#166 - Polishing.

Consider Dialect-specific converters also in DatabaseClient.create(…) factory. Reduce constant visibility. Add tests. Reformat code.

Original pull request: #168.

Author: mp911de

src/main/java/org/springframework/data/r2dbc/config/AbstractR2dbcConfiguration.java

@@ -17,7 +17,9 @@
 
 import io.r2dbc.spi.ConnectionFactory;
 
+import java.util.ArrayList;
 import java.util.Collections;
+import java.util.List;
 import java.util.Optional;
 
 import org.springframework.beans.BeansException;
@@ -174,7 +176,11 @@ public R2dbcCustomConversions r2dbcCustomConversions() {
 	protected StoreConversions getStoreConversions() {
 
 		R2dbcDialect dialect = getDialect(lookupConnectionFactory());
-		return StoreConversions.of(dialect.getSimpleTypeHolder(), dialect.getConverters(), R2dbcCustomConversions.STORE_CONVERTERS);
+
+		List<Object> converters = new ArrayList<>(dialect.getConverters());
+		converters.addAll(R2dbcCustomConversions.STORE_CONVERTERS);
+
+		return StoreConversions.of(dialect.getSimpleTypeHolder(), converters);
 	}
 
 	/**

src/main/java/org/springframework/data/r2dbc/core/DefaultReactiveDataAccessStrategy.java

@@ -82,13 +82,23 @@ public DefaultReactiveDataAccessStrategy(R2dbcDialect dialect, Collection<?> con
 		this(dialect, createConverter(dialect, converters));
 	}
 
+	/**
+	 * Creates a new {@link R2dbcConverter} given {@link R2dbcDialect} and custom {@code converters}.
+	 *
+	 * @param dialect must not be {@literal null}.
+	 * @param converters must not be {@literal null}.
+	 * @return the {@link R2dbcConverter}.
+	 */
 	public static R2dbcConverter createConverter(R2dbcDialect dialect, Collection<?> converters) {
 
 		Assert.notNull(dialect, "Dialect must not be null");
 		Assert.notNull(converters, "Converters must not be null");
 
+		List<Object> storeConverters = new ArrayList<>(dialect.getConverters());
+		storeConverters.addAll(R2dbcCustomConversions.STORE_CONVERTERS);
+
 		R2dbcCustomConversions customConversions = new R2dbcCustomConversions(
-				StoreConversions.of(dialect.getSimpleTypeHolder(), R2dbcCustomConversions.STORE_CONVERTERS), converters);
+				StoreConversions.of(dialect.getSimpleTypeHolder(), storeConverters), storeConverters);
 
 		RelationalMappingContext context = new RelationalMappingContext();
 		context.setSimpleTypeHolder(customConversions.getSimpleTypeHolder());

src/main/java/org/springframework/data/r2dbc/dialect/MySqlDialect.java

@@ -18,14 +18,14 @@
 import java.net.InetAddress;
 import java.net.URI;
 import java.net.URL;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 import java.util.UUID;
+
 import org.springframework.core.convert.converter.Converter;
 
 /**
@@ -45,19 +45,11 @@ public class MySqlDialect extends org.springframework.data.relational.core.diale
 	public static final MySqlDialect INSTANCE = new MySqlDialect();
 
 	private static final BindMarkersFactory ANONYMOUS = BindMarkersFactory.anonymous("?");
-	
+
 	/**
-	 * MySql specific converters.
+	 * MySQL specific converters.
 	 */
-	public static final List<Object> CONVERTERS;
-	
-	static {
-		List<Object> converters = new ArrayList<>();
-
-		converters.add(ByteToBooleanConverter.INSTANCE);
-
-		CONVERTERS = Collections.unmodifiableList(converters);
-	}
+	private static final List<Object> CONVERTERS = Collections.singletonList(ByteToBooleanConverter.INSTANCE);
 
 	/*
 	 * (non-Javadoc)
@@ -76,7 +68,7 @@ public BindMarkersFactory getBindMarkersFactory() {
 	public Collection<? extends Class<?>> getSimpleTypes() {
 		return SIMPLE_TYPES;
 	}
-	
+
 	/*
 	 * (non-Javadoc)
 	 * @see org.springframework.data.r2dbc.dialect.R2dbcDialect#getConverters()
@@ -85,11 +77,10 @@ public Collection<? extends Class<?>> getSimpleTypes() {
 	public Collection<Object> getConverters() {
 		return CONVERTERS;
 	}
-        
+
 	/**
-	 * Simple singleton to convert {@link Byte}s to their {@link Boolean}
-	 * representation. MySQL does not have a built in boolean type by default,
-	 * so relies on using a byte instead. Non-zero values represent true.
+	 * Simple singleton to convert {@link Byte}s to their {@link Boolean} representation. MySQL does not have a built-in
+	 * boolean type by default, so relies on using a byte instead. Non-zero values represent {@literal true}.
 	 *
 	 * @author Michael Berry
 	 */
@@ -99,9 +90,11 @@ public enum ByteToBooleanConverter implements Converter<Byte, Boolean> {
 
 		@Override
 		public Boolean convert(Byte s) {
+
 			if (s == null) {
 				return null;
 			}
+
 			return s != 0;
 		}
 	}

src/main/java/org/springframework/data/r2dbc/dialect/R2dbcDialect.java

@@ -14,6 +14,7 @@
  *
  * @author Mark Paluch
  * @author Jens Schauder
+ * @author Michael Berry
  */
 public interface R2dbcDialect extends Dialect {
 
@@ -51,7 +52,7 @@ default SimpleTypeHolder getSimpleTypeHolder() {
 
 	/**
 	 * Return a collection of converters for this dialect.
-	 * 
+	 *
 	 * @return a collection of converters for this dialect.
 	 */
 	default Collection<Object> getConverters() {

src/test/java/org/springframework/data/r2dbc/core/MySqlDatabaseClientIntegrationTests.java

@@ -15,14 +15,22 @@
  */
 package org.springframework.data.r2dbc.core;
 
+import static org.assertj.core.api.Assertions.*;
+
 import io.r2dbc.spi.ConnectionFactory;
+import lombok.Data;
+import reactor.test.StepVerifier;
 
 import javax.sql.DataSource;
 
 import org.junit.ClassRule;
+import org.junit.Test;
 
+import org.springframework.dao.DataAccessException;
 import org.springframework.data.r2dbc.testing.ExternalDatabase;
 import org.springframework.data.r2dbc.testing.MySqlTestSupport;
+import org.springframework.data.relational.core.mapping.Table;
+import org.springframework.jdbc.core.JdbcTemplate;
 
 /**
  * Integration tests for {@link DatabaseClient} against MySQL.
@@ -47,4 +55,42 @@ protected ConnectionFactory createConnectionFactory() {
 	protected String getCreateTableStatement() {
 		return MySqlTestSupport.CREATE_TABLE_LEGOSET;
 	}
+
+	@Test // gh-166
+	public void considersBuiltInConverters() {
+
+		ConnectionFactory connectionFactory = createConnectionFactory();
+		JdbcTemplate jdbc = createJdbcTemplate(createDataSource());
+
+		try {
+			jdbc.execute("DROP TABLE boolean_mapping");
+		} catch (DataAccessException e) {}
+		jdbc.execute("CREATE TABLE boolean_mapping (id int, flag1 TINYINT, flag2 TINYINT)");
+
+		BooleanMapping mapping = new BooleanMapping();
+		mapping.setId(42);
+		mapping.setFlag1(true);
+
+		DatabaseClient databaseClient = DatabaseClient.create(connectionFactory);
+
+		databaseClient.insert().into(BooleanMapping.class).using(mapping).then() //
+				.as(StepVerifier::create) //
+				.verifyComplete();
+
+		databaseClient.select().from(BooleanMapping.class).fetch().first() //
+				.as(StepVerifier::create) //
+				.consumeNextWith(actual -> assertThat(actual.isFlag1()).isTrue()) //
+				.verifyComplete();
+	}
+
+	@Table("boolean_mapping")
+	@Data
+	static class BooleanMapping {
+
+		int id;
+		boolean flag1;
+		boolean flag2;
+
+	}
+
 }