1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package jdk.vm.ci.runtime;
  24 
  25 import java.util.Formatter;
  26 



  27 public class JVMCI {
  28 
  29     private static final JVMCIRuntime runtime;



  30 
  31     private static native JVMCIRuntime initializeRuntime();
  32 
  33     public static void initialize() {
  34         // force static initializer
  35     }
  36 


  37     /**
  38      * Gets the singleton {@link JVMCIRuntime} instance available to the application.
  39      *
  40      * @throws UnsupportedOperationException if JVMCI is not supported
  41      */
  42     public static JVMCIRuntime getRuntime() {
  43         if (runtime == null) {
  44             String javaHome = System.getProperty("java.home");
  45             String vmName = System.getProperty("java.vm.name");















  46             Formatter errorMessage = new Formatter();
  47             errorMessage.format("The VM does not support the JVMCI API.%n");
  48             errorMessage.format("Currently used Java home directory is %s.%n", javaHome);
  49             errorMessage.format("Currently used VM configuration is: %s", vmName);
  50             throw new UnsupportedOperationException(errorMessage.toString());
  51         }
  52         return runtime;
  53     }
  54 
  55     static {
  56         JVMCIRuntime rt = null;
  57         try {
  58             rt = initializeRuntime();
  59         } catch (UnsatisfiedLinkError e) {
  60         }
  61         runtime = rt;

  62     }
  63 }

   1 /*
   2  * Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package jdk.vm.ci.runtime;
  24 
  25 import java.util.Formatter;
  26 
  27 import jdk.vm.ci.common.NativeImageReinitialize;
  28 import jdk.vm.ci.services.Services;
  29 
  30 public class JVMCI {
  31 
  32     /**
  33      * Singleton instance lazily initialized via double-checked locking.
  34      */
  35     @NativeImageReinitialize private static volatile JVMCIRuntime runtime;
  36 
  37     @NativeImageReinitialize private static boolean initializing;
  38 
  39     public static void initialize() {
  40         // force static initializer
  41     }
  42 
  43     private static native JVMCIRuntime initializeRuntime();
  44 
  45     /**
  46      * Gets the singleton {@link JVMCIRuntime} instance available to the application.
  47      *
  48      * @throws UnsupportedOperationException if JVMCI is not supported
  49      */
  50     public static JVMCIRuntime getRuntime() {
  51         JVMCIRuntime result = runtime;
  52         if (result == null) {
  53             synchronized (JVMCI.class) {
  54                 result = runtime;
  55                 if (result == null) {
  56                     if (initializing) {
  57                         // In recursive call from HotSpotJVMCIRuntime.runtime
  58                         // so no need to re-enter initializeRuntime below. This
  59                         // path is only entered if JVMCI initialization starts
  60                         // with JVMCI.getRuntime().
  61                         return null;
  62                     }
  63                     initializing = true;
  64                     try {
  65                         runtime = result = initializeRuntime();
  66                     } catch (UnsatisfiedLinkError e) {
  67                         String javaHome = Services.getSavedProperty("java.home");
  68                         String vmName = Services.getSavedProperty("java.vm.name");
  69                         Formatter errorMessage = new Formatter();
  70                         errorMessage.format("The VM does not support the JVMCI API.%n");
  71                         errorMessage.format("Currently used Java home directory is %s.%n", javaHome);
  72                         errorMessage.format("Currently used VM configuration is: %s", vmName);
  73                         throw new UnsupportedOperationException(errorMessage.toString());
  74                     }

  75                 }






  76             }
  77         }
  78         return result;
  79     }
  80 }