Make equals work in DefaultStateMachineContext

- Adding equals and hashCode methods to DefaultStateMachineContext,
  DefaultExtendedState and ObservableMap.
- Fixes #628

spring-statemachine-core/src/main/java/org/springframework/statemachine/support/DefaultExtendedState.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -73,6 +73,36 @@ public class DefaultExtendedState implements ExtendedState {
 		this.listener = listener;
 	}
 
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((variables == null) ? 0 : variables.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj) {
+			return true;
+		}
+		if (obj == null) {
+			return false;
+		}
+		if (getClass() != obj.getClass()) {
+			return false;
+		}
+		DefaultExtendedState other = (DefaultExtendedState) obj;
+		if (variables == null) {
+			if (other.variables != null) {
+				return false;
+			}
+		} else if (!variables.equals(other.variables)) {
+			return false;
+		}
+		return true;
+	}
+
 	@Override
 	public String toString() {
 		return "DefaultExtendedState [variables=" + variables + "]";

spring-statemachine-core/src/main/java/org/springframework/statemachine/support/DefaultStateMachineContext.java

@@ -199,6 +199,92 @@ public class DefaultStateMachineContext<S, E> implements StateMachineContext<S,
 		return extendedState;
 	}
 
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((childRefs == null) ? 0 : childRefs.hashCode());
+		result = prime * result + ((childs == null) ? 0 : childs.hashCode());
+		result = prime * result + ((event == null) ? 0 : event.hashCode());
+		result = prime * result + ((eventHeaders == null) ? 0 : eventHeaders.hashCode());
+		result = prime * result + ((extendedState == null) ? 0 : extendedState.hashCode());
+		result = prime * result + ((historyStates == null) ? 0 : historyStates.hashCode());
+		result = prime * result + ((id == null) ? 0 : id.hashCode());
+		result = prime * result + ((state == null) ? 0 : state.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj) {
+			return true;
+		}
+		if (obj == null) {
+			return false;
+		}
+		if (getClass() != obj.getClass()) {
+			return false;
+		}
+		DefaultStateMachineContext<?, ?> other = (DefaultStateMachineContext<?, ?>) obj;
+		if (childRefs == null) {
+			if (other.childRefs != null) {
+				return false;
+			}
+		} else if (!childRefs.equals(other.childRefs)) {
+			return false;
+		}
+		if (childs == null) {
+			if (other.childs != null) {
+				return false;
+			}
+		} else if (!childs.equals(other.childs)) {
+			return false;
+		}
+		if (event == null) {
+			if (other.event != null) {
+				return false;
+			}
+		} else if (!event.equals(other.event)) {
+			return false;
+		}
+		if (eventHeaders == null) {
+			if (other.eventHeaders != null) {
+				return false;
+			}
+		} else if (!eventHeaders.equals(other.eventHeaders)) {
+			return false;
+		}
+		if (extendedState == null) {
+			if (other.extendedState != null) {
+				return false;
+			}
+		} else if (!extendedState.equals(other.extendedState)) {
+			return false;
+		}
+		if (historyStates == null) {
+			if (other.historyStates != null) {
+				return false;
+			}
+		} else if (!historyStates.equals(other.historyStates)) {
+			return false;
+		}
+		if (id == null) {
+			if (other.id != null) {
+				return false;
+			}
+		} else if (!id.equals(other.id)) {
+			return false;
+		}
+		if (state == null) {
+			if (other.state != null) {
+				return false;
+			}
+		} else if (!state.equals(other.state)) {
+			return false;
+		}
+		return true;
+	}
+
 	@Override
 	public String toString() {
 		return "DefaultStateMachineContext [id=" + id + ", childs=" + childs + ", childRefs=" + childRefs + ", state="

spring-statemachine-core/src/main/java/org/springframework/statemachine/support/ObservableMap.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -164,6 +164,36 @@ public class ObservableMap<K, V> implements Map<K, V> {
 		this.listener = listener;
 	}
 
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((delegate == null) ? 0 : delegate.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj) {
+			return true;
+		}
+		if (obj == null) {
+			return false;
+		}
+		if (getClass() != obj.getClass()) {
+			return false;
+		}
+		ObservableMap<?, ?> other = (ObservableMap<?, ?>) obj;
+		if (delegate == null) {
+			if (other.delegate != null) {
+				return false;
+			}
+		} else if (!delegate.equals(other.delegate)) {
+			return false;
+		}
+		return true;
+	}
+
 	/**
 	 * The listener interface for receiving map change events.
 	 *

spring-statemachine-core/src/test/java/org/springframework/statemachine/support/DefaultStateMachineContextTests.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.statemachine.support;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+import java.util.Arrays;
+import java.util.HashMap;
+
+import org.junit.Test;
+
+public class DefaultStateMachineContextTests {
+
+	@Test
+	public void testEquals() {
+		DefaultStateMachineContext<String, String> c1 = new DefaultStateMachineContext<String, String>(null, null, null,
+				null);
+		DefaultStateMachineContext<String, String> c2 = new DefaultStateMachineContext<String, String>(null, null, null,
+				null);
+		assertThat(c1.equals(c2), is(true));
+
+		DefaultStateMachineContext<String, String> c0 = new DefaultStateMachineContext<String, String>(null, null, null,
+				null);
+
+		c1 = new DefaultStateMachineContext<String, String>(Arrays.asList("x", "y"), Arrays.asList(c0), "s1", "e1",
+				new HashMap<>(), new DefaultExtendedState(), new HashMap<>(), "id");
+		c2 = new DefaultStateMachineContext<String, String>(Arrays.asList("x", "y"), Arrays.asList(c0), "s1", "e1",
+				new HashMap<>(), new DefaultExtendedState(), new HashMap<>(), "id");
+		assertThat(c1.equals(c2), is(true));
+
+		c2 = new DefaultStateMachineContext<String, String>(Arrays.asList("d", "y"), Arrays.asList(c0), "s1", "e1",
+				new HashMap<>(), new DefaultExtendedState(), new HashMap<>(), "id");
+		assertThat(c1.equals(c2), is(false));
+	}
+}