HikariCP 2.2.4 released

[Brett Wooldridge]

HikariCP 2.2.4 has been released and the artifacts published to the Maven Central Repository.

Sorry for the quick turns after 2.2.0 but a critical bug was reported soon after publishing.

Java 8 artifact:

  <dependency>
     <groupId>com.zaxxer</groupId>
     <artifactId>HikariCP</artifactId>
     <version>2.2.4</version>
     <scope>compile</scope>
  </dependency>

Java 6 / 7 artifact:
  <dependency>
     <groupId>com.zaxxer</groupId>
     <artifactId>HikariCP-java6</artifactId>
     <version>2.2.4</version>
     <scope>compile</scope>
  </dependency>

Important changes: the default value for initializationFailFast is now true, instead of false.  The jdbc4ConnectionTestproperty is now deprecated, JDBC4 support is now auto-detected.

Changes between 2.1.0 and 2.2.4

 * Generate proxy classes into the same protection domain as the HikariCP
   loaded classes.  This solves issues with signed jars.

 * Improve accuracy of pool statistics available to JMX and logged at debug
   level (at a slight performance cost).

 * Fixed issue where after a database down condition, and when minimumIdle is
   set to 0, when the database connectivity is restored the connections could
   ramp up to the maximum pool size.  Eventually, idleTimeout and maxLifetime
   would restore normal pool conditions, but it was still undesirable behavior.

 * Improved connection timeout handling by using Connection.setNetworkTimeout()
   if available (JDBC 4.1).

 * drvierClassName is no longer a required property when jdbcUrl is specified.
   Omitting this property only works for compliant drivers.

 * Add auto-detection of support for Statement.setQueryTimeout() used in the
   alive check.  Fixes failures with test queries on the PostgreSQL driver
   when not using JDBC4 isValid() alive checks.

 * The pool now defaults to fail-fast initialization.  If you need to start
   your application without/before the database, you will need to explicitly
   set initializationFailFast to false.

 * Dropwizard/Codahale metrics are now supported via the setMetricRegistry()
   method in HikariConfig and in HikariDataSource.

If you encounter any issues with HikariCP please report them on the github.com issue tracker.