org.joda.beans.impl.reflection.ReflectiveMetaProperty Maven / Gradle / Ivy
/*
* Copyright 2001-2014 Stephen Colebourne
*
* 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 org.joda.beans.impl.reflection;
import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.lang.annotation.Annotation;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.List;
import org.joda.beans.Bean;
import org.joda.beans.MetaBean;
import org.joda.beans.Property;
import org.joda.beans.PropertyStyle;
import org.joda.beans.impl.BasicMetaProperty;
import org.joda.beans.impl.BasicProperty;
/**
* A meta-property implemented using a {@code PropertyDescriptor}.
*
* The property descriptor class is part of the JDK JavaBean standard.
* It provides access to get and set a property on a bean.
*
* Instances of this class should be declared as a static constant on the bean,
* one for each property, followed by a {@code ReflectiveMetaBean} declaration.
*
* @param
the type of the property content
* @author Stephen Colebourne
*/
public final class ReflectiveMetaProperty
extends BasicMetaProperty
{
/** The meta-bean. */
private volatile MetaBean metaBean;
/** The declaring type. */
private final Class declaringType;
/** The type of the property. */
private final Class
propertyType;
/** The read method. */
private final Method readMethod;
/** The write method. */
private final Method writeMethod;
/**
* Factory to create a meta-property avoiding duplicate generics.
*
* @param
the property type
* @param beanType the bean type, not null
* @param propertyName the property name, not empty
* @return the property, not null
*/
public static
ReflectiveMetaProperty
of(Class beanType, String propertyName) {
return new ReflectiveMetaProperty
(beanType, propertyName);
}
/**
* Constructor using {@code PropertyDescriptor} to find the get and set methods.
*
* @param beanType the bean type, not null
* @param propertyName the property name, not empty
*/
@SuppressWarnings("unchecked")
private ReflectiveMetaProperty(Class beanType, String propertyName) {
super(propertyName);
PropertyDescriptor descriptor;
try {
descriptor = new PropertyDescriptor(propertyName, beanType);
} catch (IntrospectionException ex) {
throw new NoSuchFieldError("Invalid property: " + propertyName + ": " + ex.getMessage());
}
Method readMethod = descriptor.getReadMethod();
Method writeMethod = descriptor.getWriteMethod();
if (readMethod == null && writeMethod == null) {
throw new NoSuchFieldError("Invalid property: " + propertyName + ": Both read and write methods are missing");
}
this.declaringType = (readMethod != null ? readMethod.getDeclaringClass() : writeMethod.getDeclaringClass());
this.propertyType = (Class
) descriptor.getPropertyType();
this.readMethod = readMethod;
this.writeMethod = writeMethod;
}
/**
* Sets the meta-bean, necessary due to ordering restrictions during loading.
* @param metaBean the meta-bean, not null
*/
void setMetaBean(MetaBean metaBean) {
this.metaBean = metaBean;
}
//-----------------------------------------------------------------------
@Override
public Property
createProperty(Bean bean) {
return BasicProperty.of(bean, this);
}
@Override
public MetaBean metaBean() {
return metaBean;
}
@Override
public Class declaringType() {
return declaringType;
}
@Override
public Class
propertyType() {
return propertyType;
}
@Override
public Type propertyGenericType() {
if (readMethod != null) {
return readMethod.getGenericReturnType();
}
return writeMethod.getGenericParameterTypes()[0];
}
@Override
public PropertyStyle style() {
return (readMethod == null ? PropertyStyle.WRITE_ONLY :
(writeMethod == null ? PropertyStyle.READ_ONLY : PropertyStyle.READ_WRITE));
}
@Override
public List annotations() {
if (readMethod != null) {
return Arrays.asList(readMethod.getDeclaredAnnotations());
}
return Arrays.asList(writeMethod.getDeclaredAnnotations());
}
//-----------------------------------------------------------------------
@Override
@SuppressWarnings("unchecked")
public P get(Bean bean) {
if (style().isReadable() == false) {
throw new UnsupportedOperationException("Property cannot be read: " + name());
}
try {
return (P) readMethod.invoke(bean, (Object[]) null);
} catch (IllegalArgumentException ex) {
throw new UnsupportedOperationException("Property cannot be read: " + name(), ex);
} catch (IllegalAccessException ex) {
throw new UnsupportedOperationException("Property cannot be read: " + name(), ex);
} catch (InvocationTargetException ex) {
if (ex.getCause() instanceof RuntimeException) {
throw (RuntimeException) ex.getCause();
}
throw new RuntimeException(ex);
}
}
@Override
public void set(Bean bean, Object value) {
if (style().isWritable() == false) {
throw new UnsupportedOperationException("Property cannot be written: " + name());
}
try {
writeMethod.invoke(bean, value);
} catch (IllegalArgumentException ex) {
if (value == null && writeMethod.getParameterTypes()[0].isPrimitive()) {
throw new NullPointerException("Property cannot be written: " + name() + ": Cannot store null in primitive");
}
if (propertyType.isInstance(value) == false) {
throw new ClassCastException("Property cannot be written: " + name() + ": Invalid type: " + value.getClass().getName());
}
throw new UnsupportedOperationException("Property cannot be written: " + name(), ex);
} catch (IllegalAccessException ex) {
throw new UnsupportedOperationException("Property cannot be written: " + name(), ex);
} catch (InvocationTargetException ex) {
if (ex.getCause() instanceof RuntimeException) {
throw (RuntimeException) ex.getCause();
}
throw new RuntimeException(ex);
}
}
}