transition enricher

state_machines/complex_multi_module_sm/service/.gitignore

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+HELP.md
+target/
+.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

state_machines/complex_multi_module_sm/service/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>click.kamil.complex</groupId>
+        <artifactId>complex-multi-module-sm</artifactId>
+        <version>1.0.0</version>
+    </parent>
+
+    <artifactId>service</artifactId>
+
+    <dependencies>
+        <dependency>
+            <groupId>click.kamil.complex</groupId>
+            <artifactId>domain</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.statemachine</groupId>
+            <artifactId>spring-statemachine-core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-tx</artifactId>
+        </dependency>
+    </dependencies>
+</project>

state_machines/complex_multi_module_sm/service/src/main/java/click/kamil/service/OutboxAction.java

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+package click.kamil.service;
+
+import click.kamil.domain.IEvent;
+
+public interface OutboxAction<T extends IEvent> {
+    void onCommit(T event);
+}

state_machines/complex_multi_module_sm/service/src/main/java/click/kamil/service/StateMachineService.java

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+package click.kamil.service;
+
+import click.kamil.domain.IEvent;
+import click.kamil.domain.IState;
+
+public interface StateMachineService {
+    <S extends IState, T extends IEvent> void sendMessage(T event);
+
+    <S extends IState, T extends IEvent, A extends OutboxAction<T>> void sendMessageWithOutbox(T event, A action);
+
+    // Quirky pattern: Bounded generic supplier instead of reflection
+    <T extends click.kamil.domain.OrderEvent> void sendMessageWithProvider(java.util.function.Supplier<T> eventProvider);
+
+    // Quirky pattern 2: Generic Varargs
+    <T extends IEvent> void sendEventsVarargs(T... events);
+
+    // Quirky pattern 3: Multiple generic bounds (Intersection Types)
+    <T extends IEvent & java.io.Serializable & Cloneable> T processQuirkyEvent(T event);
+}

state_machines/complex_multi_module_sm/service/src/main/java/click/kamil/service/StateMachineServiceImpl.java

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+package click.kamil.service;
+
+import click.kamil.domain.IEvent;
+import click.kamil.domain.IState;
+import click.kamil.domain.OrderEvent;
+import click.kamil.domain.OrderState;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.messaging.support.MessageBuilder;
+import org.springframework.statemachine.StateMachine;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import org.springframework.transaction.support.TransactionSynchronization;
+import org.springframework.transaction.support.TransactionSynchronizationManager;
+import reactor.core.publisher.Mono;
+
+@Service
+public class StateMachineServiceImpl implements StateMachineService {
+
+    @Autowired
+    private StateMachine<OrderState, OrderEvent> stateMachine;
+
+    @Override
+    public <S extends IState, T extends IEvent> void sendMessage(T event) {
+        if (event instanceof OrderEvent) {
+            stateMachine.sendEvent(Mono.just(MessageBuilder.withPayload((OrderEvent) event).build())).subscribe();
+        }
+    }
+
+    @Override
+    @Transactional
+    public <S extends IState, T extends IEvent, A extends OutboxAction<T>> void sendMessageWithOutbox(T event, A action) {
+        sendMessage(event);
+
+        if (TransactionSynchronizationManager.isSynchronizationActive()) {
+            TransactionSynchronizationManager.registerSynchronization(new TransactionSynchronization() {
+                @Override
+                public void afterCommit() {
+                    action.onCommit(event);
+                }
+            });
+        } else {
+            action.onCommit(event);
+        }
+    }
+
+    @Override
+    public <T extends OrderEvent> void sendMessageWithProvider(java.util.function.Supplier<T> eventProvider) {
+        T event = eventProvider.get();
+        if (event != null) {
+            stateMachine.sendEvent(Mono.just(MessageBuilder.withPayload((OrderEvent) event).build())).subscribe();
+        }
+    }
+
+    @Override
+    @SafeVarargs
+    public final <T extends IEvent> void sendEventsVarargs(T... events) {
+        // Quirky pattern 2: Iterating over generic varargs
+        for (T event : events) {
+            sendMessage(event);
+        }
+    }
+
+    @Override
+    public <T extends IEvent & java.io.Serializable & Cloneable> T processQuirkyEvent(T event) {
+        // Quirky pattern 3: Multiple bounds, returning the same generic type
+        sendMessage(event);
+        return event; // returns something that is guaranteed to be IEvent, Serializable, AND Cloneable
+    }
+}