org.infinispan.commons.util

Class Util

java.lang.Object

org.infinispan.commons.util.Util

public final class Util
extends Object

General utility methods used throughout the Infinispan code base.

Since:

4.0

Author:

Brian Stansberry, Galder Zamarreño

Field Summary

Fields

Modifier and Type	Field and Description
static byte[]	EMPTY_BYTE_ARRAY
static Object[]	EMPTY_OBJECT_ARRAY
static String[]	EMPTY_STRING_ARRAY

Method Summary

Modifier and Type	Method and Description
static void	addHexByte(StringBuilder buf, byte b)
static <T> T[]	arrayConcat(T[] first, T[]... rest) Concatenates an arbitrary number of arrays returning a new array containing all elements
static <T> Set<T>	asSet(T... a)
static <T> T	cloneWithMarshaller(Marshaller marshaller, T x) Clones parameter x of type T with a given Marshaller reference;
static void	close(AutoCloseable... cls)
static void	close(AutoCloseable cl)
static void	close(Context ctx)
static void	close(Socket s)
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.
static Double	constructDouble(Class<?> type, Object o)
static long	currentMillisFromNanotime() System.nanoTime() is less expensive than System.currentTimeMillis() and better suited to measure time intervals.
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.
static void	flushAndCloseOutput(ObjectOutput o)
static void	flushAndCloseStream(OutputStream o)
static String	formatString(Object message, Object... params)
static ClassLoader[]	getClassLoaders(ClassLoader appClassLoader)
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.
static <T> T	getInstance(String classname, ClassLoader cl) Instantiates a class based on the class name provided.
static <T> T	getInstanceStrict(Class<T> clazz) Similar to getInstance(Class) except that exceptions are propagated to the caller.
static <T> T	getInstanceStrict(String classname, ClassLoader cl) Similar to getInstance(String, ClassLoader) except that exceptions are propagated to the caller.
static <T> Supplier<T>	getInstanceSupplier(Class<T> klass)
static <T> Supplier<T>	getInstanceSupplier(String className, ClassLoader classLoader)
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.
static InputStream	getResourceAsStream(String resourcePath, ClassLoader userClassLoader)
static String	getResourceAsString(String resourcePath, ClassLoader userClassLoader)
static int	getSegmentSize(int numSegments) Returns the size of each segment, given a number of segments.
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.
static String	hexDump(byte[] buffer)
static String	hexDump(ByteBuffer buffer)
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.
static boolean	isBasicType(Class<?> type)
static boolean	isIBMJavaVendor()
static boolean	isOSGiContext() Tries to determine if the code is running in an OSGi context.
static String	join(List<String> strings, String separator)
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.
static <T> Class<T>	loadClassStrict(String classname, ClassLoader userClassLoader) Loads the specified class using the passed classloader, or, if it is null the Infinispan classes' classloader.
static Object[]	objectArray(int length)
static String	padString(String s, int minWidth)
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).
static String	prettyPrintTime(long millis) Prints a time for display
static String	prettyPrintTime(long time, TimeUnit unit)
static String	printArray(byte[] array)
static String	printArray(byte[] array, boolean withHash)
static String	read(InputStream is) Reads the given InputStream fully, closes the stream and returns the result as a String.
static byte[]	readStream(InputStream is) Reads the given InputStream fully, closes the stream and returns the result as a byte array.
static void	recursiveFileRemove(File directory) Deletes directory recursively.
static void	recursiveFileRemove(String directoryName) Deletes directory recursively.
static void	renameTempFile(File tempFile, File lockFile, File dstFile, BiConsumer<File,File> renameFailed)
static CacheException	rewrapAsCacheException(Throwable t)
static boolean	safeEquals(Object a, Object b) Null-safe equality test.
static String[]	stringArray(int length)
static String	threadDump()
static UUID	threadLocalRandomUUID() Uses a ThreadLocalRandom to generate a UUID.
static char[]	toCharArray(String s)
static String	toHexString(byte[] input)
static String	toHexString(byte[] input, int limit)
static String	toHexString(byte[] input, int offset, int limit)
static <E> String	toStr(Collection<E> collection)
static String	toStr(Object o)
static String	unicodeEscapeString(String s)
static String	unicodeUnescapeString(String s)
static String	xmlify(String s)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

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

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

getClassLoaders

public static ClassLoader[] getClassLoaders(ClassLoader appClassLoader)

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

getResourceAsStream

public static InputStream getResourceAsStream(String resourcePath,
                                              ClassLoader userClassLoader)

getResourceAsString

public static String getResourceAsString(String resourcePath,
                                         ClassLoader userClassLoader)
                                  throws IOException

Throws:

IOException

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

getInstanceStrict

public static <T> T getInstanceStrict(Class<T> clazz)
                               throws IllegalAccessException,
                                      InstantiationException

Similar to getInstance(Class) except that exceptions are propagated to the caller.

Parameters:

clazz - class to instantiate

Returns:

an instance of the class

Throws:

IllegalAccessException

InstantiationException

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

getInstanceStrict

public static <T> T getInstanceStrict(String classname,
                                      ClassLoader cl)
                               throws ClassNotFoundException,
                                      InstantiationException,
                                      IllegalAccessException

Similar to getInstance(String, ClassLoader) except that exceptions are propagated to the caller.

Parameters:

classname - class to instantiate

Returns:

an instance of classname

Throws:

ClassNotFoundException

InstantiationException

IllegalAccessException

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(AutoCloseable cl)

close

public static void close(Socket s)

close

public static void close(AutoCloseable... cls)

close

public static void close(Context ctx)

flushAndCloseStream

public static void flushAndCloseStream(OutputStream o)

flushAndCloseOutput

public static void flushAndCloseOutput(ObjectOutput o)

formatString

public static String formatString(Object message,
                                  Object... params)

toStr

public static String toStr(Object o)

toStr

public static <E> String toStr(Collection<E> collection)

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()

rewrapAsCacheException

public static CacheException rewrapAsCacheException(Throwable t)

asSet

@SafeVarargs
public static <T> Set<T> asSet(T... a)

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)

hexDump

public static String hexDump(ByteBuffer 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()

join

public static String join(List<String> strings,
                          String separator)

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)

getInstanceSupplier

public static <T> Supplier<T> getInstanceSupplier(String className,
                                                  ClassLoader classLoader)

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)

xmlify

public static String xmlify(String s)

toCharArray

public static char[] toCharArray(String s)

objectArray

public static Object[] objectArray(int length)

stringArray

public static String[] stringArray(int length)

renameTempFile

public static void renameTempFile(File tempFile,
                                  File lockFile,
                                  File dstFile,
                                  BiConsumer<File,File> renameFailed)
                           throws IOException

Throws:

IOException