Exception from COMBindingBaseObject swallows real reason + HRESULT

CHANGES.md

@@ -68,6 +68,7 @@ Bug Fixes
 * [#610](https://github.com/java-native-access/jna/pull/610): Fixed issue #604: Kernel32#GetLastError() always returns ERROR_SUCCESS [@lgoldstein](https://github.com/lgoldstein).
 * [#633](https://github.com/java-native-access/jna/pull/633): Restore default usage of platform native encoding for Java strings passed to native functions (was hard-coded to UTF-8 in 4.0 and later) [@amake](https://github.com/amake)
 * [#634](https://github.com/java-native-access/jna/pull/634): Improve BSTR handling and add `SysStringByteLen` and `SysStringLen` to `com.sun.jna.platform.win32.OleAuto` - [@matthiasblaesing](https://github.com/matthiasblaesing).
+* [#646](https://github.com/java-native-access/jna/issues/646): `platform.win32.COM.COMBindingBaseObject` swallows reason if instantiation fails - [@matthiasblaesing](https://github.com/matthiasblaesing).
 
 Release 4.2.1
 =============

contrib/platform/src/com/sun/jna/platform/win32/COM/COMBindingBaseObject.java

@@ -15,6 +15,7 @@
 import com.sun.jna.WString;
 import com.sun.jna.platform.win32.Guid;
 import com.sun.jna.platform.win32.Guid.CLSID;
+import com.sun.jna.platform.win32.Guid.GUID;
 import com.sun.jna.platform.win32.Guid.REFIID;
 import com.sun.jna.platform.win32.Kernel32;
 import com.sun.jna.platform.win32.OaIdl;
@@ -74,52 +75,34 @@ public COMBindingBaseObject(CLSID clsid, boolean useActiveInstance,
             int dwClsContext) {
         assert COMUtils.comIsInitialized() : "COM not initialized";
 
-        HRESULT hr;
-
-        if (useActiveInstance) {
-            hr = OleAuto.INSTANCE.GetActiveObject(clsid, null, this.pUnknown);
-
-            if (COMUtils.SUCCEEDED(hr)) {
-                this.iUnknown = new Unknown(this.pUnknown.getValue());
-                hr = iUnknown.QueryInterface(new REFIID( IDispatch.IID_IDISPATCH),
-                        this.pDispatch);
-            } else {
-                hr = Ole32.INSTANCE.CoCreateInstance(clsid, null, dwClsContext,
-                        IDispatch.IID_IDISPATCH, this.pDispatch);
-            }
-        } else {
-            hr = Ole32.INSTANCE.CoCreateInstance(clsid, null, dwClsContext,
-                    IDispatch.IID_IDISPATCH, this.pDispatch);
-        }
-
-        if (COMUtils.FAILED(hr)) {
-            throw new COMException("COM object with CLSID "
-                    + clsid.toGuidString() + " not registered properly!");
-        }
-
-        this.iDispatch = new Dispatch(this.pDispatch.getValue());
+        init(useActiveInstance, clsid, dwClsContext);
     }
 
     public COMBindingBaseObject(String progId, boolean useActiveInstance,
             int dwClsContext) throws COMException {
         assert COMUtils.comIsInitialized() : "COM not initialized";
-
-        HRESULT hr;
 
-        // Get CLSID for Word.Application...
         CLSID.ByReference clsid = new CLSID.ByReference();
-        hr = Ole32.INSTANCE.CLSIDFromProgID(progId, clsid);
+        HRESULT hr = Ole32.INSTANCE.CLSIDFromProgID(progId, clsid);
 
-        if (COMUtils.FAILED(hr)) {
-            throw new COMException("CLSIDFromProgID() failed!");
-        }
+        COMUtils.checkRC(hr);
+
+        init(useActiveInstance, clsid, dwClsContext);
+    }
+
+    public COMBindingBaseObject(String progId, boolean useActiveInstance)
+            throws COMException {
+        this(progId, useActiveInstance, WTypes.CLSCTX_SERVER);
+    }
 
+    private void init(boolean useActiveInstance, GUID clsid, int dwClsContext) throws COMException {
+        HRESULT hr;
         if (useActiveInstance) {
             hr = OleAuto.INSTANCE.GetActiveObject(clsid, null, this.pUnknown);
 
             if (COMUtils.SUCCEEDED(hr)) {
                 this.iUnknown = new Unknown(this.pUnknown.getValue());
-                hr = iUnknown.QueryInterface(new REFIID(IDispatch.IID_IDISPATCH),
+                hr = iUnknown.QueryInterface(new REFIID( IDispatch.IID_IDISPATCH),
                         this.pDispatch);
             } else {
                 hr = Ole32.INSTANCE.CoCreateInstance(clsid, null, dwClsContext,
@@ -129,21 +112,12 @@ public COMBindingBaseObject(String progId, boolean useActiveInstance,
             hr = Ole32.INSTANCE.CoCreateInstance(clsid, null, dwClsContext,
                     IDispatch.IID_IDISPATCH, this.pDispatch);
         }
-
-        if (COMUtils.FAILED(hr)) {
-            throw new COMException("COM object with ProgID '" + progId
-                    + "' and CLSID " + clsid.toGuidString()
-                    + " not registered properly!");
-        }
-
+
+        COMUtils.checkRC(hr);
+
         this.iDispatch = new Dispatch(this.pDispatch.getValue());
     }
-
-    public COMBindingBaseObject(String progId, boolean useActiveInstance)
-            throws COMException {
-        this(progId, useActiveInstance, WTypes.CLSCTX_SERVER);
-    }
-
+
     /**
      * Gets the i dispatch.
      *

contrib/platform/test/com/sun/jna/platform/win32/COM/ComExceptionWithoutInitializationTest.java

@@ -0,0 +1,54 @@
+package com.sun.jna.platform.win32.COM;
+
+import com.sun.jna.platform.win32.Guid;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import org.junit.Test;
+
+public class ComExceptionWithoutInitializationTest {
+
+    @Test
+    public void testCorrectExceptionOnFailedInitialization() {
+        String message = null;
+        try {
+            InternetExplorer ie = new InternetExplorer();
+        } catch (COMException ex) {
+            message = ex.getMessage();
+        }
+
+        // This invocation must raise an exception, as the COM thread is not
+        // initialized, in the message it is expected, that the HRESULT is reported
+        // and the HRESULT resulting from calling into COM with it being initialized
+        // is 800401f0. The message is also expected to point the to correct
+        // initialization via CoInitialize
+        assertNotNull(message);
+        assertTrue(message.contains("HRESULT"));
+        assertTrue(message.contains("800401f0"));
+        assertTrue(message.contains("CoInitialize"));
+    }
+
+    /**
+     * InternetExplorer / IWebBrowser2 - see
+     * http://msdn.microsoft.com/en-us/library/aa752127(v=vs.85).aspx
+     */
+    private static class InternetExplorer extends COMLateBindingObject {
+
+        public InternetExplorer(IDispatch iDispatch) {
+            super(iDispatch);
+        }
+
+        public InternetExplorer() {
+            super(new Guid.CLSID("{0002DF01-0000-0000-C000-000000000046}"), true);
+        }
+
+        /**
+         * IWebBrowser2::get_LocationURL<br>
+         * Read-only COM property.<br>
+         *
+         * @return the URL of the resource that is currently displayed.
+         */
+        public String getURL() {
+            return getStringProperty("LocationURL");
+        }
+    }
+}