[AMQ-5959] NullPointerException in finally blocks

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 5.8.0, 5.12.0
• Fix Version/s: 5.12.1, 5.11.3, 5.13.0
• Component/s: Broker
• Labels: easyfix
• Assignee: Unassigned
• Reporter: William McDonald
• Created: 06/Sep/15 22:44
• Updated: 28/Oct/15 14:42
• Resolved: 08/Sep/15 14:06

Description

Try blocks including a finally block that references a potential null object generating a NullPointerException.

In The DestinationView.sendTextMessage(java.util.Map, ...) method for example (http://grepcode.com/file/repo1.maven.org/maven2/org.apache.activemq/activemq-broker/5.11.1/org/apache/activemq/broker/jmx/DestinationView.java#DestinationView.sendTextMessage%28java.util.Map%2Cjava.lang.String%2Cjava.lang.String%2Cjava.lang.String%29), I noticed code like the following:
Connection connection = null;
try

{ connection = cf.createConnection(userName, password); ... return msg.getJMSMessageID(); }

finally

{ connection.close(); }

There is no catch block and since an exception in the createConnection method could be thrown, connection would be null in the finally block, causing a NPE and masking the real exception.

There may be other forms of this bad style which a code style checker should be able to locate for you.