Package com.storedobject.core

Class Utility

java.lang.Object

com.storedobject.core.Utility

public class Utility
extends Object

General utility methods.

Author:

Syam

Field Summary

Fields

Modifier and Type	Field	Description
static final Date	BLANK_DATE	Blank date: The local date Jan 1, 1800 is considered blank by the platform for internal purposes.
static final long	BLANK_TIME	Blank time: The local time Jan 1, 1800 0:00 is considered blank by the platform for internal purposes.

Constructor Summary

Constructors

Constructor	Description
Utility()

Method Summary

Modifier and Type	Method	Description
static <T> T	construct(Class<T> objectClass, Class<?>[] paramClasses, Object[] params)	Construct an instance of an object by creating a Constructor that matches best with the parameters passed.
static <T, O> O[]	copyTo(Iterable<T> iterable, O[] array, Function<T,O> converter)	Copies elements from an iterable to an array using a provided converter function.
static Method	getMethod(Class<?> ofClass, String methodName, Class<?> parameter)	Get a method of a class.
static <D extends Date> boolean	isEmpty(D dateTime)	Check whether the given date/time is empty/blank or not.
static boolean	isRightAligned(Object value)	Is the given value right-aligned?
static int	size(List<?> list, int startingIndex, int endingIndex)	Get the size of a sub-list.
static String	stackTrace()	Return the stack trace of the current thread at the current line as a string.
static String	stackTrace(Throwable error)	Return the stack trace of the given Throwable as a string.
static <O> Stream<O>	stream(Iterable<O> iterable)	Create a Stream from Iterable.
static <O> Stream<O>	stream(Iterator<O> iterator)	Create a Stream from Iterator.
static <T> Stream<T>	stream(List<T> list, int startingIndex, int endingIndex)	Get the stream of a sub-list.

Methods inherited from class java.lang.Object

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

Field Details

BLANK_TIME

public static final long BLANK_TIME

Blank time: The local time Jan 1, 1800 0:00 is considered blank by the platform for internal purposes.

See Also:

• Constant Field Values

BLANK_DATE

public static final Date BLANK_DATE

Blank date: The local date Jan 1, 1800 is considered blank by the platform for internal purposes.

Constructor Details

Utility

public Utility()

Method Details

size

public static int size(List<?> list,
 int startingIndex,
 int endingIndex)

Get the size of a sub-list. Index values will be re-adjusted to the valid range automatically to eliminate any exceptions.

Parameters:

list - List from which sub-list to be obtained.

startingIndex - Starting index.

endingIndex - Ending index.

Returns:

Size.

stream

public static <T> Stream<T> stream(List<T> list,
 int startingIndex,
 int endingIndex)

Get the stream of a sub-list. Index values will be re-adjusted to the valid range automatically to eliminate any exceptions.

Parameters:

list - List from which sub-list to be obtained.

startingIndex - Starting index.

endingIndex - Ending index.

Returns:

Stream.

isRightAligned

public static boolean isRightAligned(Object value)

Is the given value right-aligned? (Examples of right-aligned values are numeric values, quantity etc.) The notion of right-alignment depends on the locale. Here, the meaning is as per left-to-right language convention.

Note: A null value is considered as not right-aligned.

Parameters:

value - Value to check. This could be Class of the value too.

Returns:

True if right-aligned, otherwise false.

isEmpty

public static <D extends Date> boolean isEmpty(D dateTime)

Check whether the given date/time is empty/blank or not.

Type Parameters:

D - Type of date/timestamp.

Parameters:

dateTime - Date/timestamp to check.

Returns:

True if empty/blank, otherwise false.

stream

public static <O> Stream<O> stream(Iterable<O> iterable)

Create a Stream from Iterable.

Type Parameters:

O - Type of stream element.

Parameters:

iterable - Iterable from which stream needs to be created.

Returns:

Stream.

stream

public static <O> Stream<O> stream(Iterator<O> iterator)

Create a Stream from Iterator.

Type Parameters:

O - Type of stream element.

Parameters:

iterator - Iterator from which stream needs to be created.

Returns:

Stream.

construct

public static <T> T construct(Class<T> objectClass,
 Class<?>[] paramClasses,
 Object[] params)

Construct an instance of an object by creating a Constructor that matches best with the parameters passed.

Type Parameters:

T - The type of object to be created.

Parameters:

objectClass - The class of the object to be created.

paramClasses - List of classes of the parameters. (These could be subclasses of the classes of the actual parameter instances).

params - Actual parameter instances to be used.

Returns:

The new instance or null if an instance can not be created because no matching constructor is found.

Throws:

LogicRedirected - If the instance is a logic, and it is redirected when instantiated.

getMethod

public static Method getMethod(Class<?> ofClass,
 String methodName,
 Class<?> parameter)

Get a method of a class. If a method is not found, it will look for methods that take superclasses of the parameter.

Parameters:

ofClass - Of class.

methodName - Method name.

parameter - Method parameter type (Only single parameter is supported).

Returns:

Method if found, otherwise, null.

stackTrace

public static String stackTrace()

Return the stack trace of the current thread at the current line as a string. Useful for logging.

Returns:

Stack trace as a string.

stackTrace

public static String stackTrace(Throwable error)

Return the stack trace of the given Throwable as a string. Useful for logging.

Parameters:

error - Throwable instance.

Returns:

Stack trace as a string.

copyTo

public static <T,
O> O[] copyTo(Iterable<T> iterable,
 O[] array,
 Function<T,O> converter)

Copies elements from an iterable to an array using a provided converter function.

Type Parameters:

T - Type of elements in the iterable.

O - Type of elements in the array.

Parameters:

iterable - The iterable containing elements to be copied.

array - The array to copy elements into. Must be of type O[].

converter - The function that converts elements from type T to type O.

Returns:

The array with copied elements. Returns null if either the iterable or the array is null.