DATAMONGO-1372 - Add and register Converters for java.util.Currency.

We now support conversion from currency into ISO 4217 String and back.

Original pull request: #342.

Author: christophstrobl

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/CustomConversions.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011-2015 the original author or authors.
+ * Copyright 2011-2016 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.
@@ -42,16 +42,6 @@
 import org.springframework.data.convert.ThreeTenBackPortConverters;
 import org.springframework.data.convert.WritingConverter;
 import org.springframework.data.mapping.model.SimpleTypeHolder;
-import org.springframework.data.mongodb.core.convert.MongoConverters.BigDecimalToStringConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.BigIntegerToStringConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.DBObjectToNamedMongoScriptCoverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.DBObjectToStringConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.NamedMongoScriptToDBObjectConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.StringToBigDecimalConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.StringToBigIntegerConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.StringToURLConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.TermToStringConverter;
-import org.springframework.data.mongodb.core.convert.MongoConverters.URLToStringConverter;
 import org.springframework.data.mongodb.core.mapping.MongoSimpleTypes;
 import org.springframework.data.util.CacheValue;
 import org.springframework.util.Assert;
@@ -112,16 +102,7 @@ public CustomConversions(List<?> converters) {
 		// Add user provided converters to make sure they can override the defaults
 		toRegister.addAll(converters);
 		toRegister.add(CustomToStringConverter.INSTANCE);
-		toRegister.add(BigDecimalToStringConverter.INSTANCE);
-		toRegister.add(StringToBigDecimalConverter.INSTANCE);
-		toRegister.add(BigIntegerToStringConverter.INSTANCE);
-		toRegister.add(StringToBigIntegerConverter.INSTANCE);
-		toRegister.add(URLToStringConverter.INSTANCE);
-		toRegister.add(StringToURLConverter.INSTANCE);
-		toRegister.add(DBObjectToStringConverter.INSTANCE);
-		toRegister.add(TermToStringConverter.INSTANCE);
-		toRegister.add(NamedMongoScriptToDBObjectConverter.INSTANCE);
-		toRegister.add(DBObjectToNamedMongoScriptCoverter.INSTANCE);
+		toRegister.addAll(MongoConverters.getConvertersToRegister());
 
 		toRegister.addAll(JodaTimeConverters.getConvertersToRegister());
 		toRegister.addAll(GeoConverters.getConvertersToRegister());

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/MongoConverters.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011-2015 the original author or authors.
+ * Copyright 2011-2016 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.
@@ -19,6 +19,10 @@
 import java.math.BigInteger;
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Currency;
+import java.util.List;
 
 import org.bson.types.Code;
 import org.bson.types.ObjectId;
@@ -49,6 +53,32 @@ abstract class MongoConverters {
 	 */
 	private MongoConverters() {}
 
+	/**
+	 * Returns the converters to be registered.
+	 * 
+	 * @return
+	 * @since 1.9
+	 */
+	public static Collection<Converter<?, ?>> getConvertersToRegister() {
+
+		List<Converter<?, ?>> converters = new ArrayList<Converter<?, ?>>();
+
+		converters.add(BigDecimalToStringConverter.INSTANCE);
+		converters.add(StringToBigDecimalConverter.INSTANCE);
+		converters.add(BigIntegerToStringConverter.INSTANCE);
+		converters.add(StringToBigIntegerConverter.INSTANCE);
+		converters.add(URLToStringConverter.INSTANCE);
+		converters.add(StringToURLConverter.INSTANCE);
+		converters.add(DBObjectToStringConverter.INSTANCE);
+		converters.add(TermToStringConverter.INSTANCE);
+		converters.add(NamedMongoScriptToDBObjectConverter.INSTANCE);
+		converters.add(DBObjectToNamedMongoScriptCoverter.INSTANCE);
+		converters.add(CurrencyToStringConverter.INSTANCE);
+		converters.add(StringToCurrencyConverter.INSTANCE);
+
+		return converters;
+	}
+
 	/**
 	 * Simple singleton to convert {@link ObjectId}s to their {@link String} representation.
 	 * 
@@ -228,4 +258,54 @@ public DBObject convert(NamedMongoScript source) {
 			return builder.get();
 		}
 	}
+
+	/**
+	 * {@link Converter} implementation converting {@link Currency} into its ISO 4217 {@link String} representation.
+	 * 
+	 * @author Christoph Strobl
+	 * @since 1.9
+	 */
+	@WritingConverter
+	public static enum CurrencyToStringConverter implements Converter<Currency, String> {
+		INSTANCE;
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.springframework.core.convert.converter.Converter#convert(java.lang.Object)
+		 */
+		@Override
+		public String convert(Currency source) {
+
+			if (source == null) {
+				return null;
+			}
+
+			return source.getCurrencyCode();
+		}
+	}
+
+	/**
+	 * {@link Converter} implementation converting ISO 4217 {@link String} into {@link Currency}.
+	 * 
+	 * @author Christoph Strobl
+	 * @since 1.9
+	 */
+	@ReadingConverter
+	public static enum StringToCurrencyConverter implements Converter<String, Currency> {
+		INSTANCE;
+
+		/*
+		 * (non-Javadoc)
+		 * @see org.springframework.core.convert.converter.Converter#convert(java.lang.Object)
+		 */
+		@Override
+		public Currency convert(String source) {
+
+			if (!StringUtils.hasText(source)) {
+				return null;
+			}
+
+			return Currency.getInstance(source);
+		}
+	}
 }

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/CustomConversionsUnitTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2011-2015 the original author or authors.
+ * Copyright 2011-2016 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.
@@ -24,6 +24,7 @@
 import java.text.SimpleDateFormat;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.Currency;
 import java.util.Date;
 import java.util.Locale;
 import java.util.UUID;
@@ -271,6 +272,18 @@ public void registersConverterFactoryCorrectly() {
 		assertThat(customConversions.getCustomWriteTarget(String.class, SimpleDateFormat.class), notNullValue());
 	}
 
+	/**
+	 * @see DATAMONGO-1372
+	 */
+	@Test
+	public void registersConvertersForCurrency() {
+
+		CustomConversions customConversions = new CustomConversions();
+
+		assertThat(customConversions.hasCustomWriteTarget(Currency.class), is(true));
+		assertThat(customConversions.hasCustomReadTarget(String.class, Currency.class), is(true));
+	}
+
 	private static Class<?> createProxyTypeFor(Class<?> type) {
 
 		ProxyFactory factory = new ProxyFactory();

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/MongoConvertersUnitTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2014 by the original author(s).
+ * Copyright (c) 2011-2016 by the original author(s).
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@
 import static org.junit.Assert.*;
 
 import java.math.BigDecimal;
+import java.util.Currency;
 
 import org.junit.Test;
 import org.springframework.data.geo.Box;
@@ -27,7 +28,9 @@
 import org.springframework.data.geo.Polygon;
 import org.springframework.data.geo.Shape;
 import org.springframework.data.mongodb.core.convert.MongoConverters.BigDecimalToStringConverter;
+import org.springframework.data.mongodb.core.convert.MongoConverters.CurrencyToStringConverter;
 import org.springframework.data.mongodb.core.convert.MongoConverters.StringToBigDecimalConverter;
+import org.springframework.data.mongodb.core.convert.MongoConverters.StringToCurrencyConverter;
 import org.springframework.data.mongodb.core.geo.Sphere;
 
 import com.mongodb.DBObject;
@@ -37,6 +40,7 @@
  * 
  * @author Oliver Gierke
  * @author Thomas Darimont
+ * @author Christoph Strobl
  */
 public class MongoConvertersUnitTests {
 
@@ -120,4 +124,20 @@ public void convertsPointToListAndBackCorrectly() {
 
 		assertThat(converted, is((org.springframework.data.geo.Point) point));
 	}
+
+	/**
+	 * @see DATAMONGO-1372
+	 */
+	@Test
+	public void convertsCurrencyToStringCorrectly() {
+		assertThat(CurrencyToStringConverter.INSTANCE.convert(Currency.getInstance("USD")), is("USD"));
+	}
+
+	/**
+	 * @see DATAMONGO-1372
+	 */
+	@Test
+	public void convertsStringToCurrencyCorrectly() {
+		assertThat(StringToCurrencyConverter.INSTANCE.convert("USD"), is(Currency.getInstance("USD")));
+	}
 }