/*
* Copyright 2006 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.dev.shell.ie;
import com.google.gwt.dev.shell.CompilingClassLoader;
import com.google.gwt.dev.shell.JsValueGlue;
import com.google.gwt.dev.shell.LowLevel;
import org.eclipse.swt.browser.Browser;
import org.eclipse.swt.internal.ole.win32.COM;
import org.eclipse.swt.internal.ole.win32.COMObject;
import org.eclipse.swt.internal.win32.OS;
import org.eclipse.swt.ole.win32.Variant;
/**
* A bag of static helper methods for mucking about with low-level SWT and COM
* constructs. Much of this is necessary simply to do things that the SWT
* implementers weren't really thinking about when they wrote the COM layer.
*/
class SwtOleGlue {
/**
* Converts a java object to its equivalent variant. A ClassLoader is passed
* here so that Handles can be manipulated properly.
*/
public static Variant convertObjectToVariant(CompilingClassLoader cl,
Class type, Object o) {
if (type.equals(Variant.class)) {
return (Variant) o;
}
JsValueIE6 jsValue = new JsValueIE6();
JsValueGlue.set(jsValue, cl, type, o);
return jsValue.getVariant();
}
/**
* Converts an array of variants to their equivalent java objects.
*/
public static Object[] convertVariantsToObjects(Class[] argTypes,
Variant[] varArgs, String msgPrefix) {
Object[] javaArgs = new Object[Math.min(varArgs.length, argTypes.length)];
for (int i = 0; i < javaArgs.length; i++) {
try {
Object javaArg = JsValueGlue.get(new JsValueIE6(varArgs[i]),
argTypes[i], msgPrefix);
javaArgs[i] = javaArg;
} catch (IllegalArgumentException e) {
throw new IllegalArgumentException("Error converting argument "
+ (i + 1) + ": " + e.getMessage());
}
}
return javaArgs;
}
/**
* Extracts an array of strings from an (OLECHAR**) type (useful for
* implementing GetIDsOfNames()).
*/
public static String[] extractStringArrayFromOleCharPtrPtr(int ppchar,
int count) {
String[] strings = new String[count];
for (int i = 0; i < count; ++i) {
int[] pchar = new int[1];
OS.MoveMemory(pchar, ppchar + 4 * i, 4);
strings[i] = extractStringFromOleCharPtr(pchar[0]);
}
return strings;
}
/**
* Extracts a string from an (OLECHAR*) type.
*/
public static String extractStringFromOleCharPtr(int pOleChar) {
// TODO: double-check the encoding (is it UTF-16?, what)
int size = COM.SysStringByteLen(pOleChar);
if (size > 8192) {
size = 8192;
}
char[] buffer = new char[(size + 1) / 2];
COM.MoveMemory(buffer, pOleChar, size);
String s = new String(buffer);
if (s.indexOf('\0') != -1) {
return s.substring(0, s.indexOf('\0'));
} else {
return s;
}
}
/**
* Injects an object into the Browser class that resolves to IE's
* 'window.external' object.
*/
public static void injectBrowserScriptExternalObject(Browser browser,
final IDispatchImpl external) {
// Grab the browser's 'site.iDocHostUIHandler' field.
//
Object webSite = LowLevel.snatchFieldObjectValue(browser, "site");
COMObject iDocHostUIHandler = (COMObject) LowLevel.snatchFieldObjectValue(
webSite, "iDocHostUIHandler");
// Create a COMObjectProxy that will override GetExternal().
//
COMObjectProxy webSiteProxy = new COMObjectProxy(new int[] {
2, 0, 0, 4, 1, 5, 0, 0, 1, 1, 1, 3, 3, 2, 2, 1, 3, 2}) {
{
// make sure we hold onto a ref on the external object
external.AddRef();
}
public int method15(int[] args) {
// GetExternal() is method 15.
//
return GetExternal(args[0]);
}
public int method2(int[] args) {
int result = super.method2(args);
if (result == 0) {
external.Release();
}
return result;
}
// CHECKSTYLE_OFF
int GetExternal(int ppDispatch) {
// CHECKSTYLE_ON
if (ppDispatch != 0) {
try {
// Return the 'external' object.
//
external.AddRef();
OS.MoveMemory(ppDispatch, new int[] {external.getAddress()}, 4);
return COM.S_OK;
} catch (Throwable e) {
e.printStackTrace();
return COM.E_FAIL;
}
} else {
OS.MoveMemory(ppDispatch, new int[] {0}, 4);
return COM.E_NOTIMPL;
}
}
};
// Interpose the proxy in front of the browser's iDocHostUiHandler.
//
webSiteProxy.interpose(iDocHostUIHandler);
}
/**
* Convert a Java string to a COM BSTR.
*
* Wrapper for the OS' SysAllocStringLen(), since SysAllocString() is not
* safe for embedded nulls.
*/
public static int sysAllocString(String s) {
return COM.SysAllocStringLen(s.toCharArray(), s.length());
}
}