ReflectiveMetaProperty.java
/*
* Copyright 2001-present 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.lang.annotation.Annotation;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
import org.joda.beans.Bean;
import org.joda.beans.ImmutableBean;
import org.joda.beans.MetaBean;
import org.joda.beans.PropertyStyle;
import org.joda.beans.impl.BasicMetaProperty;
/**
* A meta-property implemented using a {@code PropertyDescriptor}.
* <p>
* The property descriptor class is part of the JDK JavaBean standard.
* It provides access to get and set a property on a bean.
* <p>
* 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 <P> the type of the property content
*/
final class ReflectiveMetaProperty<P> extends BasicMetaProperty<P> {
/** The meta-bean. */
private volatile MetaBean metaBean;
/** The declaring type. */
private final Class<?> declaringType;
/** The type of the property. */
private final Class<P> propertyType;
/** The getter. */
private final Method getMethod;
/** The setter. */
private final Method setMethod;
/**
* Constructor using {@code PropertyDescriptor} to find the get and set methods.
*
* @param metaBean the meta-bean
* @param beanType the bean type, not null
* @param propertyName the property name, not empty
*/
@SuppressWarnings({"unchecked", "null"})
ReflectiveMetaProperty(MetaBean metaBean, Class<? extends Bean> beanType, String propertyName) {
super(propertyName);
String getterName = "get" + propertyName.substring(0, 1).toUpperCase(Locale.ENGLISH) + propertyName.substring(1);
String isserName = "is" + propertyName.substring(0, 1).toUpperCase(Locale.ENGLISH) + propertyName.substring(1);
Method getMethod = findGetMethod(beanType, getterName);
Method isMethod = findGetMethod(beanType, isserName);
if (getMethod == null && isMethod == null) {
throw new IllegalArgumentException(
"Unable to find property getter: " + beanType.getSimpleName() + "." + getterName + "()");
}
getMethod = isMethod != null ? isMethod : getMethod;
Method setMethod = null;
if (!ImmutableBean.class.isAssignableFrom(beanType)) {
String setterName = "set" + propertyName.substring(0, 1).toUpperCase(Locale.ENGLISH) + propertyName.substring(1);
setMethod = findSetMethod(beanType, setterName, getMethod.getReturnType());
if (setMethod == null) {
throw new IllegalArgumentException(
"Unable to find property setter: " + beanType.getSimpleName() + "." + setterName + "()");
}
}
this.metaBean = metaBean;
this.declaringType = (getMethod != null ? getMethod.getDeclaringClass() : setMethod.getDeclaringClass());
this.propertyType = (Class<P>) getMethod.getReturnType();
this.getMethod = getMethod;
this.setMethod = setMethod;
}
// finds a method on class or public method on super-type
private static Method findGetMethod(Class<? extends Bean> beanType, String getterName) {
try {
return beanType.getDeclaredMethod(getterName);
} catch (NoSuchMethodException ex) {
try {
return beanType.getMethod(getterName);
} catch (NoSuchMethodException ex2) {
return null;
}
}
}
// finds a method on class or public method on super-type
private static Method findSetMethod(Class<? extends Bean> beanType, String setterName, Class<?> fieldType) {
try {
return beanType.getDeclaredMethod(setterName, fieldType);
} catch (NoSuchMethodException ex) {
Method[] methods = beanType.getMethods();
List<Method> potential = new ArrayList<>();
for (Method method : methods) {
if (method.getName().equals(setterName) && method.getParameterTypes().length == 1) {
potential.add(method);
}
}
if (potential.size() == 1) {
return potential.get(0);
}
for (Method method : potential) {
if (method.getParameterTypes()[0].equals(fieldType)) {
return method;
}
}
return null;
}
}
/**
* 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 MetaBean metaBean() {
return metaBean;
}
@Override
public Class<?> declaringType() {
return declaringType;
}
@Override
public Class<P> propertyType() {
return propertyType;
}
@Override
public Type propertyGenericType() {
if (getMethod != null) {
return getMethod.getGenericReturnType();
}
return setMethod.getGenericParameterTypes()[0];
}
@Override
public PropertyStyle style() {
return (getMethod == null ? PropertyStyle.WRITE_ONLY :
(setMethod == null ? PropertyStyle.READ_ONLY : PropertyStyle.READ_WRITE));
}
@Override
public List<Annotation> annotations() {
if (getMethod != null) {
return Arrays.asList(getMethod.getDeclaredAnnotations());
}
return Arrays.asList(setMethod.getDeclaredAnnotations());
}
//-----------------------------------------------------------------------
@Override
@SuppressWarnings("unchecked")
public P get(Bean bean) {
if (style().isReadable() == false) {
throw new UnsupportedOperationException("Property cannot be read: " + name());
}
try {
return (P) getMethod.invoke(bean, (Object[]) null);
} catch (IllegalArgumentException | 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);
}
}
@SuppressWarnings("null")
@Override
public void set(Bean bean, Object value) {
if (style().isWritable() == false) {
throw new UnsupportedOperationException("Property cannot be written: " + name());
}
try {
setMethod.invoke(bean, value);
} catch (IllegalArgumentException ex) {
if (value == null && setMethod.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);
}
}
}