com.badlogic.gdx.utils.reflect.Field Maven / Gradle / Ivy
/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* 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.badlogic.gdx.utils.reflect;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.Modifier;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
/** Provides information about, and access to, a single field of a class or interface.
* @author nexsoftware */
public final class Field {
private final java.lang.reflect.Field field;
Field (java.lang.reflect.Field field) {
this.field = field;
}
/** Returns the name of the field. */
public String getName () {
return field.getName();
}
/** Returns a Class object that identifies the declared type for the field. */
public Class getType () {
return field.getType();
}
/** Returns the Class object representing the class or interface that declares the field. */
public Class getDeclaringClass () {
return field.getDeclaringClass();
}
public boolean isAccessible () {
return field.isAccessible();
}
public void setAccessible (boolean accessible) {
field.setAccessible(accessible);
}
/** Return true if the field does not include any of the {@code private}, {@code protected}, or {@code public} modifiers. */
public boolean isDefaultAccess () {
return !isPrivate() && !isProtected() && !isPublic();
}
/** Return true if the field includes the {@code final} modifier. */
public boolean isFinal () {
return Modifier.isFinal(field.getModifiers());
}
/** Return true if the field includes the {@code private} modifier. */
public boolean isPrivate () {
return Modifier.isPrivate(field.getModifiers());
}
/** Return true if the field includes the {@code protected} modifier. */
public boolean isProtected () {
return Modifier.isProtected(field.getModifiers());
}
/** Return true if the field includes the {@code public} modifier. */
public boolean isPublic () {
return Modifier.isPublic(field.getModifiers());
}
/** Return true if the field includes the {@code static} modifier. */
public boolean isStatic () {
return Modifier.isStatic(field.getModifiers());
}
/** Return true if the field includes the {@code transient} modifier. */
public boolean isTransient () {
return Modifier.isTransient(field.getModifiers());
}
/** Return true if the field includes the {@code volatile} modifier. */
public boolean isVolatile () {
return Modifier.isVolatile(field.getModifiers());
}
/** Return true if the field is a synthetic field. */
public boolean isSynthetic () {
return field.isSynthetic();
}
/** If the type of the field is parameterized, returns the Class object representing the parameter type at the specified index,
* null otherwise. */
public Class getElementType (int index) {
Type genericType = field.getGenericType();
if (genericType instanceof ParameterizedType) {
Type[] actualTypes = ((ParameterizedType)genericType).getActualTypeArguments();
if (actualTypes.length - 1 >= index) {
Type actualType = actualTypes[index];
if (actualType instanceof Class)
return (Class)actualType;
else if (actualType instanceof ParameterizedType)
return (Class)((ParameterizedType)actualType).getRawType();
else if (actualType instanceof GenericArrayType) {
Type componentType = ((GenericArrayType)actualType).getGenericComponentType();
if (componentType instanceof Class) return ArrayReflection.newInstance((Class)componentType, 0).getClass();
}
}
}
return null;
}
/** Returns true if the field includes an annotation of the provided class type. */
public boolean isAnnotationPresent (Class annotationType) {
return field.isAnnotationPresent(annotationType);
}
/** Returns an array of {@link Annotation} objects reflecting all annotations declared by this field, or an empty array if
* there are none. Does not include inherited annotations. */
public Annotation[] getDeclaredAnnotations () {
java.lang.annotation.Annotation[] annotations = field.getDeclaredAnnotations();
Annotation[] result = new Annotation[annotations.length];
for (int i = 0; i < annotations.length; i++) {
result[i] = new Annotation(annotations[i]);
}
return result;
}
/** Returns an {@link Annotation} object reflecting the annotation provided, or null of this field doesn't have such an
* annotation. This is a convenience function if the caller knows already which annotation type he's looking for. */
public Annotation getDeclaredAnnotation (Class annotationType) {
java.lang.annotation.Annotation[] annotations = field.getDeclaredAnnotations();
if (annotations == null) {
return null;
}
for (java.lang.annotation.Annotation annotation : annotations) {
if (annotation.annotationType().equals(annotationType)) {
return new Annotation(annotation);
}
}
return null;
}
/** Returns the value of the field on the supplied object. */
public Object get (Object obj) throws ReflectionException {
try {
return field.get(obj);
} catch (IllegalArgumentException e) {
throw new ReflectionException("Object is not an instance of " + getDeclaringClass(), e);
} catch (IllegalAccessException e) {
throw new ReflectionException("Illegal access to field: " + getName(), e);
}
}
/** Sets the value of the field on the supplied object. */
public void set (Object obj, Object value) throws ReflectionException {
try {
field.set(obj, value);
} catch (IllegalArgumentException e) {
throw new ReflectionException("Argument not valid for field: " + getName(), e);
} catch (IllegalAccessException e) {
throw new ReflectionException("Illegal access to field: " + getName(), e);
}
}
}