speed-up: preload JVM when PreloadJVM is set

Change-Id: I57f77f127f7cb45fb181b755b40873d47015e5b2
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/91059
Tested-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>

3 files changed, 62 insertions, 1 deletions

diff --git a/desktop/source/app/app.cxx b/desktop/source/app/app.cxx
index 6e067efad529..dd38a74aa89e 100644
--- a/desktop/source/app/app.cxx
+++ b/desktop/source/app/app.cxx
@@ -74,6 +74,7 @@
 #include <com/sun/star/office/Quickstart.hpp>
 #include <com/sun/star/system/XSystemShellExecute.hpp>
 #include <com/sun/star/system/SystemShellExecute.hpp>
+#include <com/sun/star/loader/XImplementationLoader.hpp>
 
 #include <desktop/exithelper.h>
 #include <sal/log.hxx>
@@ -120,6 +121,7 @@
 #include <vcl/graphicfilter.hxx>
 #include <vcl/window.hxx>
 #include "langselect.hxx"
+#include <salhelper/thread.hxx>
 
 #if defined MACOSX
 #include <errno.h>
@@ -1173,6 +1175,36 @@ void Desktop::AppEvent( const ApplicationEvent& rAppEvent )
 
 namespace {
 
+class JVMloadThread : public salhelper::Thread {
+public:
+    JVMloadThread() : salhelper::Thread("Preload JVM thread")
+    {
+    }
+
+private:
+    virtual void execute() override final
+    {
+        Reference< XMultiServiceFactory > xSMgr = comphelper::getProcessServiceFactory();
+
+        Reference< css::loader::XImplementationLoader > xJavaComponentLoader(
+            xSMgr->createInstance("com.sun.star.comp.stoc.JavaComponentLoader"),
+            css::uno::UNO_QUERY_THROW);
+
+        if (xJavaComponentLoader.is())
+        {
+            const css::uno::Reference< ::com::sun::star::registry::XRegistryKey > xRegistryKey;
+            try
+            {
+                xJavaComponentLoader->activate("", "", "", xRegistryKey);
+            }
+            catch (...)
+            {
+                SAL_WARN("desktop.app", "Cannot activate factory during JVM preloading");
+            }
+        }
+    }
+};
+
 struct ExecuteGlobals
 {
     Reference < css::document::XDocumentEventListener > xGlobalBroadcaster;
@@ -1180,6 +1212,7 @@ struct ExecuteGlobals
     bool bUseSystemFileDialog;
     std::unique_ptr<SvtLanguageOptions> pLanguageOptions;
     std::unique_ptr<SvtPathOptions> pPathOptions;
+    rtl::Reference< JVMloadThread > xJVMloadThread;
 
     ExecuteGlobals()
     : bRestartRequested( false )
@@ -1212,6 +1245,15 @@ int Desktop::Main()
     // Detect desktop environment - need to do this as early as possible
     css::uno::setCurrentContext( new DesktopContext( css::uno::getCurrentContext() ) );
 
+    if (officecfg::Office::Common::Misc::PreloadJVM::get() && pExecGlobals)
+    {
+        SAL_INFO("desktop.app", "Preload JVM");
+
+        // pre-load JVM
+        pExecGlobals->xJVMloadThread = new JVMloadThread();
+        pExecGlobals->xJVMloadThread->launch();
+    }
+
     CommandLineArgs& rCmdLineArgs = GetCommandLineArgs();
 
     Translate::SetReadStringHook(ReplaceStringHookProc);
@@ -1566,6 +1608,12 @@ int Desktop::doShutdown()
     if (m_aUpdateThread.joinable())
         m_aUpdateThread.join();
 
+    if (pExecGlobals->xJVMloadThread.is())
+    {
+        pExecGlobals->xJVMloadThread->join();
+        pExecGlobals->xJVMloadThread.clear();
+    }
+
     pExecGlobals->bRestartRequested = pExecGlobals->bRestartRequested ||
         OfficeRestartManager::get(comphelper::getProcessComponentContext())->
         isRestartRequested(true);
diff --git a/officecfg/registry/schema/org/openoffice/Office/Common.xcs b/officecfg/registry/schema/org/openoffice/Office/Common.xcs
index 048f64ab3f18..f764d3d7aa45 100644
--- a/officecfg/registry/schema/org/openoffice/Office/Common.xcs
+++ b/officecfg/registry/schema/org/openoffice/Office/Common.xcs
@@ -5824,6 +5824,13 @@
         </info>
         <value>true</value>
       </prop>
+      <prop oor:name="PreloadJVM" oor:type="xs:boolean" oor:nillable="false">
+        <info>
+          <desc>Specifies if the JVM should be preloaded during LO start up.</desc>
+          <label>PreloadJVM</label>
+        </info>
+        <value>false</value>
+      </prop>
       <prop oor:name="FilePickerPlacesUrls" oor:type="oor:string-list" oor:nillable="false">
         <info>
           <desc>List of URLs of the places the user bookmarked in the file picker dialog.</desc>
diff --git a/stoc/source/javaloader/javaloader.cxx b/stoc/source/javaloader/javaloader.cxx
index 2b40cdd219db..73b0ddf557ff 100644
--- a/stoc/source/javaloader/javaloader.cxx
+++ b/stoc/source/javaloader/javaloader.cxx
@@ -304,11 +304,17 @@ sal_Bool SAL_CALL JavaComponentLoader::writeRegistryInfo(
     return loader->writeRegistryInfo(xKey, blabla, rLibName);
 }
 
-
 css::uno::Reference<XInterface> SAL_CALL JavaComponentLoader::activate(
     const OUString & rImplName, const OUString & blabla, const OUString & rLibName,
     const css::uno::Reference<XRegistryKey> & xKey)
 {
+    if (rImplName.isEmpty() && blabla.isEmpty() && rLibName.isEmpty())
+    {
+        // preload JVM was requested
+        (void)getJavaLoader();
+        return css::uno::Reference<XInterface>();
+    }
+
     const css::uno::Reference<XImplementationLoader> & loader = getJavaLoader();
     if (!loader.is())
         throw CannotActivateFactoryException("Could not create Java implementation loader");