Class ObjectUtils

java.lang.Object

io.fluxzero.common.ObjectUtils

public class ObjectUtils
extends Object

Utility class for common object handling, memoization, concurrency, stream processing, and error handling.

Offers reusable tools for:

• Memoizing functional interfaces
• Retry-safe functional wrappers (callables, consumers, etc.)
• Stream deduplication and flattening
• Property file manipulation
• Exception-safe task execution and error unwrapping
• Custom thread factories and naming

Constructor Summary

Constructors

Constructor	Description
ObjectUtils()

Method Summary

Modifier and Type	Method	Description
static Callable<?>	asCallable(ThrowingRunnable runnable)	Converts a ThrowingRunnable into a Callable<Object> that returns null.
static Callable<?>	asCallable(Runnable runnable)	Converts a standard Runnable into a Callable<Object> that returns null.
static <T> Consumer<T>	asConsumer(ThrowingConsumer<T> consumer)
static <T,R> Function<T,R>	asFunction(ThrowingFunction<T,R> function)
static Properties	asProperties(String content)	Parses Java Properties from a string.
static Runnable	asRunnable(ThrowingRunnable runnable)
static Runnable	asRunnable(Callable<?> callable)
static Stream<?>	asStream(Object value)	Converts an object into a stream.
static <T> Supplier<T>	asSupplier(Callable<T> callable)
static <T> T	call(Callable<T> callable)	Calls the given callable, forcibly rethrowing exceptions.
static String	capitalize(String value)	Capitalizes the first character of a string, leaving null and empty strings unchanged.
static <T> Stream<T>	concat(Stream<? extends T>... streams)	Concatenates multiple streams into a single flat stream.
static Properties	copyOf(Properties properties)	Creates a deep copy of a Properties instance.
static Executor	cpuExecutor()	Returns the classloader-wide executor for bounded chunks of CPU work, isolated from the JVM common pool.
static int	cpuParallelism()	Returns the target CPU parallelism, including the work formerly performed by a parallel stream's caller.
static <T> List<T>	deduplicate(List<T> list)	Deduplicates elements in the list, preserving the last occurrence.
static <T> List<T>	deduplicate(List<T> list, Function<T,?> idFunction)	Deduplicates elements using a key extractor, preserving the last occurrence.
static <T> List<T>	deduplicate(List<T> list, Function<T,?> idFunction, boolean keepFirst)	Deduplicates elements using a key extractor, optionally keeping the first occurrence.
static <T> Predicate<T>	distinctByKey(Function<? super T, ?> keyExtractor)	Returns a predicate that filters out duplicates based on a key extractor.
static Object	forceThrow(Throwable error)	Forces the given throwable to be thrown.
static byte[]	getBytes(ByteBuffer buffer)	Extracts the byte array from a ByteBuffer.
static Consumer<Runnable>	ifTrue(boolean check)	Returns a consumer that runs the task only if check is true.
static <T> T	inParallel(Supplier<T> operation)	Evaluates a parallel stream terminal operation on the isolated CPU pool and awaits its result.
static boolean	isBlank(CharSequence value)	Returns whether a character sequence is null, empty, or contains only whitespace.
static boolean	isNumeric(CharSequence value)	Returns whether a character sequence is non-empty and consists entirely of Unicode digits.
static <T> Stream<T>	iterate(T seed, UnaryOperator<T> f, Predicate<T> breakCondition)	Creates a stream that stops once the break condition evaluates true.
static byte[]	join(byte[]... chunks)	Combines multiple byte arrays into a single byte array by concatenating their contents in the given order.
static <T> List<T>	limitByCumulativeWeight(List<T> list, long maxWeight, ToLongFunction<T> weightFunction)	Returns a prefix of the list whose cumulative weight stays within maxWeight.
static <T,U,R> MemoizingBiFunction<T,U,R>	memoize(BiFunction<T,U,R> supplier)
static <K,V> MemoizingFunction<K,V>	memoize(Function<K,V> supplier)
static <T> MemoizingSupplier<T>	memoize(Supplier<T> supplier)
static Properties	merge(Properties a, Properties b)	Merges two Properties instances into a new one.
static ThreadFactory	newPlatformThreadFactory(String prefix)	Creates a new ThreadFactory with a named prefix.
static ThreadFactory	newVirtualThreadFactory(String prefix)	Creates a new named virtual-thread ThreadFactory.
static Executor	newWorkerExecutor(String prefix)	Creates a named virtual-thread-per-task executor without a queue or persistent worker resources.
static ExecutorService	newWorkerPool(String prefix, int poolSize)	Creates an executor with one named virtual thread per task.
static ThreadFactory	newWorkerThreadFactory(String prefix)	Creates a named virtual-thread factory for workers.
static <T,U> BiPredicate<T,U>	noOpBiPredicate()	Returns a bi-predicate that always evaluates to true.
static <T> Predicate<T>	noOpPredicate()	Returns a predicate that always evaluates to true.
static RuntimeException	rethrow(Throwable e)	Unwraps then returns the given Throwable as an unchecked exception.
static void	run(ThrowingRunnable runnable)	Executes the runnable, forcibly rethrowing exceptions as unchecked.
static void	runInParallel(Runnable operation)	Runs a parallel terminal operation with the same isolation and completion contract as inParallel(Supplier).
static <T> Predicate<T>	silentTest(Predicate<T> predicate)	Returns a predicate that silently returns false when the given predicate throws an error.
static String	stackTrace(Throwable throwable)	Renders a throwable and its causes to the same text produced by Throwable.printStackTrace().
static String	stripAccents(String value)	Removes accents from a string while retaining otherwise compatible Unicode characters.
static boolean	supportsVirtualThreadWorkers()	Deprecated. SDK v2 requires Java 25 or newer, so callers no longer need a runtime-version check.
static <T> Consumer<? super T>	tryAccept(Consumer<? super T> consumer)	Returns a consumer that logs errors instead of propagating them.
static Runnable	tryCatch(Runnable runnable)	Wraps a runnable in a try/catch block that logs any exception on execution.
static void	tryRun(Runnable task)	Executes the runnable and logs any thrown exception.
static Throwable	unwrapException(Throwable e)	Recursively unwraps the cause of common wrapping exceptions.

Methods inherited from class Object

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

Constructor Details

ObjectUtils

public ObjectUtils()

Method Details

isBlank

public static boolean isBlank(CharSequence value)

Returns whether a character sequence is null, empty, or contains only whitespace.

isNumeric

public static boolean isNumeric(CharSequence value)

Returns whether a character sequence is non-empty and consists entirely of Unicode digits.

capitalize

public static String capitalize(String value)

Capitalizes the first character of a string, leaving null and empty strings unchanged.

stripAccents

public static String stripAccents(String value)

Removes accents from a string while retaining otherwise compatible Unicode characters.

stackTrace

public static String stackTrace(Throwable throwable)

Renders a throwable and its causes to the same text produced by Throwable.printStackTrace().

noOpPredicate

public static <T> Predicate<T> noOpPredicate()

Returns a predicate that always evaluates to true.

noOpBiPredicate

public static <T,U> BiPredicate<T,U> noOpBiPredicate()

Returns a bi-predicate that always evaluates to true.

distinctByKey

public static <T> Predicate<T> distinctByKey(Function<? super T, ?> keyExtractor)

Returns a predicate that filters out duplicates based on a key extractor.

iterate

public static <T> Stream<T> iterate(T seed,
 UnaryOperator<T> f,
 Predicate<T> breakCondition)

Creates a stream that stops once the break condition evaluates true.

concat

@SafeVarargs
public static <T> Stream<T> concat(Stream<? extends T>... streams)

Concatenates multiple streams into a single flat stream.

deduplicate

public static <T> List<T> deduplicate(List<T> list)

Deduplicates elements in the list, preserving the last occurrence.

deduplicate

public static <T> List<T> deduplicate(List<T> list,
 Function<T,?> idFunction)

Deduplicates elements using a key extractor, preserving the last occurrence.

deduplicate

public static <T> List<T> deduplicate(List<T> list,
 Function<T,?> idFunction,
 boolean keepFirst)

Deduplicates elements using a key extractor, optionally keeping the first occurrence.

limitByCumulativeWeight

public static <T> List<T> limitByCumulativeWeight(List<T> list,
 long maxWeight,
 ToLongFunction<T> weightFunction)

Returns a prefix of the list whose cumulative weight stays within maxWeight.

If the first item already exceeds maxWeight, it is still included so callers can make progress. A maxWeight of 0 or lower leaves the list unchanged.

asStream

public static Stream<?> asStream(Object value)

Converts an object into a stream. Supports Collection, Stream, Optional, or single value.

ifTrue

public static Consumer<Runnable> ifTrue(boolean check)

Returns a consumer that runs the task only if check is true.

forceThrow

public static Object forceThrow(Throwable error)

Forces the given throwable to be thrown.

call

public static <T> T call(Callable<T> callable)

Calls the given callable, forcibly rethrowing exceptions.

run

public static void run(ThrowingRunnable runnable)

Executes the runnable, forcibly rethrowing exceptions as unchecked.

asCallable

public static Callable<?> asCallable(ThrowingRunnable runnable)

Converts a ThrowingRunnable into a Callable<Object> that returns null.

asCallable

public static Callable<?> asCallable(Runnable runnable)

Converts a standard Runnable into a Callable<Object> that returns null.

tryRun

public static void tryRun(Runnable task)

Executes the runnable and logs any thrown exception.

tryCatch

public static Runnable tryCatch(Runnable runnable)

Wraps a runnable in a try/catch block that logs any exception on execution.

asSupplier

public static <T> Supplier<T> asSupplier(Callable<T> callable)

asRunnable

public static Runnable asRunnable(ThrowingRunnable runnable)

asFunction

public static <T,R> Function<T,R> asFunction(ThrowingFunction<T,R> function)

asConsumer

public static <T> Consumer<T> asConsumer(ThrowingConsumer<T> consumer)

asRunnable

public static Runnable asRunnable(Callable<?> callable)

getBytes

public static byte[] getBytes(ByteBuffer buffer)

Extracts the byte array from a ByteBuffer.

unwrapException

public static Throwable unwrapException(Throwable e)

Recursively unwraps the cause of common wrapping exceptions.

rethrow

public static RuntimeException rethrow(Throwable e)

Unwraps then returns the given Throwable as an unchecked exception. If the provided throwable is a RuntimeException or Error, it is returned as-is. Otherwise, it is wrapped in a new RuntimeException.

See Also:

• unwrapException(Throwable)

asProperties

public static Properties asProperties(String content)

Parses Java Properties from a string.

copyOf

public static Properties copyOf(Properties properties)

Creates a deep copy of a Properties instance.

merge

public static Properties merge(Properties a,
 Properties b)

Merges two Properties instances into a new one.

memoize

public static <T> MemoizingSupplier<T> memoize(Supplier<T> supplier)

memoize

public static <K,V> MemoizingFunction<K,V> memoize(Function<K,V> supplier)

memoize

public static <T,U,R> MemoizingBiFunction<T,U,R> memoize(BiFunction<T,U,R> supplier)

newPlatformThreadFactory

public static ThreadFactory newPlatformThreadFactory(String prefix)

Creates a new ThreadFactory with a named prefix.

newVirtualThreadFactory

public static ThreadFactory newVirtualThreadFactory(String prefix)

Creates a new named virtual-thread ThreadFactory.

newWorkerThreadFactory

public static ThreadFactory newWorkerThreadFactory(String prefix)

Creates a named virtual-thread factory for workers.

newWorkerPool

public static ExecutorService newWorkerPool(String prefix,
 int poolSize)

Creates an executor with one named virtual thread per task. The caller owns its shutdown. Concurrency and admission limits must be enforced by the submitting component, not by this executor.

Parameters:

prefix - the worker thread name prefix

poolSize - a positive legacy sizing hint; does not bound virtual-thread concurrency

newWorkerExecutor

public static Executor newWorkerExecutor(String prefix)

Creates a named virtual-thread-per-task executor without a queue or persistent worker resources. Inheritable thread locals are not copied; callers must propagate their intended context explicitly. The submitting component owns admission, task completion and cancellation. There is no executor shutdown phase, so late continuations of already accepted operations can still run during component shutdown.

Parameters:

prefix - worker thread name prefix

Returns:

an executor for independently completable, potentially blocking tasks

cpuExecutor

public static Executor cpuExecutor()

Returns the classloader-wide executor for bounded chunks of CPU work, isolated from the JVM common pool. Workers are daemon threads and may clear thread locals between submissions. Callers own batching and context propagation; blocking I/O belongs on a worker executor instead. This shared executor must not be shut down by individual components. Nested parallel work must use inParallel(Supplier).

cpuParallelism

public static int cpuParallelism()

Returns the target CPU parallelism, including the work formerly performed by a parallel stream's caller.

runInParallel

public static void runInParallel(Runnable operation)

Runs a parallel terminal operation with the same isolation and completion contract as inParallel(Supplier).

inParallel

public static <T> T inParallel(Supplier<T> operation)

Evaluates a parallel stream terminal operation on the isolated CPU pool and awaits its result. Nested calls already on that pool run directly. A caller's unrelated fork/join pool is never reused. The operation must complete its parallel work before returning; returning a lazy stream does not isolate it. Context must be propagated explicitly to the operation and its parallel tasks.

Type Parameters:

T - result type

Parameters:

operation - terminal operation

Returns:

the operation's result

supportsVirtualThreadWorkers

@Deprecated
public static boolean supportsVirtualThreadWorkers()

Deprecated.

SDK v2 requires Java 25 or newer, so callers no longer need a runtime-version check.

Returns true: virtual workers are available on every supported Java runtime.

tryAccept

public static <T> Consumer<? super T> tryAccept(Consumer<? super T> consumer)

Returns a consumer that logs errors instead of propagating them.

silentTest

public static <T> Predicate<T> silentTest(Predicate<T> predicate)

Returns a predicate that silently returns false when the given predicate throws an error.

join

public static byte[] join(byte[]... chunks)

Combines multiple byte arrays into a single byte array by concatenating their contents in the given order.