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package examples;
import simulator.*;
import core.*;
import prefs.*;
import events.*;
import events.internal.*;
import events.implementations.*;
import serialize.VSSerialize;
import java.io.*;
import java.lang.reflect.*;
/**
* Creates a working Raft simulation by properly setting up the event queue
* and ensuring protocols are activated through the normal event system.
*/
public class CreateWorkingRaftSimulation {
private static final String RAFT_PROTOCOL = "protocols.implementations.VSRaftProtocol";
public static void main(String[] args) throws Exception {
System.out.println("=== Creating Working Raft Simulation ===\n");
// Initialize
VSDefaultPrefs prefs = new VSDefaultPrefs();
prefs.fillWithDefaults();
VSRegisteredEvents.init(prefs);
// Create simulator with frame
VSSimulatorFrame frame = new VSSimulatorFrame(prefs, null);
VSSimulator simulator = new VSSimulator(prefs, frame);
frame.addSimulator(simulator);
// Access visualization
Field vizField = VSSimulator.class.getDeclaredField("simulatorVisualization");
vizField.setAccessible(true);
VSSimulatorVisualization viz = (VSSimulatorVisualization) vizField.get(simulator);
// Add 5 processes (3 servers + 2 clients)
Method addProcessMethod = VSSimulatorVisualization.class.getDeclaredMethod("addProcess");
addProcessMethod.setAccessible(true);
System.out.println("Adding 5 processes...");
for (int i = 0; i < 5; i++) {
addProcessMethod.invoke(viz);
}
VSTaskManager taskManager = viz.getTaskManager();
// Schedule Raft server activations at time 0
System.out.println("\nScheduling Raft server activations:");
for (int i = 0; i < 3; i++) {
VSProtocolEvent serverEvent = new VSProtocolEvent();
serverEvent.setProtocolClassname(RAFT_PROTOCOL);
serverEvent.isClientProtocol(false); // Server mode
serverEvent.isProtocolActivation(true); // This is an activation
VSTask task = new VSTask(0, viz.getProcess(i), serverEvent, false);
taskManager.addTask(task);
System.out.println(" - Server " + i + " activation scheduled at time 0");
}
// Schedule Raft client activations with slight delay
System.out.println("\nScheduling Raft client activations:");
for (int i = 3; i < 5; i++) {
VSProtocolEvent clientEvent = new VSProtocolEvent();
clientEvent.setProtocolClassname(RAFT_PROTOCOL);
clientEvent.isClientProtocol(true); // Client mode
clientEvent.isProtocolActivation(true); // This is an activation
// Start clients after servers have initialized
long startTime = 500 + (i - 3) * 200;
VSTask task = new VSTask(startTime, viz.getProcess(i), clientEvent, false);
taskManager.addTask(task);
System.out.println(" - Client " + (i-3) + " activation scheduled at time " + startTime);
}
// Add some interesting events
System.out.println("\nAdding crash/recovery events:");
// Process 0 crashes at time 2000 and recovers at 3000
VSProcessCrashEvent crash1 = new VSProcessCrashEvent();
taskManager.addTask(new VSTask(2000, viz.getProcess(0), crash1, false));
System.out.println(" - Server 0 crash scheduled at time 2000");
VSProcessRecoverEvent recover1 = new VSProcessRecoverEvent();
taskManager.addTask(new VSTask(3000, viz.getProcess(0), recover1, false));
System.out.println(" - Server 0 recovery scheduled at time 3000");
// Process 1 crashes at time 4000 and recovers at 5000
VSProcessCrashEvent crash2 = new VSProcessCrashEvent();
taskManager.addTask(new VSTask(4000, viz.getProcess(1), crash2, false));
System.out.println(" - Server 1 crash scheduled at time 4000");
VSProcessRecoverEvent recover2 = new VSProcessRecoverEvent();
taskManager.addTask(new VSTask(5000, viz.getProcess(1), recover2, false));
System.out.println(" - Server 1 recovery scheduled at time 5000");
// Save simulation
File outputFile = new File("saved-simulations/raft-working.dat");
outputFile.getParentFile().mkdirs();
System.out.println("\nSaving simulation...");
VSSerialize serialize = new VSSerialize();
serialize.saveSimulator(outputFile.getAbsolutePath(), simulator);
frame.dispose();
System.out.println("\n✓ Simulation saved to: " + outputFile.getAbsolutePath());
// Create instruction file
File instructionFile = new File("saved-simulations/README-raft.txt");
try (PrintWriter writer = new PrintWriter(instructionFile)) {
writer.println("RAFT CONSENSUS SIMULATION");
writer.println("========================");
writer.println();
writer.println("This directory contains Raft consensus protocol simulations:");
writer.println();
writer.println("1. raft-working.dat - Full working simulation with:");
writer.println(" - 3 Raft servers (processes 0-2)");
writer.println(" - 2 Raft clients (processes 3-4)");
writer.println(" - Server crash/recovery events");
writer.println();
writer.println("To run the simulation:");
writer.println("1. java -jar target/ds-sim-1.0.1-SNAPSHOT.jar");
writer.println("2. File → Open → saved-simulations/raft-working.dat");
writer.println("3. Click Run (▶) button");
writer.println();
writer.println("What to look for:");
writer.println("- Leader election (REQUEST_VOTE messages)");
writer.println("- Heartbeats from leader (APPEND_ENTRIES)");
writer.println("- Client requests and responses");
writer.println("- Re-election when servers crash");
writer.println();
writer.println("Timeline:");
writer.println("- Time 0: Servers start, begin leader election");
writer.println("- Time 500-700: Clients start");
writer.println("- Time 2000: Server 0 crashes");
writer.println("- Time 3000: Server 0 recovers");
writer.println("- Time 4000: Server 1 crashes");
writer.println("- Time 5000: Server 1 recovers");
}
System.out.println("✓ Instructions saved to: " + instructionFile.getAbsolutePath());
System.out.println("\n=== Success! ===");
System.out.println("\nThe Raft simulation has been created with the following setup:");
System.out.println("- 3 servers implementing Raft consensus");
System.out.println("- 2 clients that will send requests");
System.out.println("- Crash/recovery events to test fault tolerance");
System.out.println("\nRun the simulator and load the file to see it in action!");
}
}
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