Package io.hekate.core.internal.util

Class Utils

java.lang.Object

io.hekate.core.internal.util.Utils

public final class Utils
extends Object

Common utilities.

Field Summary

Fields

Modifier and Type	Field	Description
static int	MAGIC_BYTES	Magic bytes that should be appended to the first packet of a network connection.
static String	NL	Shortcut for System.lineSeparator().
static Charset	UTF_8	Charset for UTF-8.

Method Summary

Modifier and Type	Method	Description
static String	byteSizeFormat(long bytes)
static String	camelCase(CharSequence str)
static boolean	isPowerOfTwo(int n)	Returns true if the specified value is a power of two.
static int	mod(int hash, int size)
static String	nullOrTrim(String str)	Returns null if the specified string is null or is an empty string after trimming; returns a trimmed string otherwise.
static String	nullOrTrim(String str, String defaultVal)	Returns defaultVal if the specified string is null or is an empty string after trimming; returns a trimmed string otherwise.
static <T> List<T>	nullSafeImmutableCopy(List<T> source)	Returns an immutable copy of the specified list by filtering out all null elements.
static String	numberFormat(String pattern, Number number)
static <T> String	toString(Collection<T> collection, Function<? super T,String> mapper)	Converts the specified collection to a comma-separated string by applying the specified mapper to each element and wrapping the resulting string with {...}.

Methods inherited from class java.lang.Object

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

Field Detail

NL

public static final String NL

Shortcut for System.lineSeparator().

UTF_8

public static final Charset UTF_8

Charset for UTF-8.

MAGIC_BYTES

public static final int MAGIC_BYTES

Magic bytes that should be appended to the first packet of a network connection.

See Also:

Constant Field Values

Method Detail

numberFormat

public static String numberFormat(String pattern,
                                  Number number)

byteSizeFormat

public static String byteSizeFormat(long bytes)

mod

public static int mod(int hash,
                      int size)

isPowerOfTwo

public static boolean isPowerOfTwo(int n)

Returns true if the specified value is a power of two.

Parameters:

n - Number to check.

Returns:

true if the specified value is a power of two.

toString

public static <T> String toString(Collection<T> collection,
                                  Function<? super T,String> mapper)

Converts the specified collection to a comma-separated string by applying the specified mapper to each element and wrapping the resulting string with {...}.

Type Parameters:

T - Collection type.

Parameters:

collection - Collection.

mapper - Element mapper.

Returns:

String that has the following format: {element1, element2, ..., elementN}

nullOrTrim

public static String nullOrTrim(String str)

Returns null if the specified string is null or is an empty string after trimming; returns a trimmed string otherwise.

Parameters:

str - String.

Returns:

null or trimmed string.

nullOrTrim

public static String nullOrTrim(String str,
                                String defaultVal)

Returns defaultVal if the specified string is null or is an empty string after trimming; returns a trimmed string otherwise.

Parameters:

str - String.

defaultVal - Default value.

Returns:

null or trimmed string.

camelCase

public static String camelCase(CharSequence str)

nullSafeImmutableCopy

public static <T> List<T> nullSafeImmutableCopy(List<T> source)

Returns an immutable copy of the specified list by filtering out all null elements.

Type Parameters:

T - Element type.

Parameters:

source - Source list, can be null (in such case an empty list will be returned by this method).

Returns:

Immutable copy of the specified list.