jdk/src/java.management/share/classes/sun/management/ManagementFactoryHelper.java

*** 37,50 ****
  import java.security.PrivilegedActionException;
  import java.security.PrivilegedExceptionAction;
  
  import jdk.internal.misc.JavaNioAccess;
  import jdk.internal.misc.SharedSecrets;
! import sun.util.logging.LoggingSupport;
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * ManagementFactoryHelper provides static factory methods to create
   * instances of the management interface.
   */
  public class ManagementFactoryHelper {
--- 37,54 ----
  import java.security.PrivilegedActionException;
  import java.security.PrivilegedExceptionAction;
  
  import jdk.internal.misc.JavaNioAccess;
  import jdk.internal.misc.SharedSecrets;
! 
  import java.util.ArrayList;
  import java.util.List;
  
+ import java.lang.reflect.Constructor;
+ import java.lang.reflect.InvocationTargetException;
+ import java.security.PrivilegedAction;
+ 
  /**
   * ManagementFactoryHelper provides static factory methods to create
   * instances of the management interface.
   */
  public class ManagementFactoryHelper {
*** 139,155 ****
          }
          return result;
      }
  
      public static PlatformLoggingMXBean getPlatformLoggingMXBean() {
!         if (LoggingSupport.isAvailable()) {
              return PlatformLoggingImpl.instance;
          } else {
              return null;
          }
      }
  
      /**
       * The logging MXBean object is an instance of
       * PlatformLoggingMXBean and java.util.logging.LoggingMXBean
       * but it can't directly implement two MXBean interfaces
       * as a compliant MXBean implements exactly one MXBean interface,
--- 143,163 ----
          }
          return result;
      }
  
      public static PlatformLoggingMXBean getPlatformLoggingMXBean() {
!         if (LoggingMXBeanSupport.isAvailable()) {
              return PlatformLoggingImpl.instance;
          } else {
              return null;
          }
      }
  
+     public static boolean isPlatformLoggingMXBeanAvailable() {
+         return LoggingMXBeanSupport.isAvailable();
+     }
+ 
      /**
       * The logging MXBean object is an instance of
       * PlatformLoggingMXBean and java.util.logging.LoggingMXBean
       * but it can't directly implement two MXBean interfaces
       * as a compliant MXBean implements exactly one MXBean interface,
*** 163,174 ****
--- 171,218 ----
      */
      public interface LoggingMXBean
          extends PlatformLoggingMXBean, java.util.logging.LoggingMXBean {
      }
  
+     // This is a trick: if java.util.logging is not present then
+     // attempting to access something that implements
+     // java.util.logging.LoggingMXBean will trigger a CNFE.
+     // So we cannot directly call any static method or access any static field
+     // on PlatformLoggingImpl, as we would risk raising a CNFE.
+     // Instead we use this intermediate LoggingMXBeanSupport class to determine
+     // whether java.util.logging is present, and load the actual LoggingMXBean
+     // implementation.
+     //
+     static final class LoggingMXBeanSupport {
+         final static Object loggingImpl =
+                 AccessController.doPrivileged(new PrivilegedAction<Object>() {
+             @Override
+             public Object run() {
+                 try {
+                     // create a LoggingProxyImpl instance when
+                     // java.util.logging classes exist
+                     Class<?> c = Class.forName("java.util.logging.Logging", true, null);
+                     Constructor<?> cons = c.getDeclaredConstructor();
+                     cons.setAccessible(true);
+                     return cons.newInstance();
+                 } catch (ClassNotFoundException cnf) {
+                     return null;
+                 } catch (NoSuchMethodException | InstantiationException
+                         | IllegalAccessException | InvocationTargetException e) {
+                     throw new AssertionError(e);
+                 }
+             }});
+ 
+         static boolean isAvailable() {
+             return loggingImpl != null;
+         }
+     }
+ 
      static class PlatformLoggingImpl implements LoggingMXBean
      {
+         final static java.util.logging.LoggingMXBean impl =
+                 (java.util.logging.LoggingMXBean) LoggingMXBeanSupport.loggingImpl;
          final static PlatformLoggingMXBean instance = new PlatformLoggingImpl();
          final static String LOGGING_MXBEAN_NAME = "java.util.logging:type=Logging";
  
          private volatile ObjectName objname;  // created lazily
          @Override
*** 186,211 ****
              return result;
          }
  
          @Override
          public java.util.List<String> getLoggerNames() {
!             return LoggingSupport.getLoggerNames();
          }
  
          @Override
          public String getLoggerLevel(String loggerName) {
!             return LoggingSupport.getLoggerLevel(loggerName);
          }
  
          @Override
          public void setLoggerLevel(String loggerName, String levelName) {
!             LoggingSupport.setLoggerLevel(loggerName, levelName);
          }
  
          @Override
          public String getParentLoggerName(String loggerName) {
!             return LoggingSupport.getParentLoggerName(loggerName);
          }
      }
  
      private static List<BufferPoolMXBean> bufferPools = null;
      public static synchronized List<BufferPoolMXBean> getBufferPoolMXBeans() {
--- 230,255 ----
              return result;
          }
  
          @Override
          public java.util.List<String> getLoggerNames() {
!             return impl.getLoggerNames();
          }
  
          @Override
          public String getLoggerLevel(String loggerName) {
!             return impl.getLoggerLevel(loggerName);
          }
  
          @Override
          public void setLoggerLevel(String loggerName, String levelName) {
!             impl.setLoggerLevel(loggerName, levelName);
          }
  
          @Override
          public String getParentLoggerName(String loggerName) {
!             return impl.getParentLoggerName(loggerName);
          }
      }
  
      private static List<BufferPoolMXBean> bufferPools = null;
      public static synchronized List<BufferPoolMXBean> getBufferPoolMXBeans() {