set struct fields via reflection
? JavaVM.BooleanToByte((bool)param[i])
: param[i]);
}
else
{
throw new Exception("Signature (" + paramSig + ") does not match parameter value (" + param[i].GetType().ToString() + ").");
}
}
}
return(retval);
}
