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All Spring-managed classes should leverage the JaValid JSR303 Bean Validation Framework annotations for dependency checking of properties at deployment time. The default provider is Hibernate Validator.
Common Functionality
Wherever possible common functionality should be placed into an abstract or utility class, as applicable. A good example of this is the AbstractUsernamePasswordAuthenticationHandler, which most classes that use UsernamePasswordCredentials should extend from.
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We use Simple Logging Facade. In the case where we are extending an abstract class someone else provided for us, and if they were so kind as to provide a protected Logger instance for the runtime class, we'll try to use that. In the case where we create our own Log instance, we will name it "logger"log".
Perf4j
CAS4 utilizes the Per4j library for performance monitoring. We follow their recommended guidelines for annotating methods with @Profiled, which boils down to, if it does significant work then profile it. So, we're profiling the LDAP Authentication Handler, but not the Test Authentication Handler.
Qualifying instance variables with "this"
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