org.jtransfo.internal.ToHelper Maven / Gradle / Ivy
/*
* This file is part of jTransfo, a library for converting to and from transfer objects.
* Copyright (c) PROGS bvba, Belgium
*
* The program is available in open source according to the Apache License, Version 2.0.
* For full licensing details, see LICENSE.txt in the project root.
*/
package org.jtransfo.internal;
import org.jtransfo.ClassReplacer;
import org.jtransfo.DomainClass;
import org.jtransfo.DomainClassDelegate;
import org.jtransfo.JTransfoException;
import java.util.List;
/**
* Helper for working with transfer objects.
*/
public class ToHelper {
private ReflectionHelper reflectionHelper = new ReflectionHelper();
private ClassReplacer classReplacer = c -> c;
/**
* Set the {@link ClassReplacer} which combines the configured class replacers for this jTransfo instance.
*
* @param classReplacer class replacer
*/
public void setClassReplacer(ClassReplacer classReplacer) {
this.classReplacer = classReplacer;
}
/**
* Is the given object a transfer object?
*
* True when there is a {@link DomainClass} annotation on the class.
*
*
* @param object object to test
* @return true when object is a transfer object
*/
public boolean isTo(Object object) {
return isToClass(object.getClass());
}
/**
* Is the given class a transfer object class?
*
* True when there is a {@link DomainClass} annotation on the class.
*
*
* @param toClass object class to test
* @return true when object is a transfer object
*/
public boolean isToClass(Class toClass) {
List domainClasses = reflectionHelper.getAnnotationWithMeta(toClass, DomainClass.class);
return 0 != domainClasses.size();
}
/**
* Get domain class for transfer object.
*
* @param toClass transfer object class
* @return domain class as annotated on class
*/
public Class getDomainClass(Class toClass) {
Class declaredClass = getDeclaredDomainClass(toClass);
return classReplacer.replaceClass(declaredClass);
}
private Class getDeclaredDomainClass(Class toClass) {
List domainClasses = reflectionHelper.getAnnotationWithMeta(toClass, DomainClass.class);
if (0 == domainClasses.size()) {
throw new JTransfoException("Transfer object of type " + toClass.getName() +
" not annotated with DomainClass.");
}
if (1 < domainClasses.size()) {
throw new JTransfoException("Transfer object of type " + toClass.getName() +
" DomainClass is ambiguous, check your meta-annotations.");
}
DomainClass domainClass = domainClasses.get(0);
if (DomainClass.DefaultClass.class != domainClass.domainClass()) {
return domainClass.domainClass();
}
if (DomainClass.DEFAULT_NAME.equals(domainClass.value())) {
throw new JTransfoException("Transfer object of type " + toClass.getName() +
" DomainClass annotation does not specify class.");
}
try {
return reflectionHelper.loadClass(domainClass.value());
} catch (ClassNotFoundException cnfe) {
throw new JTransfoException("Transfer object of type " + toClass.getName() +
" DomainClass " + domainClass.value() + " not found.", cnfe);
}
}
/**
* Get the correct transfer object type for the given domain object.
*
* This searches the DomainClassDelegates (if present) to see of there is a better matching transfer object than
* the one given as parameter.
*
*
* @param toType base transfer object type
* @param domainObject domain object (instance)
* @return proper transfer object type to use
*/
public Class getToSubType(Class toType, Object domainObject) {
DomainClassDelegate domainClassDelegate = toType.getAnnotation(DomainClassDelegate.class);
if (null != domainClassDelegate) {
for (Class delegate : domainClassDelegate.delegates()) {
Class delegateDomain = getDomainClass(delegate);
if (delegateDomain.isInstance(domainObject)) {
toType = delegate;
}
}
}
return toType;
}
}