/******************************************************************************
* Copyright (C) 2016 Yevgeny Krasik *
* *
* Licensed under the Apache License, Version 2.0 (the "License"); *
* you may not use this file except in compliance with the License. *
* You may obtain a copy of the License at *
* *
* http://www.apache.org/licenses/LICENSE-2.0 *
* *
* Unless required by applicable law or agreed to in writing, software *
* distributed under the License is distributed on an "AS IS" BASIS, *
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
* See the License for the specific language governing permissions and *
* limitations under the License. *
******************************************************************************/
package com.github.ykrasik.jaci.reflection;
import java.lang.annotation.Annotation;
/**
* Encapsulates all possible interactions with the Java reflection API - required for GWT, which doesn't support
* anything under java.lang.reflect
*
* @author Yevgeny Krasik
*/
public interface ReflectionAccessor {
/**
* Returns a {@code ReflectionMethod} object that reflects the specified
* declared method of the class or interface represented by this
* {@code Class} object. The {@code name} parameter is a
* {@code String} that specifies the simple name of the desired
* method, and the {@code parameterTypes} parameter is an array of
* {@code Class} objects that identify the method's formal parameter
* types, in declared order. If more than one method with the same
* parameter types is declared in a class, and one of these methods has a
* return type that is more specific than any of the others, that method is
* returned; otherwise one of the methods is chosen arbitrarily. If the
* name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
* is raised.
*
* <p> If this {@code Class} object represents an array type, then this
* method does not find the {@code clone()} method.
*
* @param clazz class to get declared method from
* @param name the name of the method
* @param parameterTypes the parameter array
* @return the {@code ReflectionMethod} object for the method of this class
* matching the specified name and parameters
* @throws NoSuchMethodException if a matching method is not found.
* @throws NullPointerException if {@code name} is {@code null}
* @throws SecurityException
* If a security manager, <i>s</i>, is present and any of the
* following conditions is met:
*
* <ul>
*
* <li> the caller's class loader is not the same as the
* class loader of this class and invocation of
* {@link SecurityManager#checkPermission
* s.checkPermission} method with
* {@code RuntimePermission("accessDeclaredMembers")}
* denies access to the declared method
*
* <li> the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
* </ul>
*
* @since JDK1.1
*/
ReflectionMethod getDeclaredMethod(Class<?> clazz, String name, Class<?>... parameterTypes) throws Exception;
/**
* Returns an array containing {@code ReflectionMethod} objects reflecting all the
* public methods of the class or interface represented by this {@code
* Class} object, including those declared by the class or interface and
* those inherited from superclasses and superinterfaces.
*
* <p> If this {@code Class} object represents a type that has multiple
* public methods with the same name and parameter types, but different
* return types, then the returned array has a {@code ReflectionMethod} object for
* each such method.
*
* <p> If this {@code Class} object represents a type with a class
* initialization method {@code <clinit>}, then the returned array does
* <em>not</em> have a corresponding {@code ReflectionMethod} object.
*
* <p> If this {@code Class} object represents an array type, then the
* returned array has a {@code ReflectionMethod} object for each of the public
* methods inherited by the array type from {@code Object}. It does not
* contain a {@code ReflectionMethod} object for {@code clone()}.
*
* <p> If this {@code Class} object represents an interface then the
* returned array does not contain any implicitly declared methods from
* {@code Object}. Therefore, if no methods are explicitly declared in
* this interface or any of its superinterfaces then the returned array
* has length 0. (Note that a {@code Class} object which represents a class
* always has public methods, inherited from {@code Object}.)
*
* <p> If this {@code Class} object represents a primitive type or void,
* then the returned array has length 0.
*
* <p> Static methods declared in superinterfaces of the class or interface
* represented by this {@code Class} object are not considered members of
* the class or interface.
*
* <p> The elements in the returned array are not sorted and are not in any
* particular order.
*
* @param clazz Class to get methods from
* @return the array of {@code ReflectionMethod} objects representing the
* public methods of this class
* @throws SecurityException
* If a security manager, <i>s</i>, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*
* @since JDK1.1
*/
ReflectionMethod[] getMethods(Class<?> clazz) throws SecurityException;
/**
* Returns an array of {@code Field} objects reflecting all the fields
* declared by the class or interface represented by this
* {@code Class} object. This includes public, protected, default
* (package) access, and private fields, but excludes inherited fields.
*
* <p> If this {@code Class} object represents a class or interface with no
* declared fields, then this method returns an array of length 0.
*
* <p> If this {@code Class} object represents an array type, a primitive
* type, or void, then this method returns an array of length 0.
*
* <p> The elements in the returned array are not sorted and are not in any
* particular order.
*
* @param clazz Class to get fields from
* @return the array of {@code Field} objects representing all the
* declared fields of this class
* @throws SecurityException
* If a security manager, <i>s</i>, is present and any of the
* following conditions is met:
*
* <ul>
*
* <li> the caller's class loader is not the same as the
* class loader of this class and invocation of
* {@link SecurityManager#checkPermission
* s.checkPermission} method with
* {@code RuntimePermission("accessDeclaredMembers")}
* denies access to the declared fields within this class
*
* <li> the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
* </ul>
*
* @since JDK1.1
*/
ReflectionField[] getDeclaredFields(Class<?> clazz) throws SecurityException;
/**
* Returns this element's annotation for the specified type if
* such an annotation is <em>present</em>, else null.
*
* @param <T> the type of the annotation to query for and return if present
* @param clazz Class to get annotation from
* @param annotationClass the Class object corresponding to the
* annotation type
* @return this element's annotation for the specified annotation type if
* present on this element, else null
* @throws NullPointerException if the given annotation class is null
* @since 1.5
*/
<T extends Annotation> T getAnnotation(Class<?> clazz, Class<T> annotationClass);
/**
* Creates a new instance of the class represented by this {@code Class}
* object. The class is instantiated as if by a {@code new}
* expression with an empty argument list. The class is initialized if it
* has not already been initialized.
*
* <p>Note that this method propagates any exception thrown by the
* nullary constructor, including a checked exception. Use of
* this method effectively bypasses the compile-time exception
* checking that would otherwise be performed by the compiler.
* The {@link
* java.lang.reflect.Constructor#newInstance(java.lang.Object...)
* Constructor.newInstance} method avoids this problem by wrapping
* any exception thrown by the constructor in a (checked) {@link
* java.lang.reflect.InvocationTargetException}.
*
* @param <T> class type
* @param clazz Class to instantiate
* @return a newly allocated instance of the class represented by this
* object.
* @throws IllegalAccessException if the class or its nullary
* constructor is not accessible.
* @throws InstantiationException
* if this {@code Class} represents an abstract class,
* an interface, an array class, a primitive type, or void;
* or if the class has no nullary constructor;
* or if the instantiation fails for some other reason.
* @throws ExceptionInInitializerError if the initialization
* provoked by this method fails.
* @throws SecurityException
* If a security manager, <i>s</i>, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*/
<T> T newInstance(Class<T> clazz) throws Exception;
/**
* Returns an array of {@code Class} objects reflecting all the
* classes and interfaces declared as members of the class represented by
* this {@code Class} object. This includes public, protected, default
* (package) access, and private classes and interfaces declared by the
* class, but excludes inherited classes and interfaces. This method
* returns an array of length 0 if the class declares no classes or
* interfaces as members, or if this {@code Class} object represents a
* primitive type, an array class, or void.
*
* @param clazz Class to reflect inner classes from.
* @return the array of {@code Class} objects representing all the
* declared members of this class
* @throws Exception
* If a security manager, <i>s</i>, is present and any of the
* following conditions is met:
*
* <ul>
*
* <li> the caller's class loader is not the same as the
* class loader of this class and invocation of
* {@link SecurityManager#checkPermission
* s.checkPermission} method with
* {@code RuntimePermission("accessDeclaredMembers")}
* denies access to the declared classes within this class
*
* <li> the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
* </ul>
*
* @since JDK1.1
*/
Class<?>[] getDeclaredClasses(Class<?> clazz) throws Exception;
/**
* Returns a {@code Constructor} object that reflects the specified
* constructor of the class or interface represented by this
* {@code Class} object. The {@code parameterTypes} parameter is
* an array of {@code Class} objects that identify the constructor's
* formal parameter types, in declared order.
*
* If this {@code Class} object represents an inner class
* declared in a non-static context, the formal parameter types
* include the explicit enclosing instance as the first parameter.
*
* @param clazz Class to reflect constructor from.
* @param parameterTypes the parameter array
* @param <T> Class type
* @return The {@code Constructor} object for the constructor with the
* specified parameter list
* @throws NoSuchMethodException if a matching method is not found.
* @throws Exception
* If a security manager, <i>s</i>, is present and any of the
* following conditions is met:
*
* <ul>
*
* <li> the caller's class loader is not the same as the
* class loader of this class and invocation of
* {@link SecurityManager#checkPermission
* s.checkPermission} method with
* {@code RuntimePermission("accessDeclaredMembers")}
* denies access to the declared constructor
*
* <li> the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class
*
* </ul>
*
* @since JDK1.1
*/
<T> ReflectionConstructor<T> getDeclaredConstructor(Class<T> clazz, Class<?>... parameterTypes) throws Exception;
/**
* Determines if the class or interface represented by this
* {@code Class} object is either the same as, or is a superclass or
* superinterface of, the class or interface represented by the specified
* {@code Class} parameter. It returns {@code true} if so;
* otherwise it returns {@code false}. If this {@code Class}
* object represents a primitive type, this method returns
* {@code true} if the specified {@code Class} parameter is
* exactly this {@code Class} object; otherwise it returns
* {@code false}.
*
* <p> Specifically, this method tests whether the type represented by the
* specified {@code Class} parameter can be converted to the type
* represented by this {@code Class} object via an identity conversion
* or via a widening reference conversion. See <em>The Java Language
* Specification</em>, sections 5.1.1 and 5.1.4 , for details.
*
* @param c1 the {@code Class} object to be checked
* @param c2 the {@code Class} object to be checked
* @return the {@code boolean} value indicating whether objects of the
* type {@code cls} can be assigned to objects of this class
* @since JDK1.1
*/
boolean isAssignableFrom(Class<?> c1, Class<?> c2);
}