Class ReflectionUtils

Method Details

• wrapPrimitive

  public static <T> Class<T> wrapPrimitive (Class<T> clazz)

  Wrap given class to it's primitive class if it's matching a primitive class.

  Type Parameters:

  T - type of class

  Parameters:

  clazz - primitive class or not

  Returns:

  class or primitive class

• toClass

  public static Class<?>[] toClass (Object... array)

  Converts an array of Object into an array of Class objects.

  If any of these objects is null, a null element will be inserted into the array.

  This method returns null for a null input array.

  Parameters:

  array - an Object array

  Returns:

  a Class array, null if null array input

• toArgs

  public static Object[] toArgs (Function<Class<?>,Object> valueSupplier, Class<?>... array)

  Converts an array of values provided by an array of Class and Function supplying value for each class into an array of Object

  Parameters:

  valueSupplier - supplier of values for each class

  array - array of class

  Returns:

  array of values

• getDefault

  public static <T> T getDefault (Class<T> type)

  Get default value for given type.

  Type Parameters:

  T - type of value

  Parameters:

  type - type of value to get the default

  Returns:

  default value

• getConstructor

  public static <T> Constructor<T> getConstructor (Class<T> cls, Class<?>... argsTypes) throws NoSuchMethodException

  Retrieve the constructor of a class for given argument types.

  Type Parameters:

  T - type to retrieve the constructor from

  Parameters:

  cls - class to retrieve the constructor from

  argsTypes - argument types

  Returns:

  matching constructor for given argument values

  Throws:

  NoSuchMethodException - if a matching method is not found.

• getConstructorOptional

  public static <T> Constructor<T> getConstructorOptional (int mandatoryCount, Class<T> cls, Class<?>... argsTypes) throws NoSuchMethodException

  Retrieve the constructor of a class for given optional argument types, considering mandatory values at the beginning of the given types.

  Type Parameters:

  T - type to retrieve the constructor from

  Parameters:

  mandatoryCount - number of mandatory arguments at the beginning of the given arguments

  cls - class to retrieve the constructor from

  argsTypes - argument types

  Returns:

  matching constructor for given optional argument values

  Throws:

  NoSuchMethodException - if a matching method is not found.

• newInstance

  public static <T> T newInstance (Class<T> cls, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException, InstantiationException

  Creates a new instance matching possible constructors with provided args.

  Type Parameters:

  T - type of the instance

  Parameters:

  cls - class to instantiate

  args - arguments of the constructor

  Returns:

  new instance

  Throws:

  NoSuchMethodException - if a matching method is not found.

  IllegalAccessException - if this Constructor object is enforcing Java language access control and the underlying constructor is inaccessible.

  InstantiationException - if the class that declares the underlying constructor represents an abstract class.

  InvocationTargetException - if the underlying constructor throws an exception.

• newInstanceOptionalArgs

  public static <T> T newInstanceOptionalArgs (Class<T> cls, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException, InstantiationException

  Creates a new instance by trying every possible constructors with provided args.

  Type Parameters:

  T - type of the instance

  Parameters:

  cls - class to instantiate

  args - arguments of the constructor

  Returns:

  new instance

  Throws:

  NoSuchMethodException - if a matching method is not found.

  IllegalAccessException - if this Constructor object is enforcing Java language access control and the underlying constructor is inaccessible.

  InstantiationException - if the class that declares the underlying constructor represents an abstract class.

  InvocationTargetException - if the underlying constructor throws an exception.

• newInstanceOptionalArgs

  public static <T> T newInstanceOptionalArgs (int mandatoryCount, Class<T> cls, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException, InstantiationException

  Creates a new instance by trying every possible constructors with provided args.

  Type Parameters:

  T - type of the instance

  Parameters:

  mandatoryCount - count of mandatory arguments

  cls - class to instantiate

  args - arguments of the constructor

  Returns:

  new instance

  Throws:

  NoSuchMethodException - if a matching method is not found.

  IllegalAccessException - if this Constructor object is enforcing Java language access control and the underlying constructor is inaccessible.

  InstantiationException - if the class that declares the underlying constructor represents an abstract class.

  InvocationTargetException - if the underlying constructor throws an exception.

• invoke

  public static Object invoke (Method method, Object obj, Object... args) throws InvocationTargetException, IllegalAccessException

  Invoke the method event if not accessible.

  Parameters:

  method - method to invoke

  obj - object to invoke

  args - arguments of the method

  Returns:

  return value from the method invocation

  Throws:

  IllegalAccessException - if this Method object is enforcing Java language access control and the underlying method is inaccessible.

  InvocationTargetException - if the underlying method throws an exception.

  See Also:

  • Method.invoke(Object, Object...)

• get

  public static Object get (Field field, Object obj) throws IllegalAccessException

  Get the field value even if not accessible.

  Parameters:

  field - field to get

  obj - instance to get

  Returns:

  field value

  Throws:

  IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible.

  See Also:

  • Field.get(Object)

• set

  public static void set (Field field, Object obj, Object value) throws IllegalAccessException

  Set the field even if not accessible.

  Parameters:

  field - field to set

  obj - instance to set

  value - value of the field to set

  Throws:

  IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final.

  See Also:

  • Field.set(Object, Object)

• getFirstGenericType

  public static Class<?> getFirstGenericType (Field field)

  Retrieve the first generic type of the field type.

  Parameters:

  field - field to analyze

  Returns:

  first generic type, or null if no generic type is found

• getMethod

  public static Method getMethod (Class<?> declaringClass, String name, Class... types)

  Get public method by name from the declaring class.

  Parameters:

  declaringClass - declaring class

  name - method name

  types - argument types

  Returns:

  the public method by the specified name

  Throws:

  IllegalArgumentException - when there is no method found with the specified name