package com.airhacks.enhydrator.out;
/*
* #%L
* enhydrator
* %%
* Copyright (C) 2014 Adam Bien
* %%
* 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.
* #L%
*/
import com.airhacks.enhydrator.in.Row;
import java.lang.reflect.Field;
import java.lang.reflect.ParameterizedType;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.StringJoiner;
import java.util.function.Consumer;
import java.util.stream.Collectors;
import javafx.util.Pair;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlTransient;
/**
*
* @author airhacks.com
*/
@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElement(name = "pojo-sink")
public class PojoSink extends Sink {
private static final String DEFAULT_NAME = "pojo";
@XmlTransient
private Class target;
@XmlTransient
private Class childrenType;
@XmlTransient
private Consumer<Object> consumer;
@XmlTransient
private String childrenFieldName = null;
@XmlTransient
private final Consumer<Map<String, Object>> devNullConsumer;
@XmlTransient
private Map<String, Object> unmappedFields;
public PojoSink(Class target, Consumer<Object> consumer, Consumer<Map<String, Object>> devNull) {
this(DEFAULT_NAME, target, consumer, devNull);
}
public PojoSink(String sinkName, Class target, Consumer<Object> consumer, Consumer<Map<String, Object>> devNull) {
super(sinkName);
this.consumer = consumer;
this.target = target;
this.devNullConsumer = devNull;
initializeChildren();
}
void initializeChildren() {
final Pair<String, Class<? extends Object>> childInfo = getChildInfo(this.target);
if (childInfo != null) {
this.childrenFieldName = childInfo.getKey();
this.childrenType = childInfo.getValue();
}
checkConventions(this.target);
}
static void checkConventions(Class parent) {
Field[] declaredFields = parent.getDeclaredFields();
int counter = 0;
StringJoiner joiner = new StringJoiner(",");
for (Field field : declaredFields) {
final Class<?> type = field.getType();
if (type.isAssignableFrom(Collection.class)) {
joiner.add(field.getName());
counter++;
}
}
if (counter > 1) {
throw new IllegalStateException("Multiple (" + counter + ") collection fields with names " + joiner.toString() + "");
}
}
@Override
public void processRow(Row currentRow) {
this.unmappedFields = new HashMap<>();
Object targetObject = convert(this.target, currentRow);
if (currentRow.hasChildren() && this.childrenType != null) {
mapChildren(targetObject, currentRow.getChildren());
}
this.consumer.accept(targetObject);
if (!this.unmappedFields.isEmpty() && this.devNullConsumer != null) {
this.devNullConsumer.accept(unmappedFields);
}
}
Object convert(Class pojoType, Row currentRow) {
Object targetObject = newInstance(pojoType);
currentRow.getColumnValues().forEach((k, v) -> setField(targetObject, k, v));
return targetObject;
}
void mapChildren(Object parent, List<Row> children) {
List<Object> pojos = children.stream().
map(c -> convert(this.childrenType, c)).
collect(Collectors.toList());
setField(parent, this.childrenFieldName, pojos);
}
Object newInstance(Class clazz) throws IllegalStateException {
Object targetObject;
try {
targetObject = clazz.newInstance();
} catch (InstantiationException | IllegalAccessException ex) {
throw new IllegalStateException("Cannot instantiate: " + this.target.getName(), ex);
}
return targetObject;
}
public void setField(Object target, String name, Object value) {
Objects.requireNonNull(target, "Object cannot be null");
Class<? extends Object> targetClass = target.getClass();
Field field;
try {
field = targetClass.getDeclaredField(name);
} catch (NoSuchFieldException ex) {
field = getFieldAnnotatedWith(targetClass, name);
if (field == null) {
if (this.devNullConsumer != null) {
unmappedFields.put(name, value);
return;
} else {
throw new IllegalArgumentException(target.getClass() + " does not have a field with the name " + name, ex);
}
}
} catch (SecurityException ex) {
throw new IllegalStateException("Cannot access private field", ex);
}
try {
field.setAccessible(true);
field.set(target, value);
} catch (IllegalAccessException ex) {
throw new IllegalStateException("Cannot set field: " + name + " with " + value, ex);
} finally {
field.setAccessible(false);
}
}
public static Field getFieldAnnotatedWith(Class clazz, String name) {
Field[] fields = clazz.getDeclaredFields();
for (Field field : fields) {
ColumnName columnName = field.getAnnotation(ColumnName.class);
if (columnName != null) {
String customName = columnName.value();
if (customName.equals(name)) {
return field;
}
}
}
return null;
}
static Pair<String, Class<? extends Object>> getChildInfo(Class target) {
Field[] declaredFields = target.getDeclaredFields();
for (Field field : declaredFields) {
final Class<?> type = field.getType();
if (type.isAssignableFrom(Collection.class)) {
final ParameterizedType parameterizedType = (ParameterizedType) field.getGenericType();
String clazz = null;
try {
clazz = parameterizedType.getActualTypeArguments()[0].getTypeName();
return new Pair(field.getName(), Class.forName(clazz));
} catch (ClassNotFoundException ex) {
throw new IllegalStateException("Cannot find class " + clazz, ex);
}
}
}
return null;
}
}