EJB Tutorial from JBoss: Injection
File: CalculatorBean.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.injection.bean; import javax.ejb.Stateless; @Stateless public class CalculatorBean implements Calculator { public int add(int x, int y) { return x + y; } public int subtract(int x, int y) { return x - y; } } File: ShoppingCart.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.injection.bean; import java.util.HashMap; import javax.ejb.Remove; public interface ShoppingCart { void buy(String product, int quantity); HashMap<String, Integer> getCartContents(); @Remove void checkout(); } File: ShoppingCartBean.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.injection.bean; import java.util.HashMap; import javax.ejb.EJB; import javax.ejb.Remote; import javax.ejb.Remove; import javax.ejb.Stateful; @Stateful @Remote(ShoppingCart.class) public class ShoppingCartBean implements ShoppingCart, java.io.Serializable { private HashMap<String, Integer> cart = new HashMap<String, Integer>(); @EJB private Calculator calculator; private Calculator set; @EJB(beanName="CalculatorBean") public void setCalculator(Calculator c) { set = c; } public void buy(String product, int quantity) { if (cart.containsKey(product)) { int currq = cart.get(product); currq = calculator.add(currq, quantity); cart.put(product, currq); } else { cart.put(product, quantity); } } public HashMap<String, Integer> getCartContents() { return cart; } @Remove public void checkout() { System.out.println("To be implemented"); } } File: Calculator.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.injection.bean; public interface Calculator { int add(int x, int y); int subtract(int x, int y); } File: Client.java /* * JBoss, Home of Professional Open Source. * Copyright 2006, Red Hat Middleware LLC, and individual contributors * as indicated by the @author tags. See the copyright.txt file in the * distribution for a full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jboss.tutorial.injection.client; import org.jboss.tutorial.injection.bean.ShoppingCart; import javax.naming.InitialContext; import java.util.HashMap; /** * Comment * * @author <a href="mailto:bill@jboss.org">Bill Burke</a> * @version $Revision: 57207 $ */ public class Client { public static void main(String[] args) throws Exception { InitialContext ctx = new InitialContext(); ShoppingCart cart = (ShoppingCart) ctx.lookup("ShoppingCartBean/remote"); System.out.println("Buying 1 memory stick"); cart.buy("Memory stick", 1); System.out.println("Buying another memory stick"); cart.buy("Memory stick", 1); System.out.println("Buying a laptop"); cart.buy("Laptop", 1); System.out.println("Print cart:"); HashMap<String, Integer> fullCart = cart.getCartContents(); for (String product : fullCart.keySet()) { System.out.println(fullCart.get(product) + " " + product); } System.out.println("Checkout"); cart.checkout(); } }
1. | Field Injection | ![]() | |
2. | Setter Injection | ![]() | |
3. | Use Injected Context To Loopup An other EJB | ![]() | |
4. | Inject Transaction As Resource | ![]() | |
5. | Use EJB To Reference Another EJB In One EJB | ![]() |