11.扩大ejb的功效.pptVIP

扩充EJB组件的功能;;在线书店;用户注册;用户登录;在线购书;查看订单;结帐;EJB组件间调用-1.默认的JNDI查找;;;EJB组件间调用-2.Annotation;EJB组件间调用-3.@Resource;公用注释;@Stateful(mappedName=ejb/TR) public class TaxRateBean implements TaxRate { public double getTaxRate(String state) { if (state.equalsIgnoreCase(ny)) { return 0.0875; } else if (state.equalsIgnoreCase(nj)) { return 0.03; } else { return 0.0; } } };mappedName;将@EJB作用于类级 @EJB(name=ejb/TR, beanInterface=TaxRate.class) @Stateless public class PricerBean implements Pricer{ TaxRate taxRate = (TaxRate)ic.lookup (java:comp/env/ejb/TR); 。。。。。。 } 这是和容器无关的JNDI绑定。 ;@Stateless(name=ejb/TR) public class TaxRateBean implements TaxRate { public double getTaxRate(String state) { if (state.equalsIgnoreCase(ny)) { return 0.0875; } else if (state.equalsIgnoreCase(nj)) { return 0.03; } else { return 0.0; } } };;% Context ctx=null; ctx=new InitialContext(); p2.Pricer pricer=(p2.Pricer)ctx.lookup( Pricer.class.getName()); pricer.doIt(); %;@EJB（ name=“ejb/pricer” beanName=“pricer” ） private Pricer pricer; beanName不能在bean类上注释，只能借助于部署描述符文件;@Stateless(name=HelloWorld, mappedName=HelloBean) @Remote(HelloWorldRemoteManager.class) public class HelloWorldRemoteBean implements HelloWorldRemoteManager{…} 对于每个引用者而言，需要如下定义EJB引用： @EJB(name=HelloWorld, mappedName=HelloBean) HelloWorldRemoteManager helloWorld; ;依赖注入;;资源引用示例; private DataSource _TimePool; private DataSource sample_pm; @Resource SessionContext sctx; @Resource(name=“timeout”) long timeout; @Resource (name=“jdbc/_TimerPool”) private void set_TimerPool(DataSource ds){ _TimerPool=ds; } @PostConstruct(){ sample_pm=(DataSource)sctx.lookup(“jdbc/sample”); } public long getTimeout(){ return timeout; };