My implementation

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "git.ignoreLimitWarning": true
+}

bin/.gitignore

@@ -0,0 +1,4 @@
+target/
+.settings/
+.classpath
+.project

bin/.travis.yml

@@ -0,0 +1 @@
+language: java

bin/pom.xml

@@ -0,0 +1,40 @@
+<?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>
+
+  <groupId>kz.edu.nu.cs</groupId>
+  <artifactId>stateexercise-361</artifactId>
+  <version>0.0.1-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <name>stateexercise-361</name>
+  <url>http://maven.apache.org</url>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>4.12</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+  <pluginManagement>
+   <plugins>
+    <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <configuration>
+            <source>1.8</source>
+            <target>1.8</target>
+        </configuration>
+    </plugin>
+  </plugins>
+  </pluginManagement>
+  </build>
+</project>

src/main/java/kz/edu/nu/cs/exercise/State1.java

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+package kz.edu.nu.cs.exercise;
+
+public class State1 extends State {
+
+	public State1(StateContext stateContext) {
+		// TODO Auto-generated constructor stub
+		this.sc = stateContext;
+	}
+
+	public void actionA() {
+
+		this.sc.setCurrentState(sc.state2);
+	}
+
+	public void actionB() {
+
+		this.sc.setCurrentState(sc.state1);
+
+	}
+
+	public boolean inAcceptState() {
+
+		return false;
+	}
+
+}

src/main/java/kz/edu/nu/cs/exercise/State2.java

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+package kz.edu.nu.cs.exercise;
+
+public class State2 extends State {
+
+	public State2(StateContext stateContext) {
+		// TODO Auto-generated constructor stub
+		this.sc = stateContext;
+	}
+
+	public void actionA() {
+
+		this.sc.setCurrentState(sc.state3);
+	}
+
+	public void actionB() {
+
+		this.sc.setCurrentState(sc.state1);
+
+	}
+
+	public boolean inAcceptState() {
+
+		return false;
+	}
+
+}

src/main/java/kz/edu/nu/cs/exercise/State3.java

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+package kz.edu.nu.cs.exercise;
+
+public class State3 extends State {
+
+	public State3(StateContext stateContext) {
+		// TODO Auto-generated constructor stub
+		this.sc = stateContext;
+	}
+
+	public void actionA() {
+
+		this.sc.setCurrentState(sc.state3);
+	}
+
+	public void actionB() {
+
+		this.sc.setCurrentState(sc.state2);
+
+	}
+
+	public boolean inAcceptState() {
+
+		return true;
+	}
+
+}

src/main/java/kz/edu/nu/cs/exercise/StateContext.java

@@ -1,38 +1,43 @@
 package kz.edu.nu.cs.exercise;
 
 public class StateContext {
-    final State state1 = new State1(this);
-    final State state2 = new State2(this);
-    final State state3 = new State3(this);
-
-    private State currentState;
-
-    public StateContext() {
-        this.currentState = state1;
-    }
-
-    public void actionA() {
-        // complete this method by
-        // delegation to the current state
-    }
-
-    public void actionB() {
-        // complete this method
-        // delegate to the current state
-    }
-
-    public boolean inAcceptState() {
-        // complete this method and return correct value
-        // delegate to the current state
-        return false;
-    }
-
-    public State getCurrentState() {
-        return currentState;
-    }
-
-    public void setCurrentState(State currentState) {
-        this.currentState = currentState;
-    }
+	final State state1 = new State1(this);
+	final State state2 = new State2(this);
+	final State state3 = new State3(this);
+
+	private State currentState;
+
+	public StateContext() {
+		this.currentState = state1;
+	}
+
+	public void actionA() {
+		// complete this method by
+		// delegation to the current state
+		this.currentState.actionA();
+
+	}
+
+	public void actionB() {
+		// complete this method
+		// delegate to the current state
+		this.currentState.actionB();
+
+	}
+
+	public boolean inAcceptState() {
+		if(this.currentState == state3) {return true;}
+		// complete this method and return correct value
+		// delegate to the current state
+		return false;
+	}
+
+	public State getCurrentState() {
+		return currentState;
+	}
+
+	public void setCurrentState(State currentState) {
+		this.currentState = currentState;
+	}
 
 }