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

      • HEX_DUMP_LIMIT

        public static final int HEX_DUMP_LIMIT
      • EMPTY_OBJECT_ARRAY

        public static final Object[] EMPTY_OBJECT_ARRAY
      • EMPTY_STRING_ARRAY

        public static final String[] EMPTY_STRING_ARRAY
      • EMPTY_THROWABLE_ARRAY

        public static final Throwable[] EMPTY_THROWABLE_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
      • 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
      • newInstanceOrNull

        public static <T> T newInstanceOrNull​(Class<T> clazz,
                                              Class[] parameterTypes,
                                              Object... arguments)
        Instantiates a class by invoking the constructor that matches the provided parameter types passing the given arguments. If no matching constructor is found this will return null. Note that the constructor must be public.

        Any exceptions encountered are wrapped in a CacheConfigurationException and rethrown.

        Type Parameters:
        T - the instance type
        Parameters:
        clazz - class to instantiate
        Returns:
        the new instance if a matching constructor was found otherwise null
      • 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
      • 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
      • 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)
      • 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[] data)
      • hexDump

        public static String hexDump​(byte[] buffer,
                                     int offset,
                                     int actualLength)
      • addHexByte

        public static void addHexByte​(StringBuilder buf,
                                      byte b)
      • 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
      • 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. Due to having to be a power of two, the highest int this can return is 231 since int is signed.
      • 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).
      • 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)
      • recursiveFileRemove

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

        public static void recursiveFileRemove​(Path path)
      • recursiveFileRemove

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

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

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

        public static String[] stringArray​(int length)
      • throwableArray

        public static Throwable[] throwableArray​(int length)
      • requireNonNullElse

        public static <T> T requireNonNullElse​(T obj,
                                               T defaultObj)
      • longToBytes

        public static void longToBytes​(long val,
                                       byte[] array,
                                       int offset)
      • unwrapExceptionMessage

        public static String unwrapExceptionMessage​(Throwable t)
      • arraysEqual

        public static boolean arraysEqual​(byte[] a,
                                          int aFromIndex,
                                          int aToIndex,
                                          byte[] b,
                                          int bFromIndex,
                                          int bToIndex)
        This method is to be replaced by Java 9 Arrays#equals with the same arguments.
        Parameters:
        a - first array to test contents
        aFromIndex - the offset into the first array to start comparison
        aToIndex - the last element (exclusive) of the first array to compare
        b - second array to test contents
        bFromIndex - the offset into the second array to start comparison
        bToIndex - the last element (exclusive) of the second array to compare
        Returns:
        if the bytes in the two array ranges are equal