/**
* From the valueObject, get an Object that is invokable (i.e. can be the target of an invoke, or
* one of its parms). If it is an array type, the a ValueSender is returned. The invoker needs to
* then cast this to a ValueSender and call the readArray routine.
*/
public Object getInvokableObject(final Commands.ValueObject value) {
switch (value.type) {
case Commands.NEW_OBJECT_ID:
case Commands.OBJECT_ID:
// These need to have access to the server to get the real object
return server.getObject(value.objectID);
default:
// These have all the info needed within the value object itself, so ask it.
return value.getAsObject();
}
}
/**
* Process and loop until told to stop. A callback_done will stop the loop and will return a
* result. Otherwise null is returned.
*/
public Object run() throws CommandException {
Object result = null;
boolean shutdown = false;
boolean closeWhenDone = true;
Commands.ValueObject valueObject =
new Commands.ValueObject(); // Working value object so not continually recreated.
InvokableValueSender valueSender =
new InvokableValueSender(); // Working valuesender so not continually recreated.
try {
boolean doLoop = true;
/**
* Note: In the cases below you will see a lot of finally clauses that null variables out.
* This is because this is a long running loop, and variables declared within blocks are not
* garbage collected until the method is terminated, so these variables once set would never
* be GC'd. The nulling at the end of the case makes sure that any of those objects set are
* now available for garbage collection when necessary.
*/
while (doLoop && isConnected()) {
byte cmd = 0;
try {
if (LINUX_1_3) socket.setSoTimeout(1000); // Linux 1.3 bug, see comment on LINUX_1_3
cmd = in.readByte();
if (LINUX_1_3 && isConnected())
socket.setSoTimeout(0); // Linux 1.3 bug, see comment on LINUX_1_3
} catch (InterruptedIOException e) {
continue; // Timeout, try again
}
switch (cmd) {
case Commands.QUIT_CONNECTION:
doLoop = false;
break; // Close this connection
case Commands.TERMINATE_SERVER:
doLoop = false;
shutdown = true; // Shutdown everything
break;
case Commands.GET_CLASS:
String className = in.readUTF();
Class aClass = null;
Class superClass = null;
String superClassName = null;
boolean added = false;
try {
aClass =
Class.forName(
className); // Turns out using JNI format for array type will work fine.
added = server.getIdentityID(aClass, valueObject);
boolean isInterface = aClass.isInterface();
boolean isAbstract = java.lang.reflect.Modifier.isAbstract(aClass.getModifiers());
superClass = aClass.getSuperclass();
superClassName = (superClass != null) ? superClass.getName() : ""; // $NON-NLS-1$
out.writeByte(Commands.GET_CLASS_RETURN);
out.writeInt(valueObject.objectID);
out.writeBoolean(isInterface);
out.writeBoolean(isAbstract);
out.writeUTF(superClassName);
out.flush();
} catch (ClassNotFoundException e) {
valueObject.set();
Commands.sendErrorCommand(out, Commands.GET_CLASS_NOT_FOUND, valueObject);
} catch (ExceptionInInitializerError e) {
sendException(e.getException(), valueObject, out);
} catch (LinkageError e) {
sendException(e, valueObject, out);
} catch (Throwable e) {
// Something bad, did we add a class? If we did remove it from the table.
if (added) server.removeObject(server.getObject(valueObject.objectID));
throw e;
} finally {
// clear out for GC to work.
className = null;
aClass = null;
superClass = null;
superClassName = null;
valueObject.set();
}
break;
case Commands.GET_CLASS_FROM_ID:
int classID = in.readInt();
try {
aClass = (Class) server.getObject(classID);
boolean isInterface = aClass.isInterface();
boolean isAbstract = java.lang.reflect.Modifier.isAbstract(aClass.getModifiers());
superClass = aClass.getSuperclass();
superClassName = (superClass != null) ? superClass.getName() : ""; // $NON-NLS-1$
out.writeByte(Commands.GET_CLASS_ID_RETURN);
out.writeUTF(aClass.getName());
out.writeBoolean(isInterface);
out.writeBoolean(isAbstract);
out.writeUTF(superClassName);
out.flush();
} catch (ClassCastException e) {
valueObject.set();
Commands.sendErrorCommand(out, Commands.CLASS_CAST_EXCEPTION, valueObject);
} finally {
// clear out for GC to work.
aClass = null;
superClass = null;
superClassName = null;
valueObject.set();
}
break;
case Commands.GET_OBJECT_DATA:
int objectID = in.readInt();
Object anObject = null;
try {
anObject = server.getObject(objectID);
valueObject.setObjectID(objectID, server.getIdentityID(anObject.getClass()));
Commands.writeValue(out, valueObject, true);
} catch (ClassCastException e) {
valueObject.set();
Commands.sendErrorCommand(out, Commands.CLASS_CAST_EXCEPTION, valueObject);
} finally {
anObject = null; // Clear out for GC to work
valueObject.set();
}
break;
case Commands.RELEASE_OBJECT:
int id = in.readInt();
server.removeObject(server.getObject(id));
break;
case Commands.NEW_INIT_STRING:
classID = in.readInt(); // ID Of class to do new upon.
String initString = in.readUTF(); // The init string.
Object newValue = null;
Class theClass = null;
try {
theClass = (Class) server.getObject(classID);
if (theClass == null) {
// The class wasn't found. So imply ClassNotFound exception.
throw new ClassNotFoundException();
}
InitializationStringParser parser = null;
try {
parser = InitializationStringParser.createParser(initString);
newValue = parser.evaluate();
boolean primitive = parser.isPrimitive();
// If expected class is Void.TYPE, that means don't test the type of the result
// to verify if correct type, just return what it really is.
if (theClass != Void.TYPE && primitive != theClass.isPrimitive()) {
valueObject.set();
Commands.sendErrorCommand(out, Commands.CLASS_CAST_EXCEPTION, valueObject);
continue; // Goto next command.
}
if (primitive) {
try {
// Need to do special tests for compatibility and assignment.
sendObject(
newValue,
classID != Commands.VOID_TYPE
? classID
: server.getIdentityID(parser.getExpectedType()),
valueObject,
out,
true); // This will make sure it goes out as the correct primitive type
} catch (ClassCastException e) {
// The returned type is not of the correct type for what is expected.
valueObject.set();
Commands.sendErrorCommand(out, Commands.CLASS_CAST_EXCEPTION, valueObject);
continue; // Goto next command
}
} else {
if (newValue != null) {
// Test to see if they are compatible. (Null can be assigned to any object,
// so that is why it was tested out above).
// If expected class is Void.TYPE, that means don't test the type of the result
// to verify if correct type, just return what it really is.
if (theClass != Void.TYPE && !theClass.isInstance(newValue)) {
// The returned type is not of the correct type for what is expected.
valueObject.set();
Commands.sendErrorCommand(out, Commands.CLASS_CAST_EXCEPTION, valueObject);
continue; // Goto next command
}
}
sendObject(
newValue, NOT_A_PRIMITIVE, valueObject, out, true); // Send out as an object.
}
} catch (InitializationStringEvaluationException e) {
if (e instanceof EvaluationException) {
// Want to return the real exception.
sendException(e.getOriginalException(), valueObject, out);
} else {
// Couldn't be evaluated, return an error for this.
setExceptionIntoValue(e.getOriginalException(), valueObject);
Commands.sendErrorCommand(out, Commands.CANNOT_EVALUATE_STRING, valueObject);
}
} finally {
parser = null; // Clear out for GC to work
}
} catch (Throwable e) {
sendException(e, valueObject, out);
} finally {
// Clear out for GC to work
initString = null;
theClass = null;
newValue = null;
valueObject.set();
}
break;
case Commands.INVOKE:
Object target = null;
Object[] parms = null;
Class returnType = null;
java.lang.reflect.Method aMethod = null;
try {
int methodID = in.readInt(); // ID of method to invoke
aMethod = (java.lang.reflect.Method) server.getObject(methodID); // Method to invoke
Commands.readValue(in, valueObject);
target = getInvokableObject(valueObject);
Commands.readValue(in, valueObject);
if (valueObject.type == Commands.ARRAY_IDS) {
// It is an array containing IDs, as it normally would be.
valueSender.initialize(valueObject);
Commands.readArray(in, valueObject.anInt, valueSender, valueObject, false);
parms = (Object[]) valueSender.getArray();
} else {
// It is all objects or null, so it should be an Object[] or null. If not, then this
// is an error.
parms = (Object[]) valueObject.anObject;
}
if (!aMethod.isAccessible())
aMethod.setAccessible(
true); // We will allow all to occur. Let access control be handled by IDE and
// compiler.
newValue = aMethod.invoke(target, parms);
returnType = aMethod.getReturnType();
if (returnType.isPrimitive()) {
int returnTypeID = server.getIdentityID(returnType);
// Need to tell sendObject the correct primitive type.
sendObject(newValue, returnTypeID, valueObject, out, true);
} else {
sendObject(
newValue,
NOT_A_PRIMITIVE,
valueObject,
out,
true); // Just send the object back. sendObject knows how to iterpret the type
}
} catch (CommandException e) {
throw e; // Throw it again. These we don't want to come up as an exception proxy.
// These should end the thread.
} catch (java.lang.reflect.InvocationTargetException e) {
// This is a wrappered exception. Return the wrappered one so it looks like
// it was the real one. (Sometimes the method being invoked is on a
// java.lang.reflect.Constructor.newInstance,
// which in turn is an InvocationTargetException, so we will go until we don't have an
// InvocationTargetException.
Throwable t = e;
do {
t = ((java.lang.reflect.InvocationTargetException) t).getTargetException();
} while (t instanceof java.lang.reflect.InvocationTargetException);
sendException(t, valueObject, out);
} catch (Throwable e) {
sendException(e, valueObject, out); // Turn it into a exception proxy on the client.
} finally {
// Clear out for GC to work
valueObject.set();
parms = null;
target = null;
aMethod = null;
returnType = null;
newValue = null;
valueSender.clear();
}
break;
case Commands.INVOKE_WITH_METHOD_PASSED:
aClass = null;
String methodName = null;
Class[] parmTypes = null;
target = null;
parms = null;
returnType = null;
aMethod = null;
try {
Commands.readValue(in, valueObject);
aClass = (Class) getInvokableObject(valueObject); // The class that has the method.
methodName = in.readUTF();
Commands.readValue(in, valueObject);
if (valueObject.type == Commands.ARRAY_IDS) {
// It is an array containing IDs, as it normally would be.
valueSender.initialize(valueObject);
Commands.readArray(in, valueObject.anInt, valueSender, valueObject, false);
parmTypes = (Class[]) valueSender.getArray();
} else {
// It null, so it should be an null. If not, then this is an error.
parmTypes = null;
}
aMethod = aClass.getMethod(methodName, parmTypes);
// Now we get the info for the invocation of the method and execute it.
Commands.readValue(in, valueObject);
target = getInvokableObject(valueObject);
Commands.readValue(in, valueObject);
if (valueObject.type == Commands.ARRAY_IDS) {
// It is an array containing IDs, as it normally would be.
valueSender.initialize(valueObject);
Commands.readArray(in, valueObject.anInt, valueSender, valueObject, false);
parms = (Object[]) valueSender.getArray();
} else {
// It is all objects or null, so it should be an Object[] or null. If not, then this
// is an error.
parms = (Object[]) valueObject.anObject;
}
if (!aMethod.isAccessible())
aMethod.setAccessible(
true); // We will allow all to occur. Let access control be handled by IDE and
// compiler.
newValue = aMethod.invoke(target, parms);
returnType = aMethod.getReturnType();
if (returnType.isPrimitive()) {
int returnTypeID = server.getIdentityID(returnType);
// Need to tell sendObject the correct primitive type.
sendObject(newValue, returnTypeID, valueObject, out, true);
} else {
sendObject(
newValue,
NOT_A_PRIMITIVE,
valueObject,
out,
true); // Just send the object back. sendObject knows how to iterpret the type
}
} catch (CommandException e) {
throw e; // Throw it again. These we don't want to come up as an exception proxy.
// These should end the thread.
} catch (java.lang.reflect.InvocationTargetException e) {
// This is a wrappered exception. Return the wrappered one so it looks like
// it was the real one. (Sometimes the method being invoked is on a
// java.lang.reflect.Constructor.newInstance,
// which in turn is an InvocationTargetException, so we will go until we don't have an
// InvocationTargetException.
Throwable t = e;
do {
t = ((java.lang.reflect.InvocationTargetException) t).getTargetException();
} while (t instanceof java.lang.reflect.InvocationTargetException);
sendException(t, valueObject, out);
} catch (Throwable e) {
sendException(e, valueObject, out); // Turn it into a exception proxy on the client.
} finally {
aClass = null;
methodName = null;
parmTypes = null;
// Clear out for GC to work
valueObject.set();
parms = null;
target = null;
aMethod = null;
returnType = null;
newValue = null;
valueSender.clear();
}
break;
case Commands.GET_ARRAY_CONTENTS:
try {
target = server.getObject(in.readInt()); // Array to get the ids for.
valueObject.setArrayIDS(
new ArrayContentsRetriever(target),
Array.getLength(target),
Commands.OBJECT_CLASS);
Commands.writeValue(out, valueObject, true); // Write it back as a value command.
} catch (CommandException e) {
throw e; // Throw it again. These we don't want to come up as an exception proxy.
// These should end the thread.
} catch (Throwable e) {
sendException(e, valueObject, out); // Turn it into a exception proxy on the client.
} finally {
target = null;
valueObject.set();
}
break;
case Commands.CALLBACK_DONE:
try {
if (connectionThread != null) {
valueObject.set();
Commands.sendErrorCommand(out, Commands.UNKNOWN_COMMAND_SENT, valueObject);
} else {
try {
Commands.readBackValue(in, valueObject, Commands.NO_TYPE_CHECK);
if (valueObject.type == Commands.ARRAY_IDS) {
// It is an array containing IDs, as it normally would be.
valueSender.initialize(valueObject);
Commands.readArray(in, valueObject.anInt, valueSender, valueObject, false);
result = valueSender.getArray();
} else {
result = getInvokableObject(valueObject);
}
doLoop = false; // We need to terminate and return result
closeWhenDone = false; // Don't close, we will continue.
} catch (CommandErrorException e) {
// There was an command error on the other side. This means
// connection still good, but don't continue the callback processing.
doLoop = false; // We need to terminate and return result
closeWhenDone = false; // Don't close, we will continue.
throw e; // Let it go on out.
}
}
} finally {
valueObject.set();
valueSender.clear();
}
break;
case Commands.ERROR:
try {
// Got an error command. Don't know what to do but read the
// value and simply print it out.
Commands.readValue(in, valueObject);
result = getInvokableObject(valueObject);
System.out.println("Error sent to server: Result=" + result); // $NON-NLS-1$
} finally {
valueObject.set();
}
break;
case Commands.EXPRESSION_TREE_COMMAND:
try {
processExpressionCommand(valueObject, valueSender);
} finally {
valueObject.set();
valueSender.clear();
}
break;
default:
// Unknown command. We don't know how long it is, so we need to shut the connection
// down.
System.err.println("Error: Invalid cmd send to server: Cmd=" + cmd); // $NON-NLS-1$
doLoop = false;
closeWhenDone = true;
break;
}
}
} catch (EOFException e) {
// This is ok. It means that the connection on the other side was terminated.
// So just accept this and go down.
} catch (CommandException e) {
throw e;
} catch (SocketException e) {
if (socket != null)
throw new UnexpectedExceptionCommandException(
false, e); // socket null means a valid close request
} catch (Throwable e) {
e.printStackTrace();
} finally {
if (closeWhenDone) {
try {
for (Iterator itr = expressionProcessors.values().iterator(); itr.hasNext(); ) {
ExpressionProcesserController exp = (ExpressionProcesserController) itr.next();
exp.close();
}
} finally {
expressionProcessors.clear();
}
if (in != null)
try {
in.close();
} catch (Exception e) {
}
in = null;
if (out != null)
try {
out.close();
} catch (Exception e) {
}
out = null;
close();
}
}
if (closeWhenDone && connectionThread != null) server.removeConnectionThread(connectionThread);
if (shutdown) server.requestShutdown();
return result;
}