org.springframework.graphql.data.method

Class HandlerMethod

java.lang.Object

org.springframework.graphql.data.method.HandlerMethod

Direct Known Subclasses:

InvocableHandlerMethodSupport

public class HandlerMethod
extends Object

Encapsulates information about a handler method consisting of a method and a bean. Provides convenient access to method parameters, the method return value, method annotations, etc.

The class may be created with a bean instance or with a bean name (e.g. lazy-init bean, prototype bean). Use createWithResolvedBean() to obtain a HandlerMethod instance with a bean instance resolved through the associated BeanFactory.

Since:

1.0.0

Author:

Rossen Stoyanchev

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	HandlerMethod.HandlerMethodParameter A MethodParameter with HandlerMethod-specific behavior.

Field Summary

Fields

Modifier and Type	Field and Description
protected static Log	logger

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	HandlerMethod(HandlerMethod handlerMethod) Copy constructor for use from subclasses that accept more arguments.
	HandlerMethod(Object bean, Method method) Constructor with a handler instance and a method.
	HandlerMethod(String beanName, BeanFactory beanFactory, Method method) Constructor with a bean name for the handler along with a BeanFactory to allow resolving the handler instance later.

Method Summary

Modifier and Type	Method and Description
protected void	assertTargetBean(Method method, Object targetBean, Object[] args) Assert that the target bean class is an instance of the class where the given method is declared.
HandlerMethod	createWithResolvedBean() If the provided instance contains a bean name rather than an object instance, the bean name is resolved before a HandlerMethod is created and returned.
boolean	equals(Object other)
protected static Object	findProvidedArgument(MethodParameter parameter, Object... providedArgs)
protected static String	formatArgumentError(MethodParameter param, String message)
protected String	formatInvokeError(String text, Object[] args)
Object	getBean() Return the bean for this handler method.
Class<?>	getBeanType() This method returns the type of the handler for this handler method.
protected Method	getBridgedMethod() If the bean method is a bridge method, this method returns the bridged (user-defined) method.
Method	getMethod() Return the method for this handler method.
<A extends Annotation> A	getMethodAnnotation(Class<A> annotationType) Return a single annotation on the underlying method traversing its super methods if no annotation can be found on the given method itself.
MethodParameter[]	getMethodParameters() Return the method parameters for this handler method.
MethodParameter	getReturnType() Return the HandlerMethod return type.
MethodParameter	getReturnValueType(Object returnValue) Return the actual return value type.
String	getShortLogMessage() Return a short representation of this handler method for log message purposes.
int	hashCode()
<A extends Annotation> boolean	hasMethodAnnotation(Class<A> annotationType) Return whether the parameter is declared with the given annotation type.
boolean	isVoid() Return true if the method return type is void, false otherwise.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

logger

protected static final Log logger

Constructor Detail

HandlerMethod

public HandlerMethod(Object bean,
                     Method method)

Constructor with a handler instance and a method.

HandlerMethod

public HandlerMethod(String beanName,
                     BeanFactory beanFactory,
                     Method method)

Constructor with a bean name for the handler along with a BeanFactory to allow resolving the handler instance later.

HandlerMethod

protected HandlerMethod(HandlerMethod handlerMethod)

Copy constructor for use from subclasses that accept more arguments.

Method Detail

getBean

public Object getBean()

Return the bean for this handler method.

getMethod

public Method getMethod()

Return the method for this handler method.

getBeanType

public Class<?> getBeanType()

This method returns the type of the handler for this handler method.

Note that if the bean type is a CGLIB-generated class, the original user-defined class is returned.

getBridgedMethod

protected Method getBridgedMethod()

If the bean method is a bridge method, this method returns the bridged (user-defined) method. Otherwise it returns the same method as getMethod().

getMethodParameters

public MethodParameter[] getMethodParameters()

Return the method parameters for this handler method.

getReturnType

public MethodParameter getReturnType()

Return the HandlerMethod return type.

getReturnValueType

public MethodParameter getReturnValueType(@Nullable
                                          Object returnValue)

Return the actual return value type.

isVoid

public boolean isVoid()

Return true if the method return type is void, false otherwise.

getMethodAnnotation

@Nullable
public <A extends Annotation> A getMethodAnnotation(Class<A> annotationType)

Return a single annotation on the underlying method traversing its super methods if no annotation can be found on the given method itself.

Also supports merged composed annotations with attribute overrides as of Spring Framework 4.3.

Parameters:

annotationType - the type of annotation to introspect the method for

Returns:

the annotation, or null if none found

See Also:

AnnotatedElementUtils.findMergedAnnotation(java.lang.reflect.AnnotatedElement, java.lang.Class<A>)

hasMethodAnnotation

public <A extends Annotation> boolean hasMethodAnnotation(Class<A> annotationType)

Return whether the parameter is declared with the given annotation type.

Parameters:

annotationType - the annotation type to look for

See Also:

AnnotatedElementUtils.hasAnnotation(java.lang.reflect.AnnotatedElement, java.lang.Class<? extends java.lang.annotation.Annotation>)

createWithResolvedBean

public HandlerMethod createWithResolvedBean()

If the provided instance contains a bean name rather than an object instance, the bean name is resolved before a HandlerMethod is created and returned.

getShortLogMessage

public String getShortLogMessage()

Return a short representation of this handler method for log message purposes.

equals

public boolean equals(@Nullable
                      Object other)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object

findProvidedArgument

@Nullable
protected static Object findProvidedArgument(MethodParameter parameter,
                                                       @Nullable
                                                       Object... providedArgs)

formatArgumentError

protected static String formatArgumentError(MethodParameter param,
                                            String message)

assertTargetBean

protected void assertTargetBean(Method method,
                                Object targetBean,
                                Object[] args)

Assert that the target bean class is an instance of the class where the given method is declared. In some cases the actual endpoint instance at request- processing time may be a JDK dynamic proxy (lazy initialization, prototype beans, and others). Endpoint classes that require proxying should prefer class-based proxy mechanisms.

formatInvokeError

protected String formatInvokeError(String text,
                                   Object[] args)