add error handling for Query and ViewQuery methods

src/main/java/org/springframework/data/couchbase/core/CouchbaseExceptionTranslator.java

@@ -38,11 +38,13 @@ import com.couchbase.client.java.error.InvalidPasswordException;
 import com.couchbase.client.java.error.RequestTooBigException;
 import com.couchbase.client.java.error.TemporaryFailureException;
 import com.couchbase.client.java.error.TemporaryLockFailureException;
+import com.couchbase.client.java.error.TranscodingException;
 import com.couchbase.client.java.error.ViewDoesNotExistException;
 
 import org.springframework.dao.DataAccessException;
 import org.springframework.dao.DataAccessResourceFailureException;
 import org.springframework.dao.DataIntegrityViolationException;
+import org.springframework.dao.DataRetrievalFailureException;
 import org.springframework.dao.DuplicateKeyException;
 import org.springframework.dao.InvalidDataAccessResourceUsageException;
 import org.springframework.dao.QueryTimeoutException;
@@ -115,6 +117,12 @@ public class CouchbaseExceptionTranslator implements PersistenceExceptionTransla
 			return new QueryTimeoutException(ex.getMessage(), ex);
 		}
 
+		if (ex instanceof TranscodingException) {
+			//note: the more specific CouchbaseQueryExecutionException should be thrown by the template
+			//when dealing with TranscodingException in the query/n1ql methods.
+			return new DataRetrievalFailureException(ex.getMessage(), ex);
+		}
+
 		// Unable to translate exception, therefore just throw the original!
 		throw ex;
 	}

src/main/java/org/springframework/data/couchbase/core/CouchbaseQueryExecutionException.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2012-2015 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 org.springframework.data.couchbase.core;
+
+import org.springframework.dao.DataRetrievalFailureException;
+
+/**
+ * An {@link DataRetrievalFailureException} that denotes an error during a query (N1QL).
+ */
+public class CouchbaseQueryExecutionException extends DataRetrievalFailureException {
+
+	public CouchbaseQueryExecutionException(String msg) {
+		super(msg);
+	}
+
+	public CouchbaseQueryExecutionException(String msg, Throwable cause) {
+		super(msg, cause);
+	}
+}

src/main/java/org/springframework/data/couchbase/core/CouchbaseTemplate.java

@@ -31,7 +31,9 @@ import com.couchbase.client.java.PersistTo;
 import com.couchbase.client.java.ReplicateTo;
 import com.couchbase.client.java.document.Document;
 import com.couchbase.client.java.document.RawJsonDocument;
+import com.couchbase.client.java.document.json.JsonObject;
 import com.couchbase.client.java.error.CASMismatchException;
+import com.couchbase.client.java.error.TranscodingException;
 import com.couchbase.client.java.query.Query;
 import com.couchbase.client.java.query.QueryResult;
 import com.couchbase.client.java.query.QueryRow;
@@ -262,16 +264,24 @@ public class CouchbaseTemplate implements CouchbaseOperations, ApplicationEventP
 		query.includeDocs(false);
 		query.reduce(false);
 
-		final ViewResult response = queryView(query);
+		try {
-		List<ViewRow> allRows = response.allRows();
+			final ViewResult response = queryView(query);
-		//TODO error handling
+			if (response.error() != null) {
+				throw new CouchbaseQueryExecutionException("Unable to execute view query due to the following view error: " +
+						response.error().toString());
+			}
 
-		final List<T> result = new ArrayList<T>(allRows.size());
+			List<ViewRow> allRows = response.allRows();
-		for (final ViewRow row : allRows) {
+
-			result.add(mapToEntity(row.id(), row.document(RawJsonDocument.class), entityClass));
+			final List<T> result = new ArrayList<T>(allRows.size());
+			for (final ViewRow row : allRows) {
+				result.add(mapToEntity(row.id(), row.document(RawJsonDocument.class), entityClass));
+			}
+
+			return result;
+		} catch (TranscodingException e) {
+			throw new CouchbaseQueryExecutionException("Unable to execute view query", e);
 		}
-
-		return result;
 	}
 
 	@Override
@@ -286,17 +296,28 @@ public class CouchbaseTemplate implements CouchbaseOperations, ApplicationEventP
 
 	@Override
 	public <T> List<T> findByN1QL(Query n1ql, Class<T> entityClass) {
-		QueryResult queryResult = queryN1QL(n1ql);
+		try {
+			QueryResult queryResult = queryN1QL(n1ql);
 
-		List<QueryRow> allRows = queryResult.allRows();
+			if (queryResult.finalSuccess()) {
-		List<T> result = new ArrayList<T>(allRows.size());
+				List<QueryRow> allRows = queryResult.allRows();
-		for (QueryRow row : allRows) {
+				List<T> result = new ArrayList<T>(allRows.size());
-			String json = row.value().toString();
+				for (QueryRow row : allRows) {
-			T decoded = translationService.decodeFragment(json, entityClass);
+					String json = row.value().toString();
-			result.add(decoded);
+					T decoded = translationService.decodeFragment(json, entityClass);
+					result.add(decoded);
+				}
+				return result;
+			} else {
+				StringBuilder message = new StringBuilder("Unable to execute query due to the following n1ql errors: ");
+				for (JsonObject error : queryResult.errors()) {
+					message.append('\n').append(error);
+				}
+				throw new CouchbaseQueryExecutionException(message.toString());
+			}
+		} catch (TranscodingException e) {
+			throw new CouchbaseQueryExecutionException("Unable to execute query", e);
 		}
-		//TODO error handling
-		return result;
 	}
 
 	@Override