Decimal128WithSpringDataMongoDB.java

/*
 * Copyright 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 com.example;

import lombok.Data;

import java.math.BigDecimal;
import java.util.Arrays;

import javax.annotation.PostConstruct;

import org.bson.types.Decimal128;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.core.convert.converter.Converter;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.convert.CustomConversions;
import org.springframework.data.mongodb.core.mapping.Document;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.core.query.Update;

import com.mongodb.DBObject;

/**
 * Shows Mongo 3.4 {@link Decimal128} use with Spring Data MongoDB
 * 
 * @author Mark Paluch
 */
@SpringBootApplication
public class Decimal128WithSpringDataMongoDB {

	@Bean
	public CustomConversions customConversions() {

		return new CustomConversions(
				Arrays.asList(BigDecimalToDecimal128Converter.INSTANCE, Decimal128ToBigDecimalConverter.INSTANCE)) {

			// Required for converter use (BigDecimal <-> Decimal128)
			@Override
			public Class<?> getCustomWriteTarget(Class<?> sourceType) {

				if (sourceType == BigDecimal.class) {
					return Decimal128.class;
				}

				return super.getCustomWriteTarget(sourceType);
			}

			// Required for native Decimal128 use
			@Override
			public boolean isSimpleType(Class<?> type) {
				return type == Decimal128.class || super.isSimpleType(type);
			}
		};
	}

	public static void main(String[] args) {
		SpringApplication.run(Decimal128WithSpringDataMongoDB.class, args);
	}

	@Autowired MongoTemplate mongoTemplate;

	@PostConstruct
	private void postConstruct() {

		mongoTemplate.dropCollection("person");

		Person person = new Person();
		person.setDecimal(new BigDecimal("123.456"));
		person.setDecimal128(new Decimal128(new BigDecimal("123.456")));

		mongoTemplate.save(person);

		mongoTemplate.updateFirst(new Query(), new Update().inc("decimal", 5), Person.class);

		Person loaded = mongoTemplate.findById(person.getId(), Person.class);
		DBObject dbObject = mongoTemplate.findById(person.getId(), DBObject.class, "person");

		System.out.println(loaded.getDecimal());
		System.out.println(loaded.getDecimal128());

		System.out.println((Decimal128) dbObject.get("decimal"));
		System.out.println((Decimal128) dbObject.get("decimal128"));
	}

	@Document
	@Data
	static class Person {
		String id;
		BigDecimal decimal;
		Decimal128 decimal128;
	}

	private static enum BigDecimalToDecimal128Converter implements Converter<BigDecimal, Decimal128> {
		INSTANCE;

		@Override
		public Decimal128 convert(BigDecimal bigDecimal) {
			return new Decimal128(bigDecimal);
		}
	}

	private static enum Decimal128ToBigDecimalConverter implements Converter<Decimal128, BigDecimal> {
		INSTANCE;

		@Override
		public BigDecimal convert(Decimal128 decimal128) {
			return decimal128.bigDecimalValue();
		}
	}
}