RMI Remote Method Invocation

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RMI Remote Method Invocation

• Java n tier Applications

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RMI-Client, Server
Client
RMI
Server
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RMI Setup

• Shared interface for client and server
• Extend UnicastRemoteObject ends with Impl
• Impl File Preparation
• Create client source file
• Create server source file
• Create policy file
• Start RMI server
• Start client

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Shared interface for client and server

• import java.rmi.
• public interface Product extends Remote
• String getDescription() throws RemoteException

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Extend UnicastRemoteObject

• import java.rmi.
• import java.rmi.server.
• public class ProductImpl extends
  UnicastRemoteObject
• implements Product
• //Define constructors and methods in this class
  definition file.

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Impl File Preparation

• javac Impl source file
• javac ProductImpl.java
• rmic Impl class file
• rmic ProductImpl

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Create client source file

• import java.rmi.
• import java.rmi.server.
• public class ProductClient
• public static void main(String args)

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Impl File Preparation main() method code

• System.setSecurityManager(new
  RMISecurityManager())
• String url "rmi//127.0.0.1/"
• try
• Product p (Product)Naming.lookup(url
  "Glendale")
• System.out.println(p.getDescription())
• catch(Exception e)
• System.out.println("Found a client error -
  " e.getMessage())

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Create server source file

• import java.rmi.
• import java.rmi.server.
• public class RMIServerTest
• public static void main(String args)
• try
• ProductImpl pl new ProductImpl("Glendale")
  
• Naming.rebind("Glendale", pl)
• System.out.println("Waiting for
  connection")
• catch(Exception e)
• System.out.println("Caught an exception - "
  e.getMessage())

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Create Policy File

• grant
• permission java.net.SocketPermission
• "1024-65535", "connect"

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Start RMI server

• start rmiregistry
• java RMIServerTest

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Start client

• java Djava.security.policyclient.policy
  ProductClient

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RMI Issues

• Deployment
• server
• download
• client
• Serialization

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Other n tier Technologies

• CORBA
• COM
• DCOM