java.lang

Class Class<T>

public final class Class<T> extends Object implements Serializable, Type, AnnotatedElement, GenericDeclaration

A Class represents a Java type. There will never be multiple Class objects with identical names and ClassLoaders. Primitive types, array types, and void also have a Class object.

Arrays with identical type and number of dimensions share the same class. The array class ClassLoader is the same as the ClassLoader of the element type of the array (which can be null to indicate the bootstrap classloader). The name of an array class is [<signature format>;.

For example, String[]'s class is [Ljava.lang.String;. boolean, byte, short, char, int, long, float and double have the "type name" of Z,B,S,C,I,J,F,D for the purposes of array classes. If it's a multidimensioned array, the same principle applies: int[][][] == [[[I.

There is no public constructor - Class objects are obtained only through the virtual machine, as defined in ClassLoaders.

Serial Data: Class objects serialize specially: TC_CLASS ClassDescriptor. For more serialization information, see {@link ObjectStreamClass}.

Since: 1.0

Method Summary
<U> Class<? extends U>	asSubclass(Class<U> klass) Casts this class to represent a subclass of the specified class.
T	cast(Object obj) Returns the specified object, cast to this `Class`' type.
boolean	desiredAssertionStatus() Returns the desired assertion status of this class, if it were to be initialized at this moment.
static Class<?>	forName(String name) Use the classloader of the current class to load, link, and initialize a class.
static Class<?>	forName(String name, boolean initialize, ClassLoader classloader) Use the specified classloader to load and link a class.
<A extends Annotation> A	getAnnotation(Class<A> annotationClass) Returns this class' annotation for the specified annotation type, or `null` if no such annotation exists.
Annotation[]	getAnnotations() Returns all annotations associated with this class.
String	getCanonicalName() Returns the canonical name of this class, as defined by section 6.7 of the Java language specification.
Class<?>[]	getClasses() Get all the public member classes and interfaces declared in this class or inherited from superclasses.
ClassLoader	getClassLoader() Get the ClassLoader that loaded this class.
Class<?>	getComponentType() If this is an array, get the Class representing the type of array.
Constructor<T>	getConstructor(Class<?>... types) Get a public constructor declared in this class.
Constructor<?>[]	getConstructors() Get all the public constructors of this class.
Annotation[]	getDeclaredAnnotations() Returns all annotations directly defined by this class.
Class<?>[]	getDeclaredClasses() Get all the declared member classes and interfaces in this class, but not those inherited from superclasses.
Constructor<T>	getDeclaredConstructor(Class<?>... types) Get a constructor declared in this class.
Constructor<?>[]	getDeclaredConstructors() Get all the declared constructors of this class.
Field	getDeclaredField(String name) Get a field declared in this class, where name is its simple name.
Field[]	getDeclaredFields() Get all the declared fields in this class, but not those inherited from superclasses.
Method	getDeclaredMethod(String methodName, Class<?>... types) Get a method declared in this class, where name is its simple name.
Method[]	getDeclaredMethods() Get all the declared methods in this class, but not those inherited from superclasses.
Class<?>	getDeclaringClass() If this is a nested or inner class, return the class that declared it.
Class<?>	getEnclosingClass() Returns the class which immediately encloses this class.
Constructor<?>	getEnclosingConstructor() Returns the constructor which immediately encloses this class.
Method	getEnclosingMethod() Returns the method which immediately encloses this class.
T[]	getEnumConstants() Returns the enumeration constants of this class, or null if this class is not an `Enum`.
Field	getField(String fieldName) Get a public field declared or inherited in this class, where name is its simple name.
Field[]	getFields() Get all the public fields declared in this class or inherited from superclasses.
Type[]	getGenericInterfaces() Returns an array of `Type` objects which represent the interfaces directly implemented by this class or extended by this interface.
Type	getGenericSuperclass() Returns a `Type` object representing the direct superclass, whether class, interface, primitive type or void, of this class.
Class<?>[]	getInterfaces() Get the interfaces this class directly implements, in the order that they were declared.
Method	getMethod(String methodName, Class<?>... types) Get a public method declared or inherited in this class, where name is its simple name.
Method[]	getMethods() Get all the public methods declared in this class or inherited from superclasses.
int	getModifiers() Get the modifiers of this class.
String	getName() Get the name of this class, separated by dots for package separators.
Package	getPackage() Returns the `Package` in which this class is defined Returns null when this information is not available from the classloader of this class.
ProtectionDomain	getProtectionDomain() Returns the protection domain of this class.
URL	getResource(String resourceName) Get a resource URL using this class's package using the getClassLoader().getResource() method.
InputStream	getResourceAsStream(String resourceName) Get a resource using this class's package using the getClassLoader().getResourceAsStream() method.
Object[]	getSigners() Get the signers of this class.
String	getSimpleName() Returns the simple name for this class, as used in the source code.
Class<? super T>	getSuperclass() Get the direct superclass of this class.
TypeVariable<Class<T>>[]	getTypeParameters() Returns an array of `TypeVariable` objects that represents the type variables declared by this class, in declaration order.
boolean	isAnnotation() Returns true if this class is an `Annotation`.
boolean	isAnnotationPresent(Class<? extends Annotation> annotationClass) Returns true if an annotation for the specified type is associated with this class.
boolean	isAnonymousClass() Returns true if this object represents an anonymous class.
boolean	isArray() Return whether this class is an array type.
boolean	isAssignableFrom(Class<?> c) Discover whether an instance of the Class parameter would be an instance of this Class as well.
boolean	isEnum() Returns true if this class is an `Enum`.
boolean	isInstance(Object o) Discover whether an Object is an instance of this Class.
boolean	isInterface() Check whether this class is an interface or not.
boolean	isLocalClass() Returns true if this object represents an local class.
boolean	isMemberClass() Returns true if this object represents an member class.
boolean	isPrimitive() Return whether this class is a primitive type.
boolean	isSynthetic() Returns true if this class is a synthetic class, generated by the compiler.
T	newInstance() Get a new instance of this class by calling the no-argument constructor.
String	toString() Return the human-readable form of this Object.

Method Detail

asSubclass

public <U> Class<? extends U> asSubclass(Class<U> klass)

Casts this class to represent a subclass of the specified class. This method is useful for `narrowing' the type of a class so that the class object, and instances of that class, can match the contract of a more restrictive method. For example, if this class has the static type of Class<Object>, and a dynamic type of Class<Rectangle>, then, assuming Shape is a superclass of Rectangle, this method can be used on this class with the parameter, Class<Shape>, to retain the same instance but with the type Class<? extends Shape>.

If this class can be converted to an instance which is parameterised over a subtype of the supplied type, U, then this method returns an appropriately cast reference to this object. Otherwise, a ClassCastException is thrown.

Parameters: klass the class object, the parameterized type (U) of which should be a superclass of the parameterized type of this instance.

Returns: a reference to this object, appropriately cast.

Throws: ClassCastException if this class can not be converted to one which represents a subclass of the specified type, U.

Since: 1.5

cast

public T cast(Object obj)

Returns the specified object, cast to this Class' type.

Parameters: obj the object to cast

Throws: ClassCastException if obj is not an instance of this class

Since: 1.5

desiredAssertionStatus

public boolean desiredAssertionStatus()

Returns the desired assertion status of this class, if it were to be initialized at this moment. The class assertion status, if set, is returned; the backup is the default package status; then if there is a class loader, that default is returned; and finally the system default is returned. This method seldom needs calling in user code, but exists for compilers to implement the assert statement. Note that there is no guarantee that the result of this method matches the class's actual assertion status.

Returns: the desired assertion status

Since: 1.4

forName

public static Class<?> forName(String name)

Use the classloader of the current class to load, link, and initialize a class. This is equivalent to your code calling Class.forName(name, true, getClass().getClassLoader()).

Parameters: name the name of the class to find

Returns: the Class object representing the class

forName

public static Class<?> forName(String name, boolean initialize, ClassLoader classloader)

Use the specified classloader to load and link a class. If the loader is null, this uses the bootstrap class loader (provide the security check succeeds). Unfortunately, this method cannot be used to obtain the Class objects for primitive types or for void, you have to use the fields in the appropriate java.lang wrapper classes.

Calls classloader.loadclass(name, initialize).

Parameters: name the name of the class to find initialize whether or not to initialize the class at this time classloader the classloader to use to find the class; null means to use the bootstrap class loader

Returns: the class object for the given class

Throws: ClassNotFoundException if the class was not found by the classloader LinkageError if linking the class fails ExceptionInInitializerError if the class loads, but an exception occurs during initialization SecurityException if the classloader argument is null and the caller does not have the RuntimePermission("getClassLoader") permission

Since: 1.2

getAnnotation

public <A extends Annotation> A getAnnotation(Class<A> annotationClass)

Returns this class' annotation for the specified annotation type, or null if no such annotation exists.

Parameters: annotationClass the type of annotation to look for.

Returns: this class' annotation for the specified type, or null if no such annotation exists.

Since: 1.5

getAnnotations

public Annotation[] getAnnotations()

Returns all annotations associated with this class. If there are no annotations associated with this class, then a zero-length array will be returned. The returned array may be modified by the client code, but this will have no effect on the annotation content of this class, and hence no effect on the return value of this method for future callers.

Returns: this class' annotations.

Since: 1.5

getCanonicalName

public String getCanonicalName()

Returns the canonical name of this class, as defined by section 6.7 of the Java language specification. Each package, top-level class, top-level interface and primitive type has a canonical name. A member class has a canonical name, if its parent class has one. Likewise, an array type has a canonical name, if its component type does. Local or anonymous classes do not have canonical names.

The canonical name for top-level classes, top-level interfaces and primitive types is always the same as the fully-qualified name. For array types, the canonical name is the canonical name of its component type with `[]' appended.

The canonical name of a member class always refers to the place where the class was defined, and is composed of the canonical name of the defining class and the simple name of the member class, joined by `.'. For example, if a Person class has an inner class, M, then both its fully-qualified name and canonical name is Person.M. A subclass, Staff, of Person refers to the same inner class by the fully-qualified name of Staff.M, but its canonical name is still Person.M.

Where no canonical name is present, null is returned.

Returns: the canonical name of the class, or null if the class doesn't have a canonical name.

Since: 1.5

getClasses

public Class<?>[] getClasses()

Get all the public member classes and interfaces declared in this class or inherited from superclasses. This returns an array of length 0 if there are no member classes, including for primitive types. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Returns: all public member classes in this class

Throws: SecurityException if the security check fails

Since: 1.1

getClassLoader

public ClassLoader getClassLoader()

Get the ClassLoader that loaded this class. If the class was loaded by the bootstrap classloader, this method will return null. If there is a security manager, and the caller's class loader is not an ancestor of the requested one, a security check of RuntimePermission("getClassLoader") must first succeed. Primitive types and void return null.

Returns: the ClassLoader that loaded this class

Throws: SecurityException if the security check fails

getComponentType

public Class<?> getComponentType()

If this is an array, get the Class representing the type of array. Examples: "[[Ljava.lang.String;" would return "[Ljava.lang.String;", and calling getComponentType on that would give "java.lang.String". If this is not an array, returns null.

Returns: the array type of this class, or null

Since: 1.1

getConstructor

public Constructor<T> getConstructor(Class<?>... types)

Get a public constructor declared in this class. If the constructor takes no argument, an array of zero elements and null are equivalent for the types argument. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Parameters: types the type of each parameter

Returns: the constructor

Throws: NoSuchMethodException if the constructor does not exist SecurityException if the security check fails

Since: 1.1

getConstructors

public Constructor<?>[] getConstructors()

Get all the public constructors of this class. This returns an array of length 0 if there are no constructors, including for primitive types, arrays, and interfaces. It does, however, include the default constructor if one was supplied by the compiler. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Returns: all public constructors in this class

Throws: SecurityException if the security check fails

Since: 1.1

getDeclaredAnnotations

public Annotation[] getDeclaredAnnotations()

Returns all annotations directly defined by this class. If there are no annotations associated with this class, then a zero-length array will be returned. The returned array may be modified by the client code, but this will have no effect on the annotation content of this class, and hence no effect on the return value of this method for future callers.

Returns: the annotations directly defined by this class.

Since: 1.5

getDeclaredClasses

public Class<?>[] getDeclaredClasses()

Get all the declared member classes and interfaces in this class, but not those inherited from superclasses. This returns an array of length 0 if there are no member classes, including for primitive types. A security check may be performed, with checkMemberAccess(this, Member.DECLARED) as well as checkPackageAccess both having to succeed.

Returns: all declared member classes in this class

Throws: SecurityException if the security check fails

Since: 1.1

getDeclaredConstructor

public Constructor<T> getDeclaredConstructor(Class<?>... types)

Get a constructor declared in this class. If the constructor takes no argument, an array of zero elements and null are equivalent for the types argument. A security check may be performed, with checkMemberAccess(this, Member.DECLARED) as well as checkPackageAccess both having to succeed.

Parameters: types the type of each parameter

Returns: the constructor

Throws: NoSuchMethodException if the constructor does not exist SecurityException if the security check fails

Since: 1.1

getDeclaredConstructors

public Constructor<?>[] getDeclaredConstructors()

Get all the declared constructors of this class. This returns an array of length 0 if there are no constructors, including for primitive types, arrays, and interfaces. It does, however, include the default constructor if one was supplied by the compiler. A security check may be performed, with checkMemberAccess(this, Member.DECLARED) as well as checkPackageAccess both having to succeed.

Returns: all constructors in this class

Throws: SecurityException if the security check fails

Since: 1.1

getDeclaredField

public Field getDeclaredField(String name)

Get a field declared in this class, where name is its simple name. The implicit length field of arrays is not available. A security check may be performed, with checkMemberAccess(this, Member.DECLARED) as well as checkPackageAccess both having to succeed.

Parameters: name the name of the field

Returns: the field

Throws: NoSuchFieldException if the field does not exist SecurityException if the security check fails

Since: 1.1

getDeclaredFields

public Field[] getDeclaredFields()

Get all the declared fields in this class, but not those inherited from superclasses. This returns an array of length 0 if there are no fields, including for primitive types. This does not return the implicit length field of arrays. A security check may be performed, with checkMemberAccess(this, Member.DECLARED) as well as checkPackageAccess both having to succeed.

Returns: all declared fields in this class

Throws: SecurityException if the security check fails

Since: 1.1

getDeclaredMethod

public Method getDeclaredMethod(String methodName, Class<?>... types)

Get a method declared in this class, where name is its simple name. The implicit methods of Object are not available from arrays or interfaces. Constructors (named "<init>" in the class file) and class initializers (name "<clinit>") are not available. The Virtual Machine allows multiple methods with the same signature but differing return types; in such a case the most specific return types are favored, then the final choice is arbitrary. If the method takes no argument, an array of zero elements and null are equivalent for the types argument. A security check may be performed, with checkMemberAccess(this, Member.DECLARED) as well as checkPackageAccess both having to succeed.

Parameters: methodName the name of the method types the type of each parameter

Returns: the method

Throws: NoSuchMethodException if the method does not exist SecurityException if the security check fails

Since: 1.1

getDeclaredMethods

public Method[] getDeclaredMethods()

Get all the declared methods in this class, but not those inherited from superclasses. This returns an array of length 0 if there are no methods, including for primitive types. This does include the implicit methods of arrays and interfaces which mirror methods of Object, nor does it include constructors or the class initialization methods. The Virtual Machine allows multiple methods with the same signature but differing return types; all such methods are in the returned array. A security check may be performed, with checkMemberAccess(this, Member.DECLARED) as well as checkPackageAccess both having to succeed.

Returns: all declared methods in this class

Throws: SecurityException if the security check fails

Since: 1.1

getDeclaringClass

public Class<?> getDeclaringClass()

If this is a nested or inner class, return the class that declared it. If not, return null.

Returns: the declaring class of this class

Since: 1.1

getEnclosingClass

public Class<?> getEnclosingClass()

Returns the class which immediately encloses this class. If this class is a top-level class, this method returns null.

Returns: the immediate enclosing class, or null if this is a top-level class.

Since: 1.5

getEnclosingConstructor

public Constructor<?> getEnclosingConstructor()

Returns the constructor which immediately encloses this class. If this class is a top-level class, or a local or anonymous class immediately enclosed by a type definition, instance initializer or static initializer, then null is returned.

Returns: the immediate enclosing constructor if this class is declared within a constructor. Otherwise, null is returned.

Since: 1.5

getEnclosingMethod

public Method getEnclosingMethod()

Returns the method which immediately encloses this class. If this class is a top-level class, or a local or anonymous class immediately enclosed by a type definition, instance initializer or static initializer, then null is returned.

Returns: the immediate enclosing method if this class is declared within a method. Otherwise, null is returned.

Since: 1.5

getEnumConstants

public T[] getEnumConstants()

Returns the enumeration constants of this class, or null if this class is not an Enum.

Returns: an array of Enum constants associated with this class, or null if this class is not an enum.

Since: 1.5

getField

public Field getField(String fieldName)

Get a public field declared or inherited in this class, where name is its simple name. If the class contains multiple accessible fields by that name, an arbitrary one is returned. The implicit length field of arrays is not available. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Parameters: fieldName the name of the field

Returns: the field

Throws: NoSuchFieldException if the field does not exist SecurityException if the security check fails

Since: 1.1

getFields

public Field[] getFields()

Get all the public fields declared in this class or inherited from superclasses. This returns an array of length 0 if there are no fields, including for primitive types. This does not return the implicit length field of arrays. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Returns: all public fields in this class

Throws: SecurityException if the security check fails

Since: 1.1

getGenericInterfaces

public Type[] getGenericInterfaces()

Returns an array of Type objects which represent the interfaces directly implemented by this class or extended by this interface.

If one of the superinterfaces is a parameterized type, then the object returned for this interface reflects the actual type parameters used in the source code. Type parameters are created using the semantics specified by the ParameterizedType interface, and only if an instance has not already been created.

The order of the interfaces in the array matches the order in which the interfaces are declared. For classes which represent an array, an array of two interfaces, Cloneable and Serializable, is always returned, with the objects in that order. A class representing a primitive type or void always returns an array of zero size.

Returns: an array of interfaces implemented or extended by this class.

Throws: GenericSignatureFormatError if the generic signature of one of the interfaces does not comply with that specified by the Java Virtual Machine specification, 3rd edition. TypeNotPresentException if any of the superinterfaces refers to a non-existant type. MalformedParameterizedTypeException if any of the interfaces refer to a parameterized type that can not be instantiated for some reason.

Since: 1.5

getGenericSuperclass

public Type getGenericSuperclass()

Returns a Type object representing the direct superclass, whether class, interface, primitive type or void, of this class. If this class is an array class, then a class instance representing the Object class is returned. If this class is primitive, an interface, or a representation of either the Object class or void, then null is returned.

If the superclass is a parameterized type, then the object returned for this interface reflects the actual type parameters used in the source code. Type parameters are created using the semantics specified by the ParameterizedType interface, and only if an instance has not already been created.

Returns: the superclass of this class.

Throws: GenericSignatureFormatError if the generic signature of the class does not comply with that specified by the Java Virtual Machine specification, 3rd edition. TypeNotPresentException if the superclass refers to a non-existant type. MalformedParameterizedTypeException if the superclass refers to a parameterized type that can not be instantiated for some reason.

Since: 1.5

getInterfaces

public Class<?>[] getInterfaces()

Get the interfaces this class directly implements, in the order that they were declared. This returns an empty array, not null, for Object, primitives, void, and classes or interfaces with no direct superinterface. Array types return Cloneable and Serializable.

Returns: the interfaces this class directly implements

getMethod

public Method getMethod(String methodName, Class<?>... types)

Get a public method declared or inherited in this class, where name is its simple name. The implicit methods of Object are not available from interfaces. Constructors (named "<init>" in the class file) and class initializers (name "<clinit>") are not available. The Virtual Machine allows multiple methods with the same signature but differing return types, and the class can inherit multiple methods of the same return type; in such a case the most specific return types are favored, then the final choice is arbitrary. If the method takes no argument, an array of zero elements and null are equivalent for the types argument. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Parameters: methodName the name of the method types the type of each parameter

Returns: the method

Throws: NoSuchMethodException if the method does not exist SecurityException if the security check fails

Since: 1.1

getMethods

public Method[] getMethods()

Get all the public methods declared in this class or inherited from superclasses. This returns an array of length 0 if there are no methods, including for primitive types. This does not include the implicit methods of interfaces which mirror methods of Object, nor does it include constructors or the class initialization methods. The Virtual Machine allows multiple methods with the same signature but differing return types; all such methods are in the returned array. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Returns: all public methods in this class

Throws: SecurityException if the security check fails

Since: 1.1

getModifiers

public int getModifiers()

Get the modifiers of this class. These can be decoded using Modifier, and is limited to one of public, protected, or private, and any of final, static, abstract, or interface. An array class has the same public, protected, or private modifier as its component type, and is marked final but not an interface. Primitive types and void are marked public and final, but not an interface.

Returns: the modifiers of this class

Since: 1.1

getName

public String getName()

Get the name of this class, separated by dots for package separators. If the class represents a primitive type, or void, then the name of the type as it appears in the Java programming language is returned. For instance, Byte.TYPE.getName() returns "byte". Arrays are specially encoded as shown on this table.

 array type          [element type
                     (note that the element type is encoded per
                      this table)
 boolean             Z
 byte                B
 char                C
 short               S
 int                 I
 long                J
 float               F
 double              D
 void                V
 class or interface, alone: <dotted name>
 class or interface, as element type: L<dotted name>;

Returns: the name of this class

getPackage

public Package getPackage()

Returns the Package in which this class is defined Returns null when this information is not available from the classloader of this class.

Returns: the package for this class, if it is available

Since: 1.2

getProtectionDomain

public ProtectionDomain getProtectionDomain()

Returns the protection domain of this class. If the classloader did not record the protection domain when creating this class the unknown protection domain is returned which has a null code source and all permissions. A security check may be performed, with RuntimePermission("getProtectionDomain").

Returns: the protection domain

Throws: SecurityException if the security manager exists and the caller does not have RuntimePermission("getProtectionDomain").

Since: 1.2

getResource

public URL getResource(String resourceName)

Get a resource URL using this class's package using the getClassLoader().getResource() method. If this class was loaded using the system classloader, ClassLoader.getSystemResource() is used instead.

If the name you supply is absolute (it starts with a /), then the leading / is removed and it is passed on to getResource(). If it is relative, the package name is prepended, and .'s are replaced with /.

The URL returned is system- and classloader-dependent, and could change across implementations.

Parameters: resourceName the name of the resource, generally a path

Returns: the URL to the resource

Throws: NullPointerException if name is null

Since: 1.1

getResourceAsStream

public InputStream getResourceAsStream(String resourceName)

Get a resource using this class's package using the getClassLoader().getResourceAsStream() method. If this class was loaded using the system classloader, ClassLoader.getSystemResource() is used instead.

The URL returned is system- and classloader-dependent, and could change across implementations.

Parameters: resourceName the name of the resource, generally a path

Returns: an InputStream with the contents of the resource in it, or null

Throws: NullPointerException if name is null

Since: 1.1

getSigners

public Object[] getSigners()

Get the signers of this class. This returns null if there are no signers, such as for primitive types or void.

Returns: the signers of this class

Since: 1.1

getSimpleName

public String getSimpleName()

Returns the simple name for this class, as used in the source code. For normal classes, this is the content returned by getName() which follows the last ".". Anonymous classes have no name, and so the result of calling this method is "". The simple name of an array consists of the simple name of its component type, followed by "[]". Thus, an array with the component type of an anonymous class has a simple name of simply "[]".

Returns: the simple name for this class.

Since: 1.5

getSuperclass

public Class<? super T> getSuperclass()

Get the direct superclass of this class. If this is an interface, Object, a primitive type, or void, it will return null. If this is an array type, it will return Object.

Returns: the direct superclass of this class

getTypeParameters

public TypeVariable<Class<T>>[] getTypeParameters()

Returns an array of TypeVariable objects that represents the type variables declared by this class, in declaration order. An array of size zero is returned if this class has no type variables.

Returns: the type variables associated with this class.

Throws: GenericSignatureFormatError if the generic signature does not conform to the format specified in the Virtual Machine specification, version 3.

Since: 1.5

isAnnotation

public boolean isAnnotation()

Returns true if this class is an Annotation.

Returns: true if this is an annotation class.

Since: 1.5

isAnnotationPresent

public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass)

Returns true if an annotation for the specified type is associated with this class. This is primarily a short-hand for using marker annotations.

Parameters: annotationClass the type of annotation to look for.

Returns: true if an annotation exists for the specified type.

Since: 1.5

isAnonymousClass

public boolean isAnonymousClass()

Returns true if this object represents an anonymous class.

Returns: true if this object represents an anonymous class.

Since: 1.5

isArray

public boolean isArray()

Return whether this class is an array type.

Returns: whether this class is an array type

Since: 1.1

isAssignableFrom

public boolean isAssignableFrom(Class<?> c)

Discover whether an instance of the Class parameter would be an instance of this Class as well. Think of doing isInstance(c.newInstance()) or even c.newInstance() instanceof (this class). While this checks widening conversions for objects, it must be exact for primitive types.

Parameters: c the class to check

Returns: whether an instance of c would be an instance of this class as well

Throws: NullPointerException if c is null

Since: 1.1

isEnum

public boolean isEnum()

Returns true if this class is an Enum.

Returns: true if this is an enumeration class.

Since: 1.5

isInstance

public boolean isInstance(Object o)

Discover whether an Object is an instance of this Class. Think of it as almost like o instanceof (this class).

Parameters: o the Object to check

Returns: whether o is an instance of this class

Since: 1.1

isInterface

public boolean isInterface()

Check whether this class is an interface or not. Array types are not interfaces.

Returns: whether this class is an interface or not

isLocalClass

public boolean isLocalClass()

Returns true if this object represents an local class.

Returns: true if this object represents an local class.

Since: 1.5

isMemberClass

public boolean isMemberClass()

Returns true if this object represents an member class.

Returns: true if this object represents an member class.

Since: 1.5

isPrimitive

public boolean isPrimitive()

Return whether this class is a primitive type. A primitive type class is a class representing a kind of "placeholder" for the various primitive types, or void. You can access the various primitive type classes through java.lang.Boolean.TYPE, java.lang.Integer.TYPE, etc., or through boolean.class, int.class, etc.

Returns: whether this class is a primitive type

Since: 1.1

See Also: TYPE TYPE TYPE TYPE TYPE TYPE TYPE TYPE TYPE

isSynthetic

public boolean isSynthetic()

Returns true if this class is a synthetic class, generated by the compiler.

Returns: true if this is a synthetic class.

Since: 1.5

newInstance

public T newInstance()

Get a new instance of this class by calling the no-argument constructor. The class is initialized if it has not been already. A security check may be performed, with checkMemberAccess(this, Member.PUBLIC) as well as checkPackageAccess both having to succeed.

Returns: a new instance of this class

Throws: InstantiationException if there is not a no-arg constructor for this class, including interfaces, abstract classes, arrays, primitive types, and void; or if an exception occurred during the constructor IllegalAccessException if you are not allowed to access the no-arg constructor because of scoping reasons SecurityException if the security check fails ExceptionInInitializerError if class initialization caused by this call fails with an exception

toString

public String toString()

Return the human-readable form of this Object. For an object, this is either "interface " or "class " followed by getName(), for primitive types and void it is just getName().

Returns: the human-readable form of this Object