Package java.lang.reflect

Class Constructor<T>

    • Method Detail

      • getAnnotations

        public Annotation[] getAnnotations()
        Description copied from interface: AnnotatedElement
        Returns, for this element, an array containing all annotations (including inherited annotations). If there are no annotations present, this method returns a zero length array.
        Specified by:
        getAnnotations in interface AnnotatedElement
        Overrides:
        getAnnotations in class AbstractMethod
        Returns:
        an array of all annotations for this element

      • getModifiers

        public int getModifiers()
        Returns the modifiers for this constructor. The Modifier class should be used to decode the result.
        Specified by:
        getModifiers in interface Member
        Returns:
        the modifiers for this member
        See Also:
        Modifier

      • isVarArgs

        public boolean isVarArgs()
        Returns true if this constructor takes a variable number of arguments.

      • isSynthetic

        public boolean isSynthetic()
        Returns true if this constructor is synthetic (artificially introduced by the compiler).
        Specified by:
        isSynthetic in interface Member
        Returns:
        true if this member is synthetic, false otherwise

      • getDeclaringClass

        public Class<T> getDeclaringClass()
        Returns the class that declares this constructor.
        Specified by:
        getDeclaringClass in interface Member
        Returns:
        the declaring class

      • getExceptionTypes

        public Class<?>[] getExceptionTypes()
        Returns the exception types as an array of Class instances. If this constructor has no declared exceptions, an empty array will be returned.

      • getParameterTypes

        public Class<?>[] getParameterTypes()
        Returns an array of the Class objects associated with the parameter types of this constructor. If the constructor was declared with no parameters, an empty array will be returned.

      • hashCode

        public int hashCode()
        Returns an integer hash code for this object. By contract, any two objects for which Object.equals(java.lang.Object) returns true must return the same hash code value. This means that subclasses of Object usually override both methods or neither method.

        Note that hash values must not change over time unless information used in equals comparisons also changes.

        See Writing a correct hashCode method if you intend implementing your own hashCode method.

        Equivalent to getDeclaringClass().getName().hashCode().

        Overrides:
        hashCode in class Object
        Returns:
        this object's hash code.
        See Also:
        Object.equals(java.lang.Object)

      • equals

        public boolean equals​(Object other)
        Returns true if other has the same declaring class and parameters as this constructor.
        Overrides:
        equals in class AbstractMethod
        Parameters:
        other - the object to compare this instance with.
        Returns:
        true if the specified object is equal to this Object; false otherwise.
        See Also:
        Object.hashCode()

      • getTypeParameters

        public TypeVariable<Constructor<T>>[] getTypeParameters()
        Description copied from interface: GenericDeclaration
        Returns the declared type parameters in declaration order. If there are no type parameters, this method returns a zero length array.
        Specified by:
        getTypeParameters in interface GenericDeclaration
        Returns:
        the declared type parameters in declaration order

      • toGenericString

        public String toGenericString()
        Returns the string representation of the constructor's declaration, including the type parameters.
        Returns:
        the string representation of the constructor's declaration

      • getGenericParameterTypes

        public Type[] getGenericParameterTypes()
        Returns the generic parameter types as an array of Type instances, in declaration order. If this constructor has no generic parameters, an empty array is returned.
        Returns:
        the parameter types
        Throws:
        GenericSignatureFormatError - if the generic constructor signature is invalid
        TypeNotPresentException - if any parameter type points to a missing type
        MalformedParameterizedTypeException - if any parameter type points to a type that cannot be instantiated for some reason

      • getGenericExceptionTypes

        public Type[] getGenericExceptionTypes()
        Returns the exception types as an array of Type instances. If this constructor has no declared exceptions, an empty array will be returned.
        Returns:
        an array of generic exception types
        Throws:
        GenericSignatureFormatError - if the generic constructor signature is invalid
        TypeNotPresentException - if any exception type points to a missing type
        MalformedParameterizedTypeException - if any exception type points to a type that cannot be instantiated for some reason

      • isAnnotationPresent

        public boolean isAnnotationPresent​(Class<? extends Annotation> annotationType)
        Description copied from interface: AnnotatedElement
        Indicates whether or not this element has an annotation with the specified annotation type (including inherited annotations).
        Specified by:
        isAnnotationPresent in interface AnnotatedElement
        Overrides:
        isAnnotationPresent in class AbstractMethod
        Parameters:
        annotationType - the type of the annotation to search for
        Returns:
        true if the annotation exists, false otherwise

      • getAnnotation

        public <A extends Annotation> A getAnnotation​(Class<A> annotationType)
        Description copied from interface: AnnotatedElement
        Returns, for this element, the annotation with the specified type, or null if no annotation with the specified type is present (including inherited annotations).
        Specified by:
        getAnnotation in interface AnnotatedElement
        Overrides:
        getAnnotation in class AbstractMethod
        Parameters:
        annotationType - the type of the annotation to search for
        Returns:
        the annotation with the specified type or null

      • getParameterAnnotations

        public Annotation[][] getParameterAnnotations()
        Returns an array of arrays that represent the annotations of the formal parameters of this constructor. If there are no parameters on this constructor, then an empty array is returned. If there are no annotations set, then an array of empty arrays is returned.
        Specified by:
        getParameterAnnotations in class AbstractMethod
        Returns:
        an array of arrays of Annotation instances

      • newInstance

        public T newInstance​(Object... args)
              throws InstantiationException,
                     IllegalAccessException,
                     IllegalArgumentException,
                     InvocationTargetException
        Returns a new instance of the declaring class, initialized by dynamically invoking the constructor represented by this Constructor object. This reproduces the effect of new declaringClass(arg1, arg2, ... , argN) This method performs the following:
        • A new instance of the declaring class is created. If the declaring class cannot be instantiated (i.e. abstract class, an interface, an array type, or a primitive type) then an InstantiationException is thrown.
        • If this Constructor object is enforcing access control (see AccessibleObject) and this constructor is not accessible from the current context, an IllegalAccessException is thrown.
        • If the number of arguments passed and the number of parameters do not match, an IllegalArgumentException is thrown.
        • For each argument passed:
          • If the corresponding parameter type is a primitive type, the argument is unboxed. If the unboxing fails, an IllegalArgumentException is thrown.
          • If the resulting argument cannot be converted to the parameter type via a widening conversion, an IllegalArgumentException is thrown.
        • The constructor represented by this Constructor object is then invoked. If an exception is thrown during the invocation, it is caught and wrapped in an InvocationTargetException. This exception is then thrown. If the invocation completes normally, the newly initialized object is returned.
        Parameters:
        args - the arguments to the constructor
        Returns:
        the new, initialized, object
        Throws:
        InstantiationException - if the class cannot be instantiated
        IllegalAccessException - if this constructor is not accessible
        IllegalArgumentException - if an incorrect number of arguments are passed, or an argument could not be converted by a widening conversion
        InvocationTargetException - if an exception was thrown by the invoked constructor
        See Also:
        AccessibleObject

      • toString

        public String toString()
        Returns a string containing a concise, human-readable description of this constructor. The format of the string is:
        1. modifiers (if any)
        2. declaring class name
        3. '('
        4. parameter types, separated by ',' (if any)
        5. ')'
        6. 'throws' plus exception types, separated by ',' (if any)
        For example: public String(byte[],String) throws UnsupportedEncodingException
        Overrides:
        toString in class Object
        Returns:
        a printable representation for this constructor

      • setAccessible

        public void setAccessible​(boolean flag)
        Attempts to set the accessible flag. Setting this to true prevents IllegalAccessExceptions.
        Overrides:
        setAccessible in class AccessibleObject