#57 - Add support for R2DBC subclass exception translation.

We now use R2DBC's exception hierarchy to translate exceptions into Spring's DataAccessException hierarchy.

Original pull request: #97.

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

@@ -35,8 +35,9 @@ import org.springframework.data.r2dbc.function.DefaultReactiveDataAccessStrategy
 import org.springframework.data.r2dbc.function.ReactiveDataAccessStrategy;
 import org.springframework.data.r2dbc.function.convert.MappingR2dbcConverter;
 import org.springframework.data.r2dbc.function.convert.R2dbcCustomConversions;
+import org.springframework.data.r2dbc.support.R2dbcExceptionSubclassTranslator;
 import org.springframework.data.r2dbc.support.R2dbcExceptionTranslator;
-import org.springframework.data.r2dbc.support.SqlErrorCodeR2dbcExceptionTranslator;
+import org.springframework.data.r2dbc.support.SqlStateR2dbcExceptionTranslator;
 import org.springframework.data.relational.core.conversion.BasicRelationalConverter;
 import org.springframework.data.relational.core.mapping.NamingStrategy;
 import org.springframework.data.relational.core.mapping.RelationalMappingContext;
@@ -186,10 +187,12 @@ public abstract class AbstractR2dbcConfiguration implements ApplicationContextAw
 	 *
 	 * @return must not be {@literal null}.
 	 * @see #connectionFactory()
+	 * @see R2dbcExceptionSubclassTranslator
+	 * @see SqlStateR2dbcExceptionTranslator
 	 */
 	@Bean
 	public R2dbcExceptionTranslator exceptionTranslator() {
-		return new SqlErrorCodeR2dbcExceptionTranslator(lookupConnectionFactory());
+		return new R2dbcExceptionSubclassTranslator();
 	}
 
 	ConnectionFactory lookupConnectionFactory() {

src/main/java/org/springframework/data/r2dbc/function/DefaultDatabaseClientBuilder.java

@@ -23,8 +23,8 @@ import java.util.function.Consumer;
 import org.springframework.data.r2dbc.dialect.Database;
 import org.springframework.data.r2dbc.dialect.Dialect;
 import org.springframework.data.r2dbc.function.DatabaseClient.Builder;
+import org.springframework.data.r2dbc.support.R2dbcExceptionSubclassTranslator;
 import org.springframework.data.r2dbc.support.R2dbcExceptionTranslator;
-import org.springframework.data.r2dbc.support.SqlErrorCodeR2dbcExceptionTranslator;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
@@ -114,7 +114,7 @@ class DefaultDatabaseClientBuilder implements DatabaseClient.Builder {
 		R2dbcExceptionTranslator exceptionTranslator = this.exceptionTranslator;
 
 		if (exceptionTranslator == null) {
-			exceptionTranslator = new SqlErrorCodeR2dbcExceptionTranslator(connectionFactory);
+			exceptionTranslator = new R2dbcExceptionSubclassTranslator();
 		}
 
 		ReactiveDataAccessStrategy accessStrategy = this.accessStrategy;

src/main/java/org/springframework/data/r2dbc/support/AbstractFallbackR2dbcExceptionTranslator.java

@@ -19,6 +19,7 @@ import io.r2dbc.spi.R2dbcException;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+
 import org.springframework.dao.DataAccessException;
 import org.springframework.data.r2dbc.UncategorizedR2dbcException;
 import org.springframework.lang.NonNull;
@@ -99,7 +100,7 @@ public abstract class AbstractFallbackR2dbcExceptionTranslator implements R2dbcE
 	protected abstract DataAccessException doTranslate(String task, @Nullable String sql, R2dbcException ex);
 
 	/**
-	 * Build a message {@code String} for the given {@link java.sql.R2dbcException}.
+	 * Build a message {@code String} for the given {@link R2dbcException}.
 	 * <p>
 	 * To be called by translator subclasses when creating an instance of a generic
 	 * {@link org.springframework.dao.DataAccessException} class.
@@ -110,6 +111,6 @@ public abstract class AbstractFallbackR2dbcExceptionTranslator implements R2dbcE
 	 * @return the message {@code String} to use.
 	 */
 	protected String buildMessage(String task, @Nullable String sql, R2dbcException ex) {
-		return task + "; " + (sql != null ? "SQL [" + sql : "]; " + "") + ex.getMessage();
+		return task + "; " + (sql != null ? "SQL [" + sql + "]; " : "") + ex.getMessage();
 	}
 }

src/main/java/org/springframework/data/r2dbc/support/R2dbcExceptionSubclassTranslator.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2019 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
+ *
+ *      https://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.r2dbc.support;
+
+import io.r2dbc.spi.R2dbcBadGrammarException;
+import io.r2dbc.spi.R2dbcDataIntegrityViolationException;
+import io.r2dbc.spi.R2dbcException;
+import io.r2dbc.spi.R2dbcNonTransientException;
+import io.r2dbc.spi.R2dbcNonTransientResourceException;
+import io.r2dbc.spi.R2dbcPermissionDeniedException;
+import io.r2dbc.spi.R2dbcRollbackException;
+import io.r2dbc.spi.R2dbcTimeoutException;
+import io.r2dbc.spi.R2dbcTransientException;
+import io.r2dbc.spi.R2dbcTransientResourceException;
+
+import org.springframework.dao.ConcurrencyFailureException;
+import org.springframework.dao.DataAccessException;
+import org.springframework.dao.DataAccessResourceFailureException;
+import org.springframework.dao.DataIntegrityViolationException;
+import org.springframework.dao.PermissionDeniedDataAccessException;
+import org.springframework.dao.QueryTimeoutException;
+import org.springframework.dao.TransientDataAccessResourceException;
+import org.springframework.data.r2dbc.BadSqlGrammarException;
+import org.springframework.lang.Nullable;
+
+/**
+ * {@link R2dbcExceptionTranslator} implementation which analyzes the specific {@link R2dbcException} subclass thrown by
+ * the R2DBC driver.
+ * <p>
+ * Falls back to a standard {@link SqlStateR2dbcExceptionTranslator}.
+ *
+ * @author Mark Paluch
+ */
+public class R2dbcExceptionSubclassTranslator extends AbstractFallbackR2dbcExceptionTranslator {
+
+	public R2dbcExceptionSubclassTranslator() {
+		setFallbackTranslator(new SqlStateR2dbcExceptionTranslator());
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.r2dbc.support.AbstractFallbackR2dbcExceptionTranslator#doTranslate(java.lang.String, java.lang.String, io.r2dbc.spi.R2dbcException)
+	 */
+	@Override
+	@Nullable
+	protected DataAccessException doTranslate(String task, @Nullable String sql, R2dbcException ex) {
+
+		if (ex instanceof R2dbcTransientException) {
+			if (ex instanceof R2dbcTransientResourceException) {
+				return new TransientDataAccessResourceException(buildMessage(task, sql, ex), ex);
+			}
+			if (ex instanceof R2dbcRollbackException) {
+				return new ConcurrencyFailureException(buildMessage(task, sql, ex), ex);
+			}
+			if (ex instanceof R2dbcTimeoutException) {
+				return new QueryTimeoutException(buildMessage(task, sql, ex), ex);
+			}
+		}
+
+		if (ex instanceof R2dbcNonTransientException) {
+			if (ex instanceof R2dbcNonTransientResourceException) {
+				return new DataAccessResourceFailureException(buildMessage(task, sql, ex), ex);
+			}
+			if (ex instanceof R2dbcDataIntegrityViolationException) {
+				return new DataIntegrityViolationException(buildMessage(task, sql, ex), ex);
+			}
+			if (ex instanceof R2dbcPermissionDeniedException) {
+				return new PermissionDeniedDataAccessException(buildMessage(task, sql, ex), ex);
+			}
+			if (ex instanceof R2dbcBadGrammarException) {
+				return new BadSqlGrammarException(task, (sql != null ? sql : ""), ex);
+			}
+		}
+
+		// Fallback to Spring's own R2DBC state translation...
+		return null;
+	}
+}