Fix #199 fix possible race, while avoiding heavy weight synchronisation

hikaricp-java6/src/main/java/com/zaxxer/hikari/util/PoolUtilities.java

@@ -234,8 +234,6 @@ public final class PoolUtilities
    public static boolean isJdbc40Compliant(final Connection connection) throws SQLException
    {
       if (!jdbc40checked) {
-         jdbc40checked = true;
-         
          try {
             connection.isValid(5);  // This will throw AbstractMethodError or SQLException in the case of a non-JDBC 41 compliant driver
             IS_JDBC40 = true;
@@ -249,6 +247,9 @@ public final class PoolUtilities
          catch (NoSuchMethodError e) {
             IS_JDBC40 = false;
          }
+         finally {
+            jdbc40checked = true;
+         }
       }
       
       return IS_JDBC40;
@@ -293,8 +294,6 @@ public final class PoolUtilities
    public static int setNetworkTimeout(final Executor executor, final Connection connection, final long timeoutMs, final boolean isUseNetworkTimeout) throws SQLException
    {
       if ((IS_JDBC41 || !jdbc41checked) && isUseNetworkTimeout) {
-         jdbc41checked = true;
-
          try {
             final int networkTimeout = connection.getNetworkTimeout();
             connection.setNetworkTimeout(executor, (int) timeoutMs);
@@ -310,6 +309,9 @@ public final class PoolUtilities
          catch (NoSuchMethodError e) {
             IS_JDBC41 = false;
          }
+         finally {
+            jdbc41checked = true;
+         }
       }
 
       return 0;

hikaricp/src/main/java/com/zaxxer/hikari/util/PoolUtilities.java

@@ -216,8 +216,6 @@ public final class PoolUtilities
    public static boolean isJdbc40Compliant(final Connection connection) throws SQLException
    {
       if (!jdbc40checked) {
-         jdbc40checked = true;
-         
          try {
             connection.isValid(5);  // This will throw AbstractMethodError or SQLException in the case of a non-JDBC 41 compliant driver
             IS_JDBC40 = true;
@@ -225,6 +223,9 @@ public final class PoolUtilities
          catch (NoSuchMethodError | AbstractMethodError | SQLFeatureNotSupportedException e) {
             IS_JDBC40 = false;
          }
+         finally {
+            jdbc40checked = true;
+         }
       }
       
       return IS_JDBC40;
@@ -263,8 +264,6 @@ public final class PoolUtilities
    public static int setNetworkTimeout(final Executor executor, final Connection connection, final long timeoutMs, final boolean isUseNetworkTimeout) throws SQLException
    {
       if ((IS_JDBC41 || !jdbc41checked) && isUseNetworkTimeout) {
-         jdbc41checked = true;
-
          try {
             final int networkTimeout = connection.getNetworkTimeout();
             connection.setNetworkTimeout(executor, (int) timeoutMs);
@@ -274,6 +273,9 @@ public final class PoolUtilities
          catch (SQLFeatureNotSupportedException | AbstractMethodError | NoSuchMethodError e) {
             IS_JDBC41 = false;
          }
+         finally {
+            jdbc41checked = true;
+         }
       }
 
       return 0;