HHH-10256 - ClassCastException in ResultSetReturnImpl.java:75

hibernate-c3p0/hibernate-c3p0.gradle

@@ -18,6 +18,12 @@ dependencies {
     testRuntime( libraries.expression_language_api )
     testRuntime( libraries.expression_language_impl )
 
+    if (db.equalsIgnoreCase("oracle")) {
+        dependencies {
+            testRuntime( libraries.oracle )
+        }
+    }
+
     // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     // Java 9 ftw!
     if ( JavaVersion.current().isJava9Compatible() ) {

hibernate-core/src/main/java/org/hibernate/engine/jdbc/internal/ResultSetReturnImpl.java

@@ -55,15 +55,16 @@ public class ResultSetReturnImpl implements ResultSetReturn {
 	@Override
 	public ResultSet extract(PreparedStatement statement) {
 		// IMPL NOTE : SQL logged by caller
-		if ( isTypeOf( statement, CallableStatement.class ) ) {
-			// We actually need to extract from Callable statement.  Although
-			// this seems needless, Oracle can return an
-			// OracleCallableStatementWrapper that finds its way to this method,
-			// rather than extract(CallableStatement).  See HHH-8022.
-			final CallableStatement callableStatement = (CallableStatement) statement;
-			return extract( callableStatement );
-		}
 		try {
+			if ( isTypeOf( statement, CallableStatement.class ) ) {
+				// We actually need to extract from Callable statement.  Although
+				// this seems needless, Oracle can return an
+				// OracleCallableStatementWrapper that finds its way to this method,
+				// rather than extract(CallableStatement).  See HHH-8022.
+				final CallableStatement callableStatement = statement.unwrap( CallableStatement.class );
+				return extract( callableStatement );
+			}
+
 			final ResultSet rs;
 			try {
 				jdbcExecuteStatementStart();

libraries.gradle

@@ -96,7 +96,8 @@ ext {
             postgresql:      'org.postgresql:postgresql:9.4-1202-jdbc41',
             mysql:             'mysql:mysql-connector-java:6.0.5',
             mariadb:         'org.mariadb.jdbc:mariadb-java-client:1.1.7',
-            oracle:          'com.oracle.ojdbc:ojdbc7:12.1.0.2.0',
+            oracle:          'com.oracle.jdbc:ojdbc7:12.1.0.2',
+
             mssql:             'com.microsoft.sqlserver:mssql-jdbc:6.1.0.jre8',
 
             informix:          'com.ibm.informix:jdbc:4.10.7.20160517',