jvmaccess/source/virtualmachine.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <sal/config.h>
  21
  22 #include <cassert>
  23
  24 #include <jvmaccess/virtualmachine.hxx>
  25 #include <sal/log.hxx>
  26 #include <utility>
  27
  28 using jvmaccess::VirtualMachine;
  29
  30 VirtualMachine::AttachGuard::CreationException::CreationException()
  31 {}
  32
  33 VirtualMachine::AttachGuard::CreationException::CreationException(
  34     CreationException const &)
  35 {}
  36
  37 VirtualMachine::AttachGuard::CreationException &
  38 VirtualMachine::AttachGuard::CreationException::operator =(
  39     CreationException const &)
  40 {
  41     return *this;
  42 }
  43
  44 VirtualMachine::AttachGuard::AttachGuard(
  45     rtl::Reference< VirtualMachine > xMachine):
  46     m_xMachine(std::move(xMachine))
  47 {
  48     assert(m_xMachine.is());
  49     m_pEnvironment = m_xMachine->attachThread(&m_bDetach);
  50     if (m_pEnvironment == nullptr)
  51         throw CreationException();
  52 }
  53
  54 VirtualMachine::AttachGuard::~AttachGuard()
  55 {
  56     if (m_bDetach)
  57         m_xMachine->detachThread();
  58 }
  59
  60 VirtualMachine::VirtualMachine(JavaVM * pVm, int nVersion, bool bDestroy,
  61                                JNIEnv const * pMainThreadEnv):
  62     m_pVm(pVm), m_nVersion(nVersion), m_bDestroy(bDestroy)
  63 {
  64     (void) pMainThreadEnv; // avoid warnings
  65     assert(pVm != nullptr);
  66     assert(nVersion >= JNI_VERSION_1_2);
  67     assert(pMainThreadEnv);
  68 }
  69
  70 VirtualMachine::~VirtualMachine()
  71 {
  72     if (m_bDestroy)
  73     {
  74         // Do not destroy the VM.  Under Java 1.3, the AWT event loop thread is
  75         // not a daemon thread and is never terminated, so that calling
  76         // DestroyJavaVM (waiting for all non-daemon threads to terminate) hangs
  77         // forever.
  78 /*
  79         jint n = m_pVm->DestroyJavaVM();
  80         SAL_WARN_IF(n != JNI_OK, "jvmaccess", "JNI: DestroyJavaVM failed");
  81 */
  82     }
  83 }
  84
  85 JNIEnv * VirtualMachine::attachThread(bool * pAttached) const
  86 {
  87     assert(pAttached != nullptr && "bad parameter");
  88     JNIEnv * pEnv;
  89     jint n = m_pVm->GetEnv(reinterpret_cast< void ** >(&pEnv), m_nVersion);
  90     SAL_WARN_IF(
  91         n != JNI_OK && n != JNI_EDETACHED, "jvmaccess", "JNI: GetEnv failed");
  92     if (pEnv == nullptr)
  93     {
  94         if (m_pVm->AttachCurrentThread
  95             (
  96 #ifndef ANDROID
  97              reinterpret_cast< void ** >(&pEnv),
  98 #else
  99              // The Android <jni.h> has AttachCurrentThread() taking a
 100              // JNIEnv** and not void **
 101              &pEnv,
 102 #endif
 103              nullptr)
 104             != JNI_OK)
 105             return nullptr;
 106         *pAttached = true;
 107     }
 108     else
 109         *pAttached = false;
 110     return pEnv;
 111 }
 112
 113 void VirtualMachine::detachThread() const
 114 {
 115     jint n = m_pVm->DetachCurrentThread();
 116     SAL_WARN_IF(n != JNI_OK, "jvmaccess", "JNI: DetachCurrentThread failed");
 117 }
 118
 119 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */