Class Util


  • public final class Util
    extends Object
    General utility methods used throughout the Infinispan code base.
    Since:
    4.0
    Author:
    Brian Stansberry, Galder ZamarreƱo
    • Field Detail

      • EMPTY_OBJECT_ARRAY

        public static final Object[] EMPTY_OBJECT_ARRAY
      • EMPTY_STRING_ARRAY

        public static final String[] EMPTY_STRING_ARRAY
      • EMPTY_BYTE_ARRAY

        public static final byte[] EMPTY_BYTE_ARRAY
      • EMPTY_BYTE_ARRAY_ARRAY

        public static final byte[][] EMPTY_BYTE_ARRAY_ARRAY
    • Method Detail

      • loadClass

        public static <T> Class<T> loadClass​(String classname,
                                             ClassLoader cl)

        Loads the specified class using the passed classloader, or, if it is null the Infinispan classes' classloader.

        If loadtime instrumentation via GenerateInstrumentedClassLoader is used, this class may be loaded by the bootstrap classloader.

        If the class is not found, the ClassNotFoundException or NoClassDefFoundError is wrapped as a CacheConfigurationException and is re-thrown.

        Parameters:
        classname - name of the class to load
        cl - the application classloader which should be used to load the class, or null if the class is always packaged with Infinispan
        Returns:
        the class
        Throws:
        CacheConfigurationException - if the class cannot be loaded
      • isOSGiContext

        public static boolean isOSGiContext()
        Tries to determine if the code is running in an OSGi context.
        Returns:
        true if an OSGi context is detected
      • loadClassStrict

        public static <T> Class<T> loadClassStrict​(String classname,
                                                   ClassLoader userClassLoader)
                                            throws ClassNotFoundException

        Loads the specified class using the passed classloader, or, if it is null the Infinispan classes' classloader.

        If loadtime instrumentation via GenerateInstrumentedClassLoader is used, this class may be loaded by the bootstrap classloader.

        Parameters:
        classname - name of the class to load
        userClassLoader - the application classloader which should be used to load the class, or null if the class is always packaged with Infinispan
        Returns:
        the class
        Throws:
        ClassNotFoundException - if the class cannot be loaded
      • getInstance

        public static <T> T getInstance​(Class<T> clazz)
        Instantiates a class by first attempting a static factory method named getInstance() on the class and then falling back to an empty constructor.

        Any exceptions encountered are wrapped in a CacheConfigurationException and rethrown.

        Parameters:
        clazz - class to instantiate
        Returns:
        an instance of the class
      • getInstance

        public static <T> T getInstance​(String classname,
                                        ClassLoader cl)
        Instantiates a class based on the class name provided. Instantiation is attempted via an appropriate, static factory method named getInstance() first, and failing the existence of an appropriate factory, falls back to an empty constructor.

        Any exceptions encountered loading and instantiating the class is wrapped in a CacheConfigurationException.

        Parameters:
        classname - class to instantiate
        Returns:
        an instance of classname
      • cloneWithMarshaller

        public static <T> T cloneWithMarshaller​(Marshaller marshaller,
                                                T x)
        Clones parameter x of type T with a given Marshaller reference;
        Returns:
        a deep clone of an object parameter x
      • composeWithExceptions

        public static Runnable composeWithExceptions​(Runnable a,
                                                     Runnable b)
        Given two Runnables, return a Runnable that executes both in sequence, even if the first throws an exception, and if both throw exceptions, add any exceptions thrown by the second as suppressed exceptions of the first.
      • safeEquals

        public static boolean safeEquals​(Object a,
                                         Object b)
        Null-safe equality test.
        Parameters:
        a - first object to compare
        b - second object to compare
        Returns:
        true if the objects are equals or both null, false otherwise.
      • prettyPrintTime

        public static String prettyPrintTime​(long time,
                                             TimeUnit unit)
      • currentMillisFromNanotime

        public static long currentMillisFromNanotime()
        System.nanoTime() is less expensive than System.currentTimeMillis() and better suited to measure time intervals. It's NOT suited to know the current time, for example to be compared with the time of other nodes.
        Returns:
        the value of System.nanoTime(), but converted in Milliseconds.
      • prettyPrintTime

        public static String prettyPrintTime​(long millis)
        Prints a time for display
        Parameters:
        millis - time in millis
        Returns:
        the time, represented as millis, seconds, minutes or hours as appropriate, with suffix
      • readStream

        public static byte[] readStream​(InputStream is)
                                 throws IOException
        Reads the given InputStream fully, closes the stream and returns the result as a byte array.
        Parameters:
        is - the stream to read
        Returns:
        the read bytes
        Throws:
        IOException - in case of stream read errors
      • read

        public static String read​(InputStream is)
                           throws IOException
        Reads the given InputStream fully, closes the stream and returns the result as a String.
        Parameters:
        is - the stream to read
        Returns:
        the UTF-8 string
        Throws:
        IOException - in case of stream read errors
      • close

        public static void close​(Socket s)
      • close

        public static void close​(Context ctx)
      • flushAndCloseStream

        public static void flushAndCloseStream​(OutputStream o)
      • flushAndCloseOutput

        public static void flushAndCloseOutput​(ObjectOutput o)
      • printArray

        public static String printArray​(byte[] array)
      • printArray

        public static String printArray​(byte[] array,
                                        boolean withHash)
      • toHexString

        public static String toHexString​(byte[] input)
      • toHexString

        public static String toHexString​(byte[] input,
                                         int limit)
      • toHexString

        public static String toHexString​(byte[] input,
                                         int offset,
                                         int limit)
      • padString

        public static String padString​(String s,
                                       int minWidth)
      • threadDump

        public static String threadDump()
      • hexIdHashCode

        public static String hexIdHashCode​(Object o)
        Prints the identity hash code of the object passed as parameter in an hexadecimal format in order to safe space.
      • hexDump

        public static String hexDump​(byte[] buffer)
      • addHexByte

        public static void addHexByte​(StringBuilder buf,
                                      byte b)
      • constructDouble

        public static Double constructDouble​(Class<?> type,
                                             Object o)
      • getNormalizedHash

        public static int getNormalizedHash​(Object object,
                                            Hash hashFct)
        Applies the given hash function to the hash code of a given object, and then normalizes it to ensure a positive value is always returned.
        Parameters:
        object - to hash
        hashFct - hash function to apply
        Returns:
        a non-null, non-negative normalized hash code for a given object
      • getSegmentSize

        public static int getSegmentSize​(int numSegments)
        Returns the size of each segment, given a number of segments.
        Parameters:
        numSegments - number of segments required
        Returns:
        the size of each segment
      • isIBMJavaVendor

        public static boolean isIBMJavaVendor()
      • findNextHighestPowerOfTwo

        public static int findNextHighestPowerOfTwo​(int num)
        Returns a number such that the number is a power of two that is equal to, or greater than, the number passed in as an argument. The smallest number returned will be 1, not 0.
      • hashCode

        public static int hashCode​(byte[] bytes,
                                   int size)
        A function that calculates hash code of a byte array based on its contents but using the given size parameter as deliminator for the content.
      • prettyPrintSubject

        public static String prettyPrintSubject​(Subject subject)
        Prints Subject's principals as a one-liner (as opposed to default Subject's toString() method, which prints every principal on separate line).
      • arrayConcat

        @SafeVarargs
        public static <T> T[] arrayConcat​(T[] first,
                                          T[]... rest)
        Concatenates an arbitrary number of arrays returning a new array containing all elements
      • threadLocalRandomUUID

        public static UUID threadLocalRandomUUID()
        Uses a ThreadLocalRandom to generate a UUID. Faster, but not secure
      • unicodeEscapeString

        public static String unicodeEscapeString​(String s)
      • unicodeUnescapeString

        public static String unicodeUnescapeString​(String s)
      • getInstanceSupplier

        public static <T> Supplier<T> getInstanceSupplier​(Class<T> klass)
      • recursiveFileRemove

        public static void recursiveFileRemove​(String directoryName)
        Deletes directory recursively.
        Parameters:
        directoryName - Directory to be deleted
      • recursiveFileRemove

        public static void recursiveFileRemove​(File directory)
        Deletes directory recursively.
        Parameters:
        directory - Directory to be deleted
      • isBasicType

        public static boolean isBasicType​(Class<?> type)
      • toCharArray

        public static char[] toCharArray​(String s)
      • objectArray

        public static Object[] objectArray​(int length)
      • stringArray

        public static String[] stringArray​(int length)