fr.cnes.doi.utils

Class Utils

java.lang.Object

fr.cnes.doi.utils.Utils

public final class Utils
extends Object

Utility Class.

Author:

Jean-Christophe Malapert, Claire

Field Summary

Fields

Modifier and Type	Field and Description
static String	APP_LOGGER_NAME Name of the logger to measure performances "fr.cnes.doi.logging.app".
static Object[]	EMPTY_OBJECT_ARRAY An empty immutable Object array.
static String	HTTP_LOGGER_NAME Name of the logger for http requests and answers "fr.cnes.doi.logging.api".
static String	SECURITY_LOGGER_NAME Name of the logger to measure performances "fr.cnes.doi.logging.security".
static String	SHELL_LOGGER_NAME Name of the logger in console without date.

Constructor Summary

Constructors

Modifier	Constructor and Description
private	Utils() "Static" class cannot be instantiated

Method Summary

Modifier and Type	Method and Description
static <T,E> Set<T>	getKeysByValue(Map<T,E> map, E value) Returns the keys related to a value within a map.
static int	getLength(Object array) Returns the length of the specified array.
static boolean	isEmpty(CharSequence charSeq) Checks whether the char sequence is empty.
static boolean	isEmpty(Object[] array) Checks if an array of Objects is empty or null.
static boolean	isNotEmpty(CharSequence charSeq) Checks whether the char sequence is not empty.
static Object[]	nullToEmpty(Object[] array) Defensive programming technique to change a null reference to an empty one.
static <T> T[]	nullToEmpty(T[] array, Class<T[]> type) Defensive programming technique to change a null reference to an empty one.
static String	transformPasswordToStars(String password) Transform password to stars

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

An empty immutable Object array.

SHELL_LOGGER_NAME

public static final String SHELL_LOGGER_NAME

Name of the logger in console without date.

See Also:

Constant Field Values

HTTP_LOGGER_NAME

public static final String HTTP_LOGGER_NAME

Name of the logger for http requests and answers "fr.cnes.doi.logging.api".

See Also:

Constant Field Values

APP_LOGGER_NAME

public static final String APP_LOGGER_NAME

Name of the logger to measure performances "fr.cnes.doi.logging.app".

See Also:

Constant Field Values

SECURITY_LOGGER_NAME

public static final String SECURITY_LOGGER_NAME

Name of the logger to measure performances "fr.cnes.doi.logging.security".

See Also:

Constant Field Values

Constructor Detail

Utils

private Utils()

"Static" class cannot be instantiated

Method Detail

isEmpty

public static boolean isEmpty(CharSequence charSeq)

Checks whether the char sequence is empty.

Parameters:

charSeq - the char sequence

Returns:

True when the char sequence is empty otherwise False

isNotEmpty

public static boolean isNotEmpty(CharSequence charSeq)

Checks whether the char sequence is not empty.

Parameters:

charSeq - the char sequence

Returns:

True when the char sequence is not empty otherwise False

getKeysByValue

public static <T,E> Set<T> getKeysByValue(Map<T,E> map,
                                          E value)

Returns the keys related to a value within a map.

Type Parameters:

T - the type of the key

E - the type of the value

Parameters:

map - map

value - value to search

Returns:

the keys related to a value

nullToEmpty

public static <T> T[] nullToEmpty(T[] array,
                                  Class<T[]> type)
                           throws IllegalArgumentException

Defensive programming technique to change a null reference to an empty one.

This method returns an empty array for a null input array.

Type Parameters:

T - the class type

Parameters:

array - the array to check for null or empty

type - the class representation of the desired array

Returns:

the same array, public static empty array if null

Throws:

IllegalArgumentException - if the type argument is null

nullToEmpty

public static Object[] nullToEmpty(Object[] array)

Defensive programming technique to change a null reference to an empty one.

This method returns an empty array for a null input array.

As a memory optimizing technique an empty array passed in will be overridden with the empty public static references in this class.

Parameters:

array - the array to check for null or empty

Returns:

the same array, public static empty array if null or empty input

isEmpty

public static boolean isEmpty(Object[] array)

Checks if an array of Objects is empty or null.

Parameters:

array - the array to test

Returns:

true if the array is empty or null

getLength

public static int getLength(Object array)
                     throws IllegalArgumentException

Returns the length of the specified array. This method can deal with Object arrays and with primitive arrays.

If the input array is null, 0 is returned.

 Utils.getLength(null)            = 0
 Utils.getLength([])              = 0
 Utils.getLength([null])          = 1
 Utils.getLength([true, false])   = 2
 Utils.getLength([1, 2, 3])       = 3
 Utils.getLength(["a", "b", "c"]) = 3
 

Parameters:

array - the array to retrieve the length from, may be null

Returns:

The length of the array, or 0 if the array is null

Throws:

IllegalArgumentException - if the object argument is not an array.

transformPasswordToStars

public static String transformPasswordToStars(String password)

Transform password to stars

Parameters:

password - password to transform

Returns:

stars