Polishing.

Original pull request 1384
See #833

Author: schauder

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/core/convert/SqlGenerator.java

@@ -57,6 +57,7 @@
  * @author Chirag Tailor
  * @author Diego Krupitza
  * @author Hari Ohm Prasath
+ * @author Viktor Ardelean
  */
 class SqlGenerator {
 
@@ -260,10 +261,10 @@ private Condition buildConditionForBackReference(Identifier parentIdentifier, Ta
 
 		Condition condition = null;
 		for (SqlIdentifier backReferenceColumn : parentIdentifier.toMap().keySet()) {
-			if (SqlIdentifier.EMPTY.equals(backReferenceColumn)){
-				throw new UnsupportedOperationException(
-						"An empty SqlIdentifier can't be used in condition. Make sure that all composite primary keys are defined in the query.");
-			}
+
+			Assert.isTrue(!SqlIdentifier.EMPTY.equals(backReferenceColumn),
+					"An empty SqlIdentifier can't be used in condition. Make sure that all composite primary keys are defined in the query");
+
 			Condition newCondition = table.column(backReferenceColumn).isEqualTo(getBindMarker(backReferenceColumn));
 			condition = condition == null ? newCondition : condition.and(newCondition);
 		}
@@ -1102,7 +1103,7 @@ private void initSimpleColumnName(RelationalPersistentProperty property, String
 			if (!property.isWritable()) {
 				readOnlyColumnNames.add(columnName);
 			}
-		if (property.isInsertOnly()) {
+			if (property.isInsertOnly()) {
 				insertOnlyColumnNames.add(columnName);
 			}
 		}

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/core/convert/SqlGeneratorUnitTests.java

@@ -26,7 +26,6 @@
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
-
 import org.springframework.data.annotation.Id;
 import org.springframework.data.annotation.ReadOnlyProperty;
 import org.springframework.data.annotation.Version;
@@ -72,6 +71,7 @@
  * @author Chirag Tailor
  * @author Diego Krupitza
  * @author Hari Ohm Prasath
+ * @author Viktor Ardelean
  */
 @SuppressWarnings("Convert2MethodRef")
 class SqlGeneratorUnitTests {
@@ -443,15 +443,14 @@ public void findAllByPropertyAvoidsDuplicateColumns() {
 
 	}
 
-	@Test // DATAJDBC-613
+	@Test // GH-833
 	void findAllByPropertyWithEmptyBackrefColumn() {
 
-		assertThatThrownBy(() -> {
-			sqlGenerator.getFindAllByProperty(Identifier.of(EMPTY, 0, Object.class),
-					unquoted("key-column"),
-					false);
-		}).isInstanceOf(UnsupportedOperationException.class)
-				.hasMessageContaining("An empty SqlIdentifier can't be used in condition. Make sure that all composite primary keys are defined in the query.");
+		Identifier emptyIdentifier = Identifier.of(EMPTY, 0, Object.class);
+		assertThatThrownBy(() -> sqlGenerator.getFindAllByProperty(emptyIdentifier, unquoted("key-column"), false)) //
+				.isInstanceOf(IllegalArgumentException.class) //
+				.hasMessageContaining(
+						"An empty SqlIdentifier can't be used in condition. Make sure that all composite primary keys are defined in the query");
 	}
 
 	@Test // DATAJDBC-219