BAEL - 717 : Singleton EJB Beans. (#3883)

* BAEL-717: Singleton EJB Bean Files for BAEL-717:Singleton EJB Bean. * BAEL-717: Singleton EJB Bean Corrected Indentation. * BAEL-717: Singleton EJB Bean Corrected Indentation. * BAEL-717: Singleton EJB Bean Corrected Indentation. * BAEL-717: Singleton EJB Bean Corrected Indentation. * BAEL-717: Singleton EJB Bean Changed artifactId value. * BAEL-717: Singleton EJB Bean. Added module for Singleton EJB Bean. * BAEL-717: Singleton EJB Bean. Removed Singleton EJB Bean Module. * BAEL-717: Singleton EJB Bean Changed the JNDI Lookup name. * BAEL-717: Singleton EJB Bean. Added the "singleton-ejb-bean" module. * BAEL-717: Singleton EJB Bean. Corrected Indentation. * BAEL-717: Singleton EJB Bean Corrected Indentation. * BAEL-717: Singleton EJB Bean. Corrected Indentation. * BAEL-717: Singleton EJB Bean. Corrected Indentation. * BAEL-717:Singleton EJB Bean. Corrected Indentation. * BAEL-717:Singleton EJB Bean. Corrected Indentation.
2018-03-28 07:35:53 -05:00
parent de06e4f6be
commit 757f634467
5 changed files with 140 additions and 0 deletions
@@ -0,0 +1,12 @@
+package com.baeldung.singletonbean;
+
+import java.util.List;
+
+import javax.ejb.Local;
+
+@Local
+public interface CountryState {
+
+    public List<String> getStates(String country);
+
+}
@@ -0,0 +1,41 @@
+package com.baeldung.singletonbean;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import javax.annotation.PostConstruct;
+import javax.ejb.ConcurrencyManagement;
+import javax.ejb.ConcurrencyManagementType;
+import javax.ejb.Lock;
+import javax.ejb.LockType;
+import javax.ejb.Singleton;
+import javax.ejb.Startup;
+
+@Singleton
+@Startup
+@ConcurrencyManagement(ConcurrencyManagementType.CONTAINER)
+public class CountryStateCacheBean implements CountryState {
+
+    private Map<String, List<String>> countryStatesMap = new HashMap<String, List<String>>();
+
+    @Lock(LockType.WRITE)
+    @PostConstruct
+    public void initialize() {
+
+        List<String> states = new ArrayList<String>();
+        states.add("Texas");
+        states.add("Alabama");
+        states.add("Alaska");
+        states.add("Arizona");
+        states.add("Arkansas");
+
+        countryStatesMap.put("UnitedStates", states);
+    }
+
+    @Lock(LockType.READ)
+    public List<String> getStates(String country) {
+        return countryStatesMap.get(country);
+    }
+}
@@ -0,0 +1,46 @@
+package com.baeldung.singletonbean;
+
+import static org.junit.Assert.assertArrayEquals;
+
+import java.util.List;
+
+import javax.ejb.embeddable.EJBContainer;
+import javax.naming.Context;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.baeldung.singletonbean.CountryState;
+
+public class CountryStateCacheBeanTest {
+
+    private EJBContainer ejbContainer = null;
+
+    private Context context = null;
+
+    @Before
+    public void init() {
+
+        ejbContainer = EJBContainer.createEJBContainer();
+        context = ejbContainer.getContext();
+    }
+
+    @Test
+    public void whenCallGetStates_ReturnsStatesForCountry() throws Exception {
+
+        String[] actualStates = { "Texas", "Alabama", "Alaska", "Arizona", "Arkansas" };
+
+        CountryState countryStateBean = (CountryState) context.lookup("java:global/singleton-ejb-bean/CountryStateCacheBean");
+        List<String> states = countryStateBean.getStates("UnitedStates");
+        if (states != null) {
+            assertArrayEquals(states.toArray(), actualStates);
+        }
+    }
+
+    @After
+    public void close() {
+        if (ejbContainer != null)
+            ejbContainer.close();
+    }
+}