Sciurus

Sciurus is a collection of useful aspects to

• monitor execution runtimes of methods
• lock method executions
• cache method results
• retry method executions on exceptions

General Usage

You need to include Sciurus as dependeny and declare it as an aspect library in the aspectj-maven-plugin.

1. Include Sciurus as dependency

   <dependency>
       <groupId>io.mcarle</groupId>
       <artifactId>sciurus</artifactId>
       <version>1.1.0</version>
   </dependency>
   

2. Include aspectj-maven-plugin and define Sciurus as aspectLibrary

   <plugin>
       <groupId>org.codehaus.mojo</groupId>
       <artifactId>aspectj-maven-plugin</artifactId>
       <version>1.11</version>
       <executions>
           <execution>
               <goals>
                   <goal>compile</goal>
                   <goal>test-compile</goal>
               </goals>
           </execution>
       </executions>
       <configuration>
           <complianceLevel>${maven.compiler.source}</complianceLevel>
           <source>${maven.compiler.source}</source>
           <target>${maven.compiler.target}</target>
           <aspectLibraries>
               <aspectLibrary>
                   <groupId>io.mcarle</groupId>
                   <artifactId>sciurus</artifactId>
               </aspectLibrary>
           </aspectLibraries>
       </configuration>
   </plugin>
   

Use Case Examples

There are a number of possible use cases for each aspect.

@Monitor

• Notify a monitoring application
• Find bottlenecks
• Test the speed of a new software version before deploying it in production
• Store execution times (e.g. in a database) and
  • see how they evolve over time
  • see runaway values
  • monitor them through a MBean

@Cache

• Caching (surprise!)
• Facade for various caches which can be exchanged with merely little code changes

@Lock

• Prevent multiple storing (e.g. in databases)
• Prevent multiple execution of long running or high cpu consuming methods (e.g. in combination with @Cache)

@Retry

• Retry storing entities into the database due to locking exceptions
• Retry a failed connection to a web service
• Retry a method which may lead to some random or temporary incidents

More information and example

https://github.com/mcarleio/sciurus