Method

Method

java.lang.reflect

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Java 1.1

This class represents a method. Instances of Method are obtained by calling the getMethod( ) and related methods of java.lang.Class . Method implements the Member interface, so you can use the methods of that interface to obtain the method name , modifiers, and declaring class. In addition, getreturnType( ) , getParameterTypes( ) , and getExceptionTypes( ) also return important information about the represented method.

Perhaps most importantly, the invoke( ) method allows the method represented by the Method object to be invoked with a specified array of argument values. If any of the arguments are of primitive types, they must be converted to their corresponding wrapper object types in order to be passed to invoke( ) . If the represented method is an instance method (i.e., if it is not static ), the instance on which it should be invoked must also be passed to invoke( ) . The return value of the represented method is returned by invoke( ) . If the return value is a primitive value, it is first converted to the corresponding wrapper type. If the invoked method causes an exception, the Throwable object it throws is wrapped within the InvocationTargetException that is thrown by invoke( ) .

In Java 5.0, Method implements GenericDeclaration to support reflection on the type variables defined by generic methods and AnnotatedElement to support reflection on method annotations. Additionally, getParameterAnnotations( ) supports reflection on method parameter annotations. The new methods getGenericReturnType( ) , getGenericParameterTypes( ) , and getGenericExceptionTypes( ) support reflection on generic method signatures. Finally, the new isVarArgs( ) method returns true if the method was declared using Java 5.0 varargs syntax.

Figure 10-98. java.lang.reflect.Method

 public final class  Method  extends AccessibleObject implements GenericDeclaration, Member {  // No Constructor   // Public Instance Methods   5.0  public Object  getDefaultValue  ( );        public Class<?>[ ]  getExceptionTypes  ( );  5.0  public Type[ ]  getGenericExceptionTypes  ( );  5.0  public Type[ ]  getGenericParameterTypes  ( );  5.0  public Type  getGenericReturnType  ( );  5.0  public java.lang.annotation.Annotation[ ][ ]  getParameterAnnotations  ( );        public Class<?>[ ]  getParameterTypes  ( );        public Class<?>  getReturnType  ( );        public Object  invoke  (Object  obj  , Object...  args  )  throws IllegalAccessException, IllegalArgumentException, InvocationTargetException;  5.0  public boolean  isBridge  ( );  5.0  public boolean  isVarArgs  ( );  5.0  public String  toGenericString  ( );  // Methods Implementing GenericDeclaration   5.0  public TypeVariable<Method>[ ]  getTypeParameters  ( );  // Methods Implementing Member  public Class<?>  getDeclaringClass  ( );        public int  getModifiers  ( );        public String  getName  ( );  5.0  public boolean  isSynthetic  ( );  // Public Methods Overriding AccessibleObject   5.0  public <T extends java.lang.annotation.Annotation> T  getAnnotation  (Class<T>  annotationClass  );  5.0  public java.lang.annotation.Annotation[ ]  getDeclaredAnnotations  ( );  // Public Methods Overriding Object  public boolean  equals  (Object  obj  );        public int  hashCode  ( );        public String  toString  ( );   } 

Passed To

java.lang.annotation.AnnotationTypeMismatchException.AnnotationTypeMismatchException( ) , InvocationHandler.invoke( )

Returned By

Class.{getDeclaredMethod( ) , geTDeclaredMethods( ) , getEnclosingMethod( ) , getMethod( ) , getMethods( )} , java.lang.annotation.AnnotationTypeMismatchException.element( )