org.graalvm.nativeimage

Class MissingReflectionRegistrationError

java.lang.Object

java.lang.Throwable

java.lang.Error

org.graalvm.nativeimage.MissingReflectionRegistrationError

All Implemented Interfaces:

Serializable

public final class MissingReflectionRegistrationError
extends Error

This exception is thrown when a reflective query (such as Class.getMethod(String, Class[])) tries to access an element that was not registered for reflection in the program. When an element is not registered, the exception will be thrown both for elements that exist and elements that do not exist on the given classpath.

The purpose of this exception is to easily discover unregistered elements and to assure that all reflective operations for registered elements have the expected behaviour.

We distinguish between two types of reflective queries: bulk queries and individual queries.

1. Bulk queries are methods like Class.getFields() which return a complete list of corresponding elements. Those queries need to be explicitly registered for reflection in order to be called. If that is not the case, a MissingReflectionRegistrationError will be thrown.
2. Individual queries are methods like Class.getField(String) which return a single element. Those queries will succeed (or throw the expected ReflectiveOperationException if either the element was individually registered for reflection, or the corresponding bulk query was registered for reflection. If that is not the case, a MissingReflectionRegistrationError will be thrown. Some individual queries, like Class.forName(String), do not have a corresponding bulk query and as such need their arguments to be individually registered for reflection in order to behave correctly.

Examples:

Registration: "queryAllDeclaredMethods": true
declaringClass.getDeclaredMethods() will succeed.
declaringClass.getDeclaredMethod("existingMethod") will return the expected method.
declaringClass.getDeclaredMethod("nonexistentMethod") will throw a NoSuchMethodException.

Registration: "fields": [{"name": "registeredField"}, {"name": "registeredNonexistentField"}]
declaringClass.getDeclaredFields() will throw a MissingReflectionRegistrationError.
declaringClass.getField("registeredField") will return the expected field.
declaringClass.getField("registeredNonexistentField") will throw a NoSuchFieldException.
declaringClass.getField("unregisteredField") will throw a MissingReflectionRegistrationError.
declaringClass.getField("unregisteredNonexistentField") will throw a MissingReflectionRegistrationError.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
MissingReflectionRegistrationError(String message, Class<?> elementType, Class<?> declaringClass, String elementName, Class<?>[] parameterTypes)

Method Summary

Modifier and Type	Method and Description
Class<?>	getDeclaringClass()
String	getElementName()
Class<?>	getElementType()
Class<?>[]	getParameterTypes()

Methods inherited from class java.lang.Throwable

addSuppressed, fillInStackTrace, getCause, getLocalizedMessage, getMessage, getStackTrace, getSuppressed, initCause, printStackTrace, printStackTrace, printStackTrace, setStackTrace, toString

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

MissingReflectionRegistrationError

public MissingReflectionRegistrationError(String message,
                                          Class<?> elementType,
                                          Class<?> declaringClass,
                                          String elementName,
                                          Class<?>[] parameterTypes)

Method Detail

getElementType

public Class<?> getElementType()

Returns:

The type of the element trying to be queried (Class, Method, Field or Constructor), or null if the query is a bulk query (like Class.getMethods()).

getDeclaringClass

public Class<?> getDeclaringClass()

Returns:

The class on which the missing query was tried, or null on static queries (e.g. Class.forName(String)).

getElementName

public String getElementName()

Returns:

The name of the queried element, or bulk query method (e.g. "getMethods").

getParameterTypes

public Class<?>[] getParameterTypes()

Returns:

The parameter types passed to the query, or null if the query doesn't take parameter types as argument.