java.lang.Class
Instances of the class Class represent classes and interfaces in a running Java application. An enum type and a record type are classes; an annotation type is a kind of interface. Every array also belongs to a class that is reflected as a Class object shared by all arrays with the same element type and a number of dimensions. The primitive Java types(boolean, byte, char, short, int, long, float, and double), and the keyword void are also represented as Class objects.
The class has no public constructor. Instead, a Class object is constructed automatically by the Java Virtual
The machine when a class is derived from the bytes of a class file through the invocation of one of the following methods:
1. ClassLoader::defineClass.
2. java.lang.invoke.MethodHandles.Lookup::defineClass.
3 java.lang.invoke.MethodHandles.Lookup::defineHiddenClass
The methods of class Class expose many characteristics of a class or interface. Most characteristics are derived from the class file that the class loader passed to the Java Virtual Machine or from the class file passed to Lookup::defineClassor Lookup::defineHiddenClass.A few characteristics are determined by the class loading environment at run time, such as the module returned by getModule().
Implemented Interfaces:
Serializable
AnnotatedElement
GenericDeclaration
Type
Some methods of Class
getDeclaredConstructors(): This method returns an array of Constructor objects reflecting all the constructors declared by the class represented by this Class object.
getDeclaredField(String): This method returns a Field object that reflects the specified field of the class or interface represented by this Class object.
getDeclaredFields(): This method returns an array of Field objects reflecting all the fields declared by the class or interface represented by this Class object.
getDeclaredMethod(String, Class...): This method returns a Method object that reflects the specified declared method of the class or interface represented by this Class object.
getDeclaredMethods(): This method returns an array containing Method objects reflecting all the declared methods of the class or interface represented by this Class object, including public, protected, default (package) access, and private methods, but excluding inherited methods.
getDeclaringClass(): If the class or interface represented by this Class object is a member of another class, returns the Class object representing the class in which it was declared.
getEnclosingClass(): This method returns the immediately enclosing class of the underlying class.
getEnclosingConstructor(): If this Class object represents a local or anonymous class within a constructor, returns a Constructor object representing the immediately enclosing constructor of the underlying class.
getEnclosingMethod(): If this Class object represents a local or anonymous class within a method, returns a Method object representing the immediately enclosing method of the underlying class.
getEnumConstants(): This method returns the elements of this enum class or null if this class object does not represent an enum type.
getField(String): his method returns a Field object that reflects the specified public member field of the class or interface represented by this Class object.
getFields(): This method returns an array containing Field objects reflecting all the accessible public fields of the class or interface represented by this Class object.
getGenericInterfaces(): This method returns the Types representing the interfaces directly implemented by the class or interface represented by this Class object.
getGenericSuperclass(): This method returns the Type representing the direct superclass of the entity (class, interface, primitive type, or void) represented by this Class object.
getInterfaces(): This method returns the interfaces directly implemented by the class or interface represented by this Class object.
getMethod(String, Class...): This method returns a Method object that reflects the specified public member method of the class or interface represented by this Class object.
getModifiers(): This method returns the Java language modifiers for this class or interface, encoded in an integer.
getModule(): This method returns the module that this class or interface is a member of.
getName(): This method returns the name of the entity (class, interface, array class, primitive type, or void) represented by this Class object.
getNestHost(): This method returns the nest host of the nest to which the class or interface represented by this Class object belongs.
getNestMembers(): This method returns an array containing Class objects representing all the classes and interfaces that are members of the nest to which the class or interface represented by this Class object belongs.
getPackage(): This method gets the package of this class.
getPackageName(): This method returns the fully qualified package name.
getProtectionDomain(): This method returns the ProtectionDomain of this class.
getRecordComponents(): This method returns an array of RecordComponent objects representing all the record components of this record class, or null if this class is not a record class.
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