EJB創(chuàng)建應(yīng)用程序
要?jiǎng)?chuàng)建一個(gè)簡(jiǎn)單的EJB模塊，我們將使用NetBeans“新建項(xiàng)目”向?qū)?。在下面的例子中，我們將?chuàng)建一個(gè)名為Component的EJB模塊項(xiàng)目。
創(chuàng)建項(xiàng)目
在NetBeans IDE中，選擇文件>新建項(xiàng)目>（File > New Project >）。你會(huì)看到以下畫(huà)面。
在項(xiàng)目類(lèi)別中選擇項(xiàng)目類(lèi)型，Java EE中 ，項(xiàng)目類(lèi)型為EJB模塊 。單擊下一步>（Next >）按鈕。你會(huì)看到以下畫(huà)面。
輸入項(xiàng)目名稱(chēng)和位置。單擊下一步>（Next >）按鈕。你會(huì)看到以下畫(huà)面。
選擇下圖中選項(xiàng)作為JBoss應(yīng)用服務(wù)器 。單擊Finish按鈕。你會(huì)看到NetBeans中創(chuàng)建以下項(xiàng)目。
創(chuàng)建示例EJB
要?jiǎng)?chuàng)建一個(gè)簡(jiǎn)單的EJB，我們將使用NetBeans“新建”向?qū)АＴ谙旅娴睦又?，我們將?chuàng)建EjbComponent項(xiàng)目名為librarySessionBean的一個(gè)無(wú)狀態(tài)的EJB類(lèi)。
選擇項(xiàng)目EjbComponent在項(xiàng)目資源管理器窗口，并在其上單擊右鍵。選擇New > Session Bean
，即可看到新的Bean向?qū)?/span>會(huì)話(huà)。
輸入會(huì)話(huà)bean名稱(chēng)和包名稱(chēng)。單擊Finish按鈕。你會(huì)看到NetBeans中創(chuàng)建以下EJB類(lèi)。
LibrarySessionBean -無(wú)狀態(tài)會(huì)話(huà)bean
LibrarySessionBeanLocal -本地接口的會(huì)話(huà)bean
我改變本地接口的遠(yuǎn)程接口，我們要訪(fǎng)問(wèn)我們的EJB在控制臺(tái)基礎(chǔ)的應(yīng)用。遠(yuǎn)程/本地接口用于公開(kāi)，一個(gè)EJB必須實(shí)現(xiàn)業(yè)務(wù)方法。
LibrarySessionBeanLocal被重命名為L(zhǎng)ibrarySessionBeanRemote和LibrarySessionBean實(shí)現(xiàn)LibrarySessionBeanRemote接口。
LibrarySessionBeanRemote
package com.tutorialspoint.stateless;
import java.util.List;
import javax.ejb.Remote;
@Remote
public interface LibrarySessionBeanRemote {
void addBook(String bookName);
List getBooks();
}
LibrarySessionBean
package com.tutorialspoint.stateless;
import java.util.ArrayList;
import java.util.List;
import javax.ejb.Stateless;
@Stateless
public class LibrarySessionBean implements LibrarySessionBeanRemote {
List<String> bookShelf;
public LibrarySessionBean(){
bookShelf = new ArrayList<String>();
}
public void addBook(String bookName) {
bookShelf.add(bookName);
}
public List<String> getBooks() {
return bookShelf;
}
}
建設(shè)項(xiàng)目
在項(xiàng)目資源管理器窗口中選擇Ejb組件（Component）項(xiàng)目
右鍵點(diǎn)擊它，打開(kāi)上下文菜單。
選擇清理并生成。
你會(huì)看到在NetBeans控制臺(tái)輸出以下輸出。
ant -f C:EJBEjbComponent clean dist init: undeploy-clean: deps-clean: Deleting directory C:EJBEjbComponentuild Deleting directory C:EJBEjbComponentdist clean: init: deps-jar: Created dir: C:EJBEjbComponentuildclasses Copying 3 files to C:EJBEjbComponentuildclassesMETA-INF Created dir: C:EJBEjbComponentuildempty Created dir: C:EJBEjbComponentuildgenerated-sourcesap-source-output Compiling 2 source files to C:EJBEjbComponentuildclasses warning: [options] bootstrap class path not set in conjunction with -source 1.6 Note: C:EJBEjbComponentsrcjavacom utorialspointstateless LibraryPersistentBean.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details. 1 warning compile: library-inclusion-in-archive: Created dir: C:EJBEjbComponentdist Building jar: C:EJBEjbComponentdistEjbComponent.jar dist: BUILD SUCCESSFUL (total time: 3 seconds)
啟動(dòng)應(yīng)用服務(wù)器
在服務(wù)窗口服務(wù)器下選擇JBoss應(yīng)用服務(wù)器
右鍵點(diǎn)擊它，打開(kāi)上下文菜單。
選擇啟動(dòng)。
你會(huì)看到在NetBeans下JBoss應(yīng)用服務(wù)器下面的輸出，輸出。
Calling C:jboss-5.1.0.GAin un.conf.bat ========================================================================= JBoss Bootstrap Environment JBOSS_HOME: C:jboss-5.1.0.GA JAVA: C:Program Files (x86)Javajdk1.6.0_21injava JAVA_OPTS: -Dprogram.name=run.bat -Xms128m -Xmx512m -server CLASSPATH: C:jboss-5.1.0.GAin un.jar ========================================================================= 16:25:50,062 INFO [ServerImpl] Starting JBoss (Microcontainer)... 16:25:50,062 INFO [ServerImpl] Release ID: JBoss [The Oracle] 5.1.0.GA (build: SVNTag=JBoss_5_1_0_GA date=200905221634) ... 16:26:40,420 INFO [TomcatDeployment] deploy, ctxPath=/admin-console 16:26:40,485 INFO [config] Initializing Mojarra (1.2_12-b01-FCS) for context '/admin-console' 16:26:42,362 INFO [TomcatDeployment] deploy, ctxPath=/ 16:26:42,406 INFO [TomcatDeployment] deploy, ctxPath=/jmx-console 16:26:42,471 INFO [Http11Protocol] Starting Coyote HTTP/1.1 on http-127.0.0.1-8080 16:26:42,487 INFO [AjpProtocol] Starting Coyote AJP/1.3 on ajp-127.0.0.1-8009 16:26:42,493 INFO [ServerImpl] JBoss (Microcontainer) [5.1.0.GA (build: SVNTag=JBoss_5_1_0_GA date=200905221634)] Started in 52s:427ms
部署項(xiàng)目
在項(xiàng)目資源管理器窗口中選擇Ejb組件（Component）項(xiàng)目
右鍵點(diǎn)擊它，打開(kāi)上下文菜單。
選擇部署。
你會(huì)看到在NetBeans控制臺(tái)輸出以下輸出。
ant -f C:EJBEjbComponent -DforceRedeploy=true -Ddirectory.deployment.supported=false -Dnb.wait.for.caches=true run init: deps-jar: compile: library-inclusion-in-archive: Building jar: C:EJBEjbComponentdistEjbComponent.jar dist-directory-deploy: pre-run-deploy: Checking data source definitions for missing JDBC drivers... Distributing C:EJBEjbComponentdistEjbComponent.jar to [org.jboss.deployment.spi.LocalhostTarget@1e4f84ee] Deploying C:EJBEjbComponentdistEjbComponent.jar Applicaton Deployed Operation start started Operation start completed post-run-deploy: run-deploy: run: BUILD SUCCESSFUL (total time: 2 seconds)
JBoss應(yīng)用服務(wù)器的日志輸出
16:30:00,963 INFO [DeployHandler] Begin start, [EjbComponent.jar]
...
16:30:01,233 INFO [Ejb3DependenciesDeployer] Encountered deployment AbstractVFSDeploymentContext@12038795{vfszip:/C:/jboss-5.1.0.GA/server/default/deploy/EjbComponent.jar/}
...
16:30:01,281 INFO [JBossASKernel] jndi:LibrarySessionBean/remote-com.tutorialspoint.stateless.LibrarySessionBeanRemote
16:30:01,281 INFO [JBossASKernel] Class:com.tutorialspoint.stateless.LibrarySessionBeanRemote
16:30:01,281 INFO [JBossASKernel] jndi:LibrarySessionBean/remote
16:30:01,281 INFO [JBossASKernel] Added bean(jboss.j2ee:jar=EjbComponent.jar,name=
LibrarySessionBean,service=EJB3) to KernelDeployment of: EjbComponent.jar
16:30:01,282 INFO [JBossASKernel] installing bean: jboss.j2ee:jar=EjbComponent.jar,name=BookMessageHandler,service=EJB3
16:30:01,282 INFO [JBossASKernel] with dependencies:
16:30:01,282 INFO [JBossASKernel] and demands:
16:30:01,282 INFO [JBossASKernel] jboss.ejb:service=EJBTimerService
...
16:30:01,283 INFO [EJB3EndpointDeployer] Deploy AbstractBeanMetaData@5497cb{name=jboss.j2ee:jar=EjbComponent.jar, name=LibrarySessionBean, service=EJB3_endpoint bean=org.jboss.ejb3.endpoint.deployers.impl.EndpointImpl properties=[container] constructor=null autowireCandidate=true}
...
16:30:01,394 INFO [SessionSpecContainer] Starting jboss.j2ee:jar=EjbComponent.jar,name=LibrarySessionBean,service=EJB3
16:30:01,395 INFO [EJBContainer] STARTED EJB: com.tutorialspoint.stateless.LibrarySessionBean ejbName: LibrarySessionBean
16:30:01,401 INFO [JndiSessionRegistrarBase] Binding the following Entries in Global JNDI:
LibrarySessionBean/remote - EJB3.x Default Remote Business Interface
LibrarySessionBean/remote-com.tutorialspoint.stateless.LibrarySessionBeanRemote - EJB3.x Remote Business Interface
16:30:02,723 INFO [SessionSpecContainer] Starting jboss.j2ee:jar=EjbComponent.jar,name=LibrarySessionBean,service=EJB3
16:30:02,723 INFO [EJBContainer] STARTED EJB: com.tutorialspoint.stateless.LibrarySessionBean ejbName: LibrarySessionBean
16:30:02,731 INFO [JndiSessionRegistrarBase] Binding the following Entries in Global JNDI:
LibrarySessionBean/remote - EJB3.x Default Remote Business Interface
LibrarySessionBean/remote-com.tutorialspoint.stateless.LibrarySessionBeanRemote - EJB3.x Remote Business Interface
創(chuàng)建客戶(hù)端訪(fǎng)問(wèn)EJB
在NetBeans IDE中，選擇文件>新建項(xiàng)目>（File > New Project >）。
在類(lèi)別中選擇項(xiàng)目類(lèi)型，Java ，項(xiàng)目類(lèi)型為Java應(yīng)用程序 。單擊下一步>（Next >）按鈕。
輸入項(xiàng)目名稱(chēng)和位置。單擊Finish>按鈕。我們選擇的名稱(chēng)為EjbTester。
右鍵點(diǎn)擊Project Explorer窗口中的項(xiàng)目名稱(chēng)。選擇屬性（properties） 。
在早先創(chuàng)建EJB組件項(xiàng)目中添加使用編譯選項(xiàng)的添加項(xiàng)目按鈕。
使用編譯選項(xiàng)中添加JAR /文件夾按鈕添加的JBoss庫(kù)。 Jboss的庫(kù)可以位于<JBoss安裝文件夾>>客戶(hù)端文件夾。
在EjbTester中創(chuàng)建文件名為jndi.properties的項(xiàng)目。
jndi.properties
java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory java.naming.factory.url.pkgs=org.jboss.naming:org.jnp.interfaces java.naming.provider.url=localhost
其下創(chuàng)建包c(diǎn)om.tutorialspoint.test和EJBTester.java類(lèi)。
EJBTester.java
package com.tutorialspoint.test;
import com.tutorialspoint.stateless.LibrarySessionBeanRemote;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.List;
import java.util.Properties;
import javax.naming.InitialContext;
import javax.naming.NamingException;
public class EJBTester {
BufferedReader brConsoleReader = null;
Properties props;
InitialContext ctx;
{
props = new Properties();
try {
props.load(new FileInputStream("jndi.properties"));
} catch (IOException ex) {
ex.printStackTrace();
}
try {
ctx = new InitialContext(props);
} catch (NamingException ex) {
ex.printStackTrace();
}
brConsoleReader =
new BufferedReader(new InputStreamReader(System.in));
}
public static void main(String[] args) {
EJBTester ejbTester = new EJBTester();
ejbTester.testStatelessEjb();
}
private void showGUI(){
System.out.println("**********************");
System.out.println("Welcome to Book Store");
System.out.println("**********************");
System.out.print("Options
1. Add Book
2. Exit
Enter Choice: ");
}
private void testStatelessEjb(){
try {
int choice = 1;
LibrarySessionBeanRemote libraryBean =
(LibrarySessionBeanRemote)ctx.lookup("LibrarySessionBean/remote");
while (choice != 2) {
String bookName;
showGUI();
String strChoice = brConsoleReader.readLine();
choice = Integer.parseInt(strChoice);
if (choice == 1) {
System.out.print("Enter book name: ");
bookName = brConsoleReader.readLine();
libraryBean.addBook(bookName);
}else if (choice == 2) {
break;
}
}
List<String> booksList = libraryBean.getBooks();
System.out.println("Book(s) entered so far: " + booksList.size());
for (int i = 0; i < booksList.size(); ++i) {
System.out.println((i+1)+". " + booksList.get(i));
}
LibrarySessionBeanRemote libraryBean1 =
(LibrarySessionBeanRemote)ctx.lookup("LibrarySessionBean/remote");
List<String> booksList1 = libraryBean1.getBooks();
System.out.println(
"***Using second lookup to get library stateless object***");
System.out.println(
"Book(s) entered so far: " + booksList1.size());
for (int i = 0; i < booksList1.size(); ++i) {
System.out.println((i+1)+". " + booksList1.get(i));
}
} catch (Exception e) {
System.out.println(e.getMessage());
e.printStackTrace();
}finally {
try {
if(brConsoleReader !=null){
brConsoleReader.close();
}
} catch (IOException ex) {
System.out.println(ex.getMessage());
}
}
}
}
運(yùn)行客戶(hù)端訪(fǎng)問(wèn)EJB
在項(xiàng)目資源管理器中找到EJBTester.java。右鍵單擊EJBTester類(lèi)并選擇運(yùn)行文件 。
驗(yàn)證Netbeans控制臺(tái)下面的輸出。
run: ********************** Welcome to Book Store ********************** Options 1. Add Book 2. Exit Enter Choice: 1 Enter book name: Learn Java ********************** Welcome to Book Store ********************** Options 1. Add Book 2. Exit Enter Choice: 2 Book(s) entered so far: 1 1. Learn Java ***Using second lookup to get library stateless object*** Book(s) entered so far: 0 BUILD SUCCESSFUL (total time: 13 seconds)
在下面的章節(jié)中，我們將討論這個(gè)完整的EJB應(yīng)用程序的多個(gè)方面。
更多建議：