ALMI (Abstraction Layer for Multiserver Infrastructure)

Description

ALMI is a Java multiserver framework for remote method calls management based on Netty and Jackson serialization, that adds an abstraction layer for multiserver communication.

This framework will semplify the cluster management, making methods accessibile from other server, that has ALMI running on a node in the cluster.

Setup

Add ALMI dependencies in your pom.xml or eventually, go to the Maven Repository and download the jar library file.

<dependencies>
    <dependency>
        <groupId>com.matteobattilana</groupId>
        <artifactId>almi</artifactId>
        <version>0.1.5</version>
    </dependency>
</dependencies>

Simple usage

The following code will instantiate an ALMI server that is listening on the 8888 port. If not set, it will use the one described in the Default configuration section).

Almi server = AlmiBootstrap.bootstrap()
          .withPort(8888)
          .withMethodsMapper(new MethodsMapper()
          {
              @Override
              public void configure()
                throws Exception
              {
                  addMethods(
                    bindStatic(Calculator.class)
                       .method("execute", double.class, Calculator.Operation.class, double.class)
                       .withDefaultName(),
                    bind(new Calculator())
                       .method(Calculator.class.getMethod("sqrt", double.class))
                       .withName("positiveSqrt")
                  );
              }
          })
          .start();

MethodsMapper

MethodsMapper will let you define the mapping beetwen the local method implementation and its remote name. This is used to make methods accessibile from other ALMI server, running on a node in the cluster.

A MethodsMapper can be defined in-line as the one in previous example, or in a specific class. The addMethods will configure the methods passed as arguments, in order to expose them.

Every binded method must implements Serializable!

public class MethodMapperImpl extends MethodsMapper
{
    @Override
    public void configure()
      throws Exception
    {
        addMethods(
          bind(mInstance)
            .method(CustomClass.class.getMethod("methodName"))
            .withDefaultName(),
          bindStatic(CustomClass.class)
            .method(ClientInformation.class.getMethod("staticMethodName"))
            .withDefaultName()
          );
    }
}

Bind static method

    addMethods(
      bindStatic(ClassName.class)
        .method(ClassName.class.getMethod("staticMethodName"))
        .withDefaultName()
    );

Bind instance method

    addMethods(
      bind(mInstance)
        .method(ClassName.class.getMethod("methodName"))
        .withName("methodName")
    );

Configuration

Default configuration

The defaul configuration loaded from static constants from the Constants.java:

DEFAULT_PORT               = 8888;
DEFAULT_CONNECTION_TIMEOUT = 10000;
DEFAULT_PROMISE_TIMEOUT    = 10000;
DEFAULT_THREAD_NAME        = "almi-service";