From 82b376c5f6f5cafca6381adab8764fb6f525c672 Mon Sep 17 00:00:00 2001
From: Sanne Grinovero <sanne@hibernate.org>
Date: Sat, 15 Nov 2014 19:04:17 +0000
Subject: [PATCH] HHH-9498 Using C3P0 connection pool but not setting
 hibernate.connection.isolation results in a NumberFormatException

---
 .../c3p0/internal/C3P0ConnectionProvider.java         |  3 ++-
 .../test/c3p0/C3P0ConnectionProviderTest.java         | 11 +++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

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 6f55c363dc..c288282346 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
@@ -38,6 +38,7 @@ import org.hibernate.boot.registry.classloading.spi.ClassLoadingException;
 import org.hibernate.cfg.Environment;
 import org.hibernate.engine.jdbc.connections.internal.ConnectionProviderInitiator;
 import org.hibernate.engine.jdbc.connections.spi.ConnectionProvider;
+import org.hibernate.internal.util.StringHelper;
 import org.hibernate.internal.util.config.ConfigurationHelper;
 import org.hibernate.service.UnknownUnwrapTypeException;
 import org.hibernate.service.spi.Configurable;
@@ -214,7 +215,7 @@ public class C3P0ConnectionProvider
 		}
 
 		final String i = (String) props.get( Environment.ISOLATION );
-		if ( i == null ) {
+		if ( StringHelper.isEmpty( i ) ) {
 			isolation = null;
 		}
 		else {
diff --git a/hibernate-c3p0/src/test/java/org/hibernate/test/c3p0/C3P0ConnectionProviderTest.java b/hibernate-c3p0/src/test/java/org/hibernate/test/c3p0/C3P0ConnectionProviderTest.java
index 904806f366..9840f45447 100644
--- a/hibernate-c3p0/src/test/java/org/hibernate/test/c3p0/C3P0ConnectionProviderTest.java
+++ b/hibernate-c3p0/src/test/java/org/hibernate/test/c3p0/C3P0ConnectionProviderTest.java
@@ -24,14 +24,17 @@
 package org.hibernate.test.c3p0;
 
 import java.lang.management.ManagementFactory;
+import java.util.Properties;
 import java.util.Set;
 import javax.management.MBeanServer;
 import javax.management.ObjectName;
 
 import org.hibernate.c3p0.internal.C3P0ConnectionProvider;
+import org.hibernate.cfg.Environment;
 import org.hibernate.engine.jdbc.connections.spi.ConnectionProvider;
 import org.hibernate.engine.jdbc.spi.JdbcServices;
 
+import org.hibernate.testing.TestForIssue;
 import org.junit.Test;
 
 import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
@@ -89,4 +92,12 @@ public class C3P0ConnectionProviderTest extends BaseCoreFunctionalTestCase {
 
         assertTrue( "PooledDataSource BMean not found, please verify version of c3p0", mbeanfound );
     }
+
+    @Test @TestForIssue(jiraKey="HHH-9498")
+    public void testIsolationPropertyCouldBeEmpty() {
+        Properties configuration = new Properties();
+        configuration.setProperty( Environment.ISOLATION, "" );
+        C3P0ConnectionProvider provider = new C3P0ConnectionProvider();
+        provider.configure( configuration );
+    }
 }