/*******************************************************************************
* Copyright 2011 Google Inc. All Rights Reserved.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* 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.gdt.eclipse.designer.ie.jsni;
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;
import com.google.gdt.eclipse.designer.ie.util.Utils;
import com.google.gwt.dev.shell.designtime.DispatchIdOracle;
import com.google.gwt.dev.shell.designtime.JsValueGlue;
/**
* 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.
*/
public 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(ClassLoader cl,
DispatchIdOracle ora,
Class<?> type,
Object o) {
if (type.equals(Variant.class)) {
return (Variant) o;
}
JsValueIE6 jsValue = new JsValueIE6();
JsValueGlue.set(jsValue, cl, ora, type, o);
return jsValue.getVariant();
}
/**
* Converts an array of variants to their equivalent java objects.
*/
public static Object[] convertVariantsToObjects(ClassLoader cl,
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]), cl, 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) {
int length = OS.wcslen(pOleChar);
char[] buffer = new char[length];
OS.MoveMemory(buffer, pOleChar, length * 2);
return String.valueOf(buffer);
}
/**
* Injects an object into the Browser class that resolves to IE's 'window.external' object.
*/
public static void injectBrowserScriptExternalObject(Browser browser, final IDispatchImpl external) {
COMObject iDocHostUIHandler = getDocHostUIHandler(browser);
// 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();
}
@Override
public int method15(int[] args) {
// GetExternal() is method 15.
//
return GetExternal(args[0]);
}
@Override
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);
}
public static void ejectBrowserScriptExternalObject(Browser browser) {
COMObject iDocHostUIHandler = getDocHostUIHandler(browser);
COMObjectProxy.setCOMObject(iDocHostUIHandler.getAddress(), iDocHostUIHandler);
}
/**
* Helper method to obtain <code>iDocHostUIHandler</code> instance.
*/
private static COMObject getDocHostUIHandler(Browser browser) {
// Grab the browser's 'site.iDocHostUIHandler' field.
//
Object webBrowser = Utils.getFieldObjectValue(browser, "webBrowser");
Object webSite = Utils.getFieldObjectValue(webBrowser, "site");
return (COMObject) Utils.getFieldObjectValue(webSite, "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) {
if (s.length() != 0) {
return COM.SysAllocString((s + "\0").toCharArray());
}
return 0;
// return COM.SysAllocStringLen(s.toCharArray(), s.length());
}
}