Class JreCompat

  • Direct Known Subclasses:
    Jre12Compat

    public class JreCompat
    extends java.lang.Object
    This is the base implementation class for JRE compatibility and provides an implementation based on Java 8. Subclasses may extend this class and provide alternative implementations for later JRE versions
    • Field Detail

      • USE_CANON_CACHES_CMD_ARG

        protected static final java.lang.String USE_CANON_CACHES_CMD_ARG
        See Also:
        Constant Field Values
      • canonCachesDisabled

        protected static volatile java.lang.Boolean canonCachesDisabled
      • canonCachesDisabledLock

        protected static final java.lang.Object canonCachesDisabledLock
      • useCanonCachesField

        protected static volatile java.util.Optional<java.lang.reflect.Field> useCanonCachesField
      • useCanonCachesFieldLock

        protected static final java.lang.Object useCanonCachesFieldLock
      • setApplicationProtocolsMethod

        protected static final java.lang.reflect.Method setApplicationProtocolsMethod
      • getApplicationProtocolMethod

        protected static final java.lang.reflect.Method getApplicationProtocolMethod
    • Constructor Detail

      • JreCompat

        public JreCompat()
    • Method Detail

      • getInstance

        public static JreCompat getInstance()
      • isGraalAvailable

        public static boolean isGraalAvailable()
      • isAlpnSupported

        public static boolean isAlpnSupported()
      • isJre9Available

        public static boolean isJre9Available()
      • isJre11Available

        public static boolean isJre11Available()
      • isJre12Available

        public static boolean isJre12Available()
      • isJre16Available

        public static boolean isJre16Available()
      • isJre19Available

        public static boolean isJre19Available()
      • isJre21Available

        public static boolean isJre21Available()
      • isJre22Available

        public static boolean isJre22Available()
      • isInstanceOfInaccessibleObjectException

        public boolean isInstanceOfInaccessibleObjectException​(java.lang.Throwable t)
        Test if the provided exception is an instance of java.lang.reflect.InaccessibleObjectException.
        Parameters:
        t - The exception to test
        Returns:
        true if the exception is an instance of InaccessibleObjectException, otherwise false
      • setApplicationProtocols

        public void setApplicationProtocols​(javax.net.ssl.SSLParameters sslParameters,
                                            java.lang.String[] protocols)
        Set the application protocols the server will accept for ALPN
        Parameters:
        sslParameters - The SSL parameters for a connection
        protocols - The application protocols to be allowed for that connection
      • getApplicationProtocol

        public java.lang.String getApplicationProtocol​(javax.net.ssl.SSLEngine sslEngine)
        Get the application protocol that has been negotiated for connection associated with the given SSLEngine.
        Parameters:
        sslEngine - The SSLEngine for which to obtain the negotiated protocol
        Returns:
        The name of the negotiated protocol
      • disableCachingForJarUrlConnections

        public void disableCachingForJarUrlConnections()
                                                throws java.io.IOException
        Disables caching for JAR URL connections. For Java 8 and earlier, this also disables caching for ALL URL connections.
        Throws:
        java.io.IOException - If a dummy JAR URLConnection can not be created
      • addBootModulePath

        public void addBootModulePath​(java.util.Deque<java.net.URL> classPathUrlsToProcess)
        Obtains the URLs for all the JARs on the module path when the JVM starts and adds them to the provided Deque.
        Parameters:
        classPathUrlsToProcess - The Deque to which the modules should be added
      • jarFileNewInstance

        public final java.util.jar.JarFile jarFileNewInstance​(java.lang.String s)
                                                       throws java.io.IOException
        Creates a new JarFile instance. When running on Java 9 and later, the JarFile will be multi-release JAR aware. While this isn't strictly required to be in this package, it is provided as a convenience method.
        Parameters:
        s - The JAR file to open
        Returns:
        A JarFile instance based on the provided path
        Throws:
        java.io.IOException - If an I/O error occurs creating the JarFile instance
      • jarFileNewInstance

        public java.util.jar.JarFile jarFileNewInstance​(java.io.File f)
                                                 throws java.io.IOException
        Creates a new JarFile instance. When running on Java 9 and later, the JarFile will be multi-release JAR aware.
        Parameters:
        f - The JAR file to open
        Returns:
        A JarFile instance based on the provided file
        Throws:
        java.io.IOException - If an I/O error occurs creating the JarFile instance
      • jarFileIsMultiRelease

        public boolean jarFileIsMultiRelease​(java.util.jar.JarFile jarFile)
        Is this JarFile a multi-release JAR file.
        Parameters:
        jarFile - The JarFile to test
        Returns:
        true If it is a multi-release JAR file and is configured to behave as such.
      • jarFileRuntimeMajorVersion

        public int jarFileRuntimeMajorVersion()
      • canAccess

        public boolean canAccess​(java.lang.Object base,
                                 java.lang.reflect.AccessibleObject accessibleObject)
        Is the accessibleObject accessible (as a result of appropriate module exports) on the provided instance?
        Parameters:
        base - The specific instance to be tested.
        accessibleObject - The method/field/constructor to be tested.
        Returns:
        {code true} if the AccessibleObject can be accessed otherwise {code false}
      • isExported

        public boolean isExported​(java.lang.Class<?> type)
        Is the given class in an exported package?
        Parameters:
        type - The class to test
        Returns:
        Always true for Java 8. true if the enclosing package is exported for Java 9+
      • getModuleName

        public java.lang.String getModuleName​(java.lang.Class<?> type)
        What is the module of the given class?
        Parameters:
        type - The class to test
        Returns:
        Always true for Java 8. true if the enclosing package is exported for Java 9+
      • getUnixDomainSocketAddress

        public java.net.SocketAddress getUnixDomainSocketAddress​(java.lang.String path)
        Return Unix domain socket address for given path.
        Parameters:
        path - The path
        Returns:
        the socket address
      • openUnixDomainServerSocketChannel

        public java.nio.channels.ServerSocketChannel openUnixDomainServerSocketChannel()
        Create server socket channel using the Unix domain socket ProtocolFamily.
        Returns:
        the server socket channel
      • openUnixDomainSocketChannel

        public java.nio.channels.SocketChannel openUnixDomainSocketChannel()
        Create socket channel using the Unix domain socket ProtocolFamily.
        Returns:
        the socket channel
      • getExecutor

        public java.lang.Object getExecutor​(java.lang.Thread thread)
                                     throws java.lang.NoSuchFieldException,
                                            java.lang.SecurityException,
                                            java.lang.IllegalArgumentException,
                                            java.lang.IllegalAccessException
        Obtains the executor, if any, used to create the provided thread.
        Parameters:
        thread - The thread to examine
        Returns:
        The executor, if any, that created the provided thread
        Throws:
        java.lang.NoSuchFieldException - If a field used via reflection to obtain the executor cannot be found
        java.lang.SecurityException - If a security exception occurs while trying to identify the executor
        java.lang.IllegalArgumentException - If the instance object does not match the class of the field when obtaining a field value via reflection
        java.lang.IllegalAccessException - If a field is not accessible due to access restrictions
      • createVirtualThreadBuilder

        public java.lang.Object createVirtualThreadBuilder​(java.lang.String name)
        Create a thread builder for virtual threads using the given name to name the threads.
        Parameters:
        name - The base name for the threads
        Returns:
        The thread buidler for virtual threads
      • threadBuilderStart

        public void threadBuilderStart​(java.lang.Object threadBuilder,
                                       java.lang.Runnable command)
        Create a thread with the given thread builder and use it to execute the given runnable.
        Parameters:
        threadBuilder - The thread builder to use to create a thread
        command - The command to run
      • callAs

        public <T> T callAs​(javax.security.auth.Subject subject,
                            java.util.concurrent.Callable<T> action)
                     throws java.util.concurrent.CompletionException
        Throws:
        java.util.concurrent.CompletionException
      • isCanonCachesDisabled

        public boolean isCanonCachesDisabled()
      • disableCanonCaches

        public boolean disableCanonCaches()
        Disable the global canonical file cache.
        Returns:
        true if the global canonical file cache was already disabled prior to this call or was disabled as a result of this call, otherwise false
      • ensureUseCanonCachesFieldIsPopulated

        protected void ensureUseCanonCachesFieldIsPopulated()