improve oracle exception sorter error code

src/test/java/com/alibaba/druid/bvt/pool/exception/OracleExceptionSorter_userDefined.java

@@ -0,0 +1,34 @@
+package com.alibaba.druid.bvt.pool.exception;
+
+import java.sql.SQLException;
+
+import junit.framework.TestCase;
+
+import org.junit.Assert;
+
+import com.alibaba.druid.pool.vendor.OracleExceptionSorter;
+
+public class OracleExceptionSorter_userDefined extends TestCase {
+
+    protected void setUp() throws Exception {
+        System.setProperty("druid.oracle.fatalErrorCodes", "1,2,3,a,");
+    }
+
+    protected void tearDown() throws Exception {
+        System.clearProperty("druid.oracle.fatalErrorCodes");
+    }
+
+    public void test_userDefinedErrorCodes() throws Exception {
+        OracleExceptionSorter sorter = new OracleExceptionSorter();
+        Assert.assertEquals(3, sorter.getFatalErrorCodes().size());
+        Assert.assertTrue(sorter.getFatalErrorCodes().contains(1));
+        Assert.assertTrue(sorter.getFatalErrorCodes().contains(2));
+        Assert.assertTrue(sorter.getFatalErrorCodes().contains(3));
+
+        Assert.assertTrue(sorter.isExceptionFatal(new SQLException("xx", "xx", 1)));
+        Assert.assertTrue(sorter.isExceptionFatal(new SQLException("xx", "xx", 2)));
+        Assert.assertTrue(sorter.isExceptionFatal(new SQLException("xx", "xx", 3)));
+        Assert.assertFalse(sorter.isExceptionFatal(new SQLException("xx", "xx", 4)));
+        Assert.assertTrue(sorter.isExceptionFatal(new SQLException("xx", "xx", 28)));
+    }
+}