diff --git a/hibernate-c3p0/src/main/java/org/hibernate/c3p0/internal/C3P0ConnectionProvider.java b/hibernate-c3p0/src/main/java/org/hibernate/c3p0/internal/C3P0ConnectionProvider.java
index d41b2f8f42..df3a54284c 100644
--- a/hibernate-c3p0/src/main/java/org/hibernate/c3p0/internal/C3P0ConnectionProvider.java
+++ b/hibernate-c3p0/src/main/java/org/hibernate/c3p0/internal/C3P0ConnectionProvider.java
@@ -74,11 +74,11 @@ public class C3P0ConnectionProvider
 	private static final String C3P0_STYLE_MAX_STATEMENTS = "c3p0.maxStatements";
 	private static final String C3P0_STYLE_ACQUIRE_INCREMENT = "c3p0.acquireIncrement";
 	private static final String C3P0_STYLE_IDLE_CONNECTION_TEST_PERIOD = "c3p0.idleConnectionTestPeriod";
-
-	//swaldman 2006-08-28: define c3p0-style configuration parameters for initialPoolSize, which
-	//                     hibernate sensibly lets default to minPoolSize, but we'll let users
-	//                     override it with the c3p0-style property if they want.
+	//swaldman 2006-08-28: define c3p0-style configuration parameters for initialPoolSize,
+	//                     which hibernate sensibly lets default to minPoolSize, but we'll
+	//                     let users override it with the c3p0-style property if they want.
 	private static final String C3P0_STYLE_INITIAL_POOL_SIZE = "c3p0.initialPoolSize";
+
 	private DataSource dataSource;
 	private Integer isolation;
 	private boolean autocommit;
@@ -161,7 +161,7 @@ public void configure(Map<String, Object> properties) {
 				jdbcDriverClass,
 				dialect.getVersion(),
 				Boolean.toString( autocommit ),
-				isolation != null ? ConnectionProviderInitiator.toIsolationNiceName( isolation ) : null,
+				isolation == null ? null : ConnectionProviderInitiator.toIsolationNiceName( isolation ),
 				requireNonNullElse( getInteger( C3P0_STYLE_MIN_POOL_SIZE.substring( 5 ), poolSettings ),
 						DEFAULT_MIN_POOL_SIZE ),
 				requireNonNullElse( getInteger( C3P0_STYLE_MAX_POOL_SIZE.substring( 5 ), poolSettings ),
diff --git a/hibernate-core/src/main/java/org/hibernate/engine/jdbc/connections/internal/DriverManagerConnectionProviderImpl.java b/hibernate-core/src/main/java/org/hibernate/engine/jdbc/connections/internal/DriverManagerConnectionProviderImpl.java
index 0d1d1ca9f3..f4aece0826 100644
--- a/hibernate-core/src/main/java/org/hibernate/engine/jdbc/connections/internal/DriverManagerConnectionProviderImpl.java
+++ b/hibernate-core/src/main/java/org/hibernate/engine/jdbc/connections/internal/DriverManagerConnectionProviderImpl.java
@@ -21,7 +21,6 @@
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 import org.hibernate.HibernateException;
-import org.hibernate.Internal;
 import org.hibernate.boot.registry.classloading.spi.ClassLoaderService;
 import org.hibernate.cfg.AvailableSettings;
 import org.hibernate.dialect.Database;
@@ -338,7 +337,6 @@ public void stop() {
 		}
 	}
 
-	//CHECKSTYLE:START_ALLOW_FINALIZER
 	@Override
 	protected void finalize() throws Throwable {
 		if ( state != null ) {
@@ -346,26 +344,12 @@ protected void finalize() throws Throwable {
 		}
 		super.finalize();
 	}
-	//CHECKSTYLE:END_ALLOW_FINALIZER
-
-	/**
-	 * Exposed to facilitate testing only.
-	 */
-	public Properties getConnectionProperties() {
-		BasicConnectionCreator connectionCreator = (BasicConnectionCreator) this.state.pool.connectionCreator;
-		return connectionCreator.getConnectionProperties();
-	}
 
 	@Override
 	public boolean isValid(Connection connection) throws SQLException {
 		return true;
 	}
 
-	@Internal
-	public void releasePooledConnections() {
-		state.pool.releasePooledConnections();
-	}
-
 	public static class PooledConnections {
 
 		private final ConcurrentLinkedQueue<Connection> allConnections = new ConcurrentLinkedQueue<>();
@@ -438,7 +422,7 @@ protected Connection releaseConnection(Connection conn) {
 			return null;
 		}
 
-		public Connection poll() throws SQLException {
+		public Connection poll() {
 			Connection conn;
 			do {
 				conn = availableConnections.poll();
@@ -526,13 +510,6 @@ public String getUrl() {
 			return connectionCreator.getUrl();
 		}
 
-		@Internal
-		public void releasePooledConnections() {
-			for ( Connection connection : allConnections ) {
-				closeConnection( connection, null );
-			}
-		}
-
 		public static class Builder {
 			private final ConnectionCreator connectionCreator;
 			private ConnectionValidator connectionValidator;
@@ -641,7 +618,7 @@ public void stop() {
 			}
 		}
 
-		public Connection getConnection() throws SQLException {
+		public Connection getConnection() {
 			startIfNeeded();
 			statelock.readLock().lock();
 			try {
@@ -704,7 +681,6 @@ else if ( e != null ) {
 	}
 
 	private static class ValidationThreadFactory implements ThreadFactory {
-
 		@Override
 		public Thread newThread(Runnable runnable) {
 			Thread thread = new Thread( runnable );