java.lang.reflect - Constructor<T> Class


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Introduction

The java.lang.reflect.Constructor class provides information about, and access to, a single constructor for a class. Constructor permits widening conversions to occur when matching the actual parameters to newInstance() with the underlying constructor's formal parameters, but throws an IllegalArgumentException if a narrowing conversion would occur.

Class declaration

Following is the declaration for java.lang.reflect.Constructor class −

public final class Constructor<T>
   extends AccessibleObject
      implements GenericDeclaration, Member

Class methods

Sr.No. Method & Description
1 boolean equals(Object obj)

Compares this Constructor against the specified object.

2 <T extends Annotation> T getAnnotation(Class<T> annotationClass)

Returns this element's annotation for the specified type if such an annotation is present, else null.

3 Annotation[] getDeclaredAnnotations()

Returns all annotations that are directly present on this element.

4 Class<T> getDeclaringClass()

Returns the Class object representing the class that declares the constructor represented by this Constructor object.

5 Class<?>[] getExceptionTypes()

Returns an array of Class objects that represent the types of exceptions declared to be thrown by the underlying constructor represented by this Constructor object.

6 Type[] getGenericExceptionTypes()

Returns an array of Type objects that represent the exceptions declared to be thrown by this Constructor object.

7 Type[] getGenericParameterTypes()

Returns an array of Type objects that represent the formal parameter types, in declaration order, of the method represented by this Constructor object.

8 int getModifiers()

Returns the Java language modifiers for the constructor represented by this Constructor object, as an integer.

9 String getName()

Returns the name of this constructor, as a string.

10 Annotation[][] getParameterAnnotations()

Returns an array of arrays that represent the annotations on the formal parameters, in declaration order, of the method represented by this Constructor object.

11 Class<?>[] getParameterTypes()

Returns an array of Class objects that represent the formal parameter types, in declaration order, of the constructor represented by this Constructor object.

12 int hashCode()

Returns a hashcode for this Constructor.

13 boolean isSynthetic()

Returns true if this constructor is a synthetic constructor; returns false otherwise.

14 boolean isVarArgs()

Returns true if this constructor was declared to take a variable number of arguments; returns false otherwise.

15 T newInstance(Object... initargs)

Uses the constructor represented by this Constructor object to create and initialize a new instance of the constructor's declaring class, with the specified initialization parameters.

16 String toGenericString()

Returns a string describing this Constructor, including type parameters.

17 String toString()

Returns a string describing this Constructor.

Methods inherited

This class inherits methods from the following classes −

  • java.lang.reflect.AccessibleObject
  • java.lang.Object


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