AbstractPersistentProperty.java

/*
 * Copyright 2011-2017 the original author or authors.
 *
 * 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.springframework.data.mapping.model;

import lombok.AccessLevel;
import lombok.Getter;

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Map;
import java.util.Optional;
import java.util.regex.Pattern;

import org.springframework.data.annotation.Reference;
import org.springframework.data.mapping.Association;
import org.springframework.data.mapping.PersistentEntity;
import org.springframework.data.mapping.PersistentProperty;
import org.springframework.data.mapping.PropertyPath;
import org.springframework.data.util.Lazy;
import org.springframework.data.util.TypeInformation;
import org.springframework.util.Assert;
import org.springframework.util.ReflectionUtils;

/**
 * Simple impementation of {@link PersistentProperty}.
 * 
 * @author Jon Brisbin
 * @author Oliver Gierke
 * @author Christoph Strobl
 */
public abstract class AbstractPersistentProperty<P extends PersistentProperty<P>> implements PersistentProperty<P> {

	private static final Field CAUSE_FIELD;

	static {
		CAUSE_FIELD = ReflectionUtils.findField(Throwable.class, "cause");
	}

	private final String name;
	private final TypeInformation<?> information;
	private final Class<?> rawType;
	private final Lazy<Optional<Association<P>>> association;
	private final @Getter PersistentEntity<?, P> owner;
	private final @Getter(AccessLevel.PROTECTED) Property property;
	private final Lazy<Integer> hashCode;
	private final Lazy<Boolean> usePropertyAccess;
	private final Lazy<Optional<? extends TypeInformation<?>>> entityTypeInformation;

	public AbstractPersistentProperty(Property property, PersistentEntity<?, P> owner,
			SimpleTypeHolder simpleTypeHolder) {

		Assert.notNull(simpleTypeHolder, "SimpleTypeHolder must not be null!");
		Assert.notNull(owner, "Owner entity must not be null!");

		this.name = property.getName();
		this.rawType = property.getType();
		this.information = PropertyPath.from(Pattern.quote(property.getName()), owner.getTypeInformation())
				.getTypeInformation();
		this.property = property;
		this.association = Lazy.of(() -> isAssociation() ? Optional.of(createAssociation()) : Optional.empty());
		this.owner = owner;

		this.hashCode = Lazy.of(property::hashCode);
		this.usePropertyAccess = Lazy
				.of(() -> owner.getType().isInterface() || getField().map(it -> it.equals(CAUSE_FIELD)).orElse(false));
		this.entityTypeInformation = Lazy.of(() -> Optional.ofNullable(information.getActualType())//
				.filter(it -> !simpleTypeHolder.isSimpleType(it.getType()))//
				.filter(it -> !it.isCollectionLike())//
				.filter(it -> !it.isMap()));
	}

	protected abstract Association<P> createAssociation();

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getName()
	 */
	@Override
	public String getName() {
		return name;
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getType()
	 */
	@Override
	public Class<?> getType() {
		return information.getType();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getRawType()
	 */
	@Override
	public Class<?> getRawType() {
		return this.rawType;
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getTypeInformation()
	 */
	@Override
	public TypeInformation<?> getTypeInformation() {
		return information;
	}

	/* 
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getPersistentEntityType()
	 */
	@Override
	public Iterable<? extends TypeInformation<?>> getPersistentEntityType() {

		if (!isEntity()) {
			return Collections.emptySet();
		}

		return entityTypeInformation.get()//
				.map(it -> Collections.singleton(it))//
				.orElseGet(() -> Collections.emptySet());
	}

	/* 
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getGetter()
	 */
	@Override
	public Optional<Method> getGetter() {
		return property.getGetter();
	}

	/* 
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getSetter()
	 */
	@Override
	public Optional<Method> getSetter() {
		return property.getSetter();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getField()
	 */
	@Override
	public Optional<Field> getField() {
		return property.getField();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getSpelExpression()
	 */
	@Override
	public Optional<String> getSpelExpression() {
		return Optional.empty();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#isTransient()
	 */
	@Override
	public boolean isTransient() {
		return false;
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#isWritable()
	 */
	@Override
	public boolean isWritable() {
		return !isTransient();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#isAssociation()
	 */
	@Override
	public boolean isAssociation() {
		return isAnnotationPresent(Reference.class);
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getAssociation()
	 */
	@Override
	public Optional<Association<P>> getAssociation() {
		return association.get();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#isCollectionLike()
	 */
	@Override
	public boolean isCollectionLike() {
		return information.isCollectionLike();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#isMap()
	 */
	@Override
	public boolean isMap() {
		return Map.class.isAssignableFrom(getType());
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#isArray()
	 */
	@Override
	public boolean isArray() {
		return getType().isArray();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#isEntity()
	 */
	@Override
	public boolean isEntity() {
		return !isTransient() && entityTypeInformation.get().isPresent();
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getComponentType()
	 */
	@Override
	public Optional<Class<?>> getComponentType() {

		if (!isMap() && !isCollectionLike()) {
			return Optional.empty();
		}

		return Optional.of(information.getRequiredComponentType().getType());
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getMapValueType()
	 */
	@Override
	public Optional<Class<?>> getMapValueType() {
		return isMap() ? information.getMapValueType().map(TypeInformation::getType) : Optional.empty();
	}

	/* 
	 * (non-Javadoc)
	 * @see org.springframework.data.mapping.PersistentProperty#getActualType()
	 */
	@Override
	public Class<?> getActualType() {
		return information.getActualType().getType();
	}

	/* 
	 * (non-Javadoc)
	 * @see org.springframework.data.mongodb.core.mapping.MongoPersistentProperty#usePropertyAccess()
	 */
	public boolean usePropertyAccess() {
		return usePropertyAccess.get();
	}

	/* 
	 * (non-Javadoc)
	 * @see java.lang.Object#equals(java.lang.Object)
	 */
	@Override
	public boolean equals(Object obj) {

		if (this == obj) {
			return true;
		}

		if (!(obj instanceof AbstractPersistentProperty)) {
			return false;
		}

		AbstractPersistentProperty<?> that = (AbstractPersistentProperty<?>) obj;

		return this.property.equals(that.property);
	}

	/* 
	 * (non-Javadoc)
	 * @see java.lang.Object#hashCode()
	 */
	@Override
	public int hashCode() {
		return this.hashCode.get();
	}

	/* 
	 * (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		return property.toString();
	}
}