org.nuiton.util
Class ObjectUtil

java.lang.Object
  org.nuiton.util.ObjectUtil

public class ObjectUtil
extends Object

Outils pour manipuler des objets. Création d'un objet à partir d'une chaîne le décrivant, conversion d'un objet en Object, récupération de méthodes à partir de leur nom, de constructeurs à partir de leurs paramètres...

Created: 4 novembre 2004

Author:

bpoussin $Id: ObjectUtil.java 2360 2012-06-11 10:24:36Z tchemit $

Field Summary

protected static Integer	ZERO
protected static Byte	ZEROB
protected static Character	ZEROC
protected static Double	ZEROD
protected static Float	ZEROF
protected static Long	ZEROL

Method Summary

static Object	call(Object o, Method m, String... params) Call method m with params as String.
protected static Object	choiceArgument(Class<?> clazz, List args, boolean nullIfMissing) Permet de matcher un type d'argument attendu clazz parmi un ensemble possible de candidat.
static <E extends Cloneable> E	clone(E e) Clone object by introspection because Cloneable interface don't permit to call clone :(.
protected static Object	convert(String v, Class<?> clazz)
static Object	create(String classnameAndProperties) Create new object from string like org.nuiton.Toto(name=machine, int=10) where machine and int is properties on org.nuiton.Toto object.
static <E> E	deepClone(E e) Use serialization/deserialization to do deep clone of object
static <T> List<Constructor<T>>	getConstructor(Class<T> clazz, int paramNumber) Get all constructors that support paramNumber as parameters numbers.
static List<Method>	getMethod(Class<?> clazz, String methodName, boolean ignoreCase) Get all methods with name given in argument without check parameters.
static Object	getNullValue(Class<?> type) Obtains the null value for the given type (works too with primitive types).
static Class<?>	getPrimitiveClass(Class<?> clazz) Retourne la classe du type primitf associé avec la classe de de l'objet passé en parametre.
static boolean	isNullValue(boolean value)
static boolean	isNullValue(byte value)
static boolean	isNullValue(char value)
static boolean	isNullValue(double value)
static boolean	isNullValue(float value)
static boolean	isNullValue(int value)
static boolean	isNullValue(Object value) Tests if the given value is null according to default value for primitive types if nedded.
static boolean	isPrimitive(Class<?> clazz) Verifie si la classe est de type primitif.
static <E> E	newInstance(Class<E> clazz, Collection<?> args, boolean nullIfMissing) Invoke constructor on clazz to create new instance.
static <T> T	newInstance(Class<T> clazz, String... params) Create new instance of clazz, call constructor with params as String.
static Object	newInstance(String constructorWithParams)
static Object	toObject(boolean b) Method toObject transform a boolean to a Boolean object
static Object	toObject(byte b) Method toObject transform a byte to a Byte Object
static Object	toObject(char c) Method toObject transform a char to a Character Object
static Object	toObject(double d) Method toObject transform a double to a Double object
static Object	toObject(float f) Method toObject transform a float to a Float Object
static Object	toObject(int i) Method toObject transform an int to an Integer object
static Object	toObject(long l) Method toObject transform a long to a Long object
static Object	toObject(Object o) Method toObject
static Object	toObject(short s) Method toObject transform a short to a Short object

Methods inherited from class java.lang.Object

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

Field Detail

ZERO

protected static final Integer ZERO

ZEROC

protected static final Character ZEROC

ZEROF

protected static final Float ZEROF

ZEROL

protected static final Long ZEROL

ZEROD

protected static final Double ZEROD

ZEROB

protected static final Byte ZEROB

Method Detail

newInstance

public static <E> E newInstance(Class<E> clazz,
                                Collection<?> args,
                                boolean nullIfMissing)

Invoke constructor on clazz to create new instance. Try to find argument for constructor in args parameter.

Parameters:

clazz - class of object to instanciate

args - all possible parameter that constructor can used

nullIfMissing - if no suitable class or object found in args, use null value (no exception)

Returns:

new instance

Throws:

IllegalArgumentException - if something is wrong during instanciation

choiceArgument

protected static Object choiceArgument(Class<?> clazz,
                                       List args,
                                       boolean nullIfMissing)

Permet de matcher un type d'argument attendu clazz parmi un ensemble possible de candidat. Les candidats peuvent etre des classes qu'il faudra instancier pour satisfaire le type demande.

Parameters:

clazz - le type recherché

args - la liste des arguments ou des types

nullIfMissing - pour retourner nulle si l'argument n'est pas trouvé

Returns:

le type d'argument trouvé

create

public static Object create(String classnameAndProperties)
                     throws ClassNotFoundException,
                            InstantiationException,
                            IllegalAccessException,
                            InvocationTargetException,
                            NoSuchMethodException

Create new object from string like org.nuiton.Toto(name=machine, int=10) where machine and int is properties on org.nuiton.Toto object. Conversion between 10 in string and 10 as integer as automaticaly done

For String property you can use ex:

name="my string with , in string"

name='my string with , in string'

Parameters:

classnameAndProperties -

Returns:

the instanciated object

Throws:

ClassNotFoundException

IllegalAccessException

InstantiationException

NoSuchMethodException

InvocationTargetException

convert

protected static Object convert(String v,
                                Class<?> clazz)

clone

public static <E extends Cloneable> E clone(E e)
                                 throws CloneNotSupportedException

Clone object by introspection because Cloneable interface don't permit to call clone :(. This methode replace next code that don't work :(

 if (o instanceof Cloneable) {
   Object n = ((Cloneable)o).clone();
 }
 

Parameters:

e - object to clone

Returns:

new instance of E

Throws:

CloneNotSupportedException - if some error occur during clone

deepClone

public static <E> E deepClone(E e)
                   throws CloneNotSupportedException

Use serialization/deserialization to do deep clone of object

Parameters:

e - object to clone

Returns:

new instance of E

Throws:

CloneNotSupportedException - if some error occur during clone

call

public static Object call(Object o,
                          Method m,
                          String... params)
                   throws IllegalAccessException,
                          IllegalArgumentException,
                          InvocationTargetException,
                          InstantiationException

Call method m with params as String. Each param is converted to required type for method with beanutils converter

Parameters:

o - object where method must be call

m - method to call

params - parameters for method call

Returns:

returned method's value

Throws:

IllegalAccessException

IllegalArgumentException

InvocationTargetException

InstantiationException

getMethod

public static List<Method> getMethod(Class<?> clazz,
                                     String methodName,
                                     boolean ignoreCase)

Get all methods with name given in argument without check parameters.

Parameters:

clazz - where to search method

methodName - method name to search

ignoreCase - if true, ignore difference in method name case

Returns:

list of detected methods

newInstance

public static Object newInstance(String constructorWithParams)
                          throws ClassNotFoundException

Throws:

ClassNotFoundException

newInstance

public static <T> T newInstance(Class<T> clazz,
                                String... params)
                     throws IllegalArgumentException

Create new instance of clazz, call constructor with params as String. Each param is converted to required type for constructor with beanutils converter, first constructor that permit instanciation is used

Type Parameters:

T - type to instanciate

Parameters:

clazz - class to instanciate

params - parameters for constructor call

Returns:

new instance of clazz

Throws:

IllegalArgumentException

getConstructor

public static <T> List<Constructor<T>> getConstructor(Class<T> clazz,
                                                      int paramNumber)

Get all constructors that support paramNumber as parameters numbers. Varargs is supported

Type Parameters:

T - le type de la classe a inspecter

Parameters:

clazz - la classe sur lequel rechercher le constructeur

paramNumber - le nombre de parametre souhaite pour le constructeur, -1 indique que tous les constructeur sont souhaite.

Returns:

list of constructors

toObject

public static Object toObject(Object o)

Method toObject

Parameters:

o - Object to transform

Returns:

the same object

toObject

public static Object toObject(char c)

Method toObject

transform a char to a Character Object

Parameters:

c - the char to transform

Returns:

the Charactere object corresponding

toObject

public static Object toObject(byte b)

Method toObject

transform a byte to a Byte Object

Parameters:

b - the byte to transform

Returns:

the byte object corresponding

toObject

public static Object toObject(short s)

Method toObject

transform a short to a Short object

Parameters:

s - the short to transform

Returns:

the Short object corresponding

toObject

public static Object toObject(int i)

Method toObject

transform an int to an Integer object

Parameters:

i - the int to transform

Returns:

the Integer Object corresponding

toObject

public static Object toObject(long l)

Method toObject

transform a long to a Long object

Parameters:

l - the long to transform

Returns:

the Long Object corresponding

toObject

public static Object toObject(float f)

Method toObject

transform a float to a Float Object

Parameters:

f - the float to transform

Returns:

the Float Object corresponding

toObject

public static Object toObject(double d)

Method toObject

transform a double to a Double object

Parameters:

d - the double to transform

Returns:

the Double object corresponding

toObject

public static Object toObject(boolean b)

Method toObject

transform a boolean to a Boolean object

Parameters:

b - the boolean to transform

Returns:

the Boolean object corresponding

getNullValue

public static Object getNullValue(Class<?> type)

Obtains the null value for the given type (works too with primitive types).

Parameters:

type - the type to test

Returns:

the null value or default value for primitive types

Since:

1.1.5

isNullValue

public static boolean isNullValue(Object value)

Tests if the given value is null according to default value for primitive types if nedded.

Parameters:

value - the value to test

Returns:

true if value is null or default value on a primitive

Since:

1.1.5

isNullValue

public static boolean isNullValue(boolean value)

isNullValue

public static boolean isNullValue(byte value)

isNullValue

public static boolean isNullValue(int value)

isNullValue

public static boolean isNullValue(char value)

isNullValue

public static boolean isNullValue(float value)

isNullValue

public static boolean isNullValue(double value)

isPrimitive

public static boolean isPrimitive(Class<?> clazz)

Verifie si la classe est de type primitif.

Parameters:

clazz - nom de la classe a tester

Returns:

vrai si le classe est de type primitif faux sinon

getPrimitiveClass

public static Class<?> getPrimitiveClass(Class<?> clazz)

Retourne la classe du type primitf associé avec la classe de de l'objet passé en parametre. Par exemple si la classe passée en paramètre est Integer alors le resultat sera la classe de int.

Parameters:

clazz - la classe dont on souhaite le type primitf

Returns:

le type primitif associé a la classe en paramètre, ou null s'il n'y a pas de type primitif associé.