ejb

可能的面试问题及答案

不羁的心 提交于 2020-03-16 08:34:19
有感 : 应聘 Java 笔试时可能出现问题及其答案 huij 前段时间因为要参加一个笔试,在准备期间在网上找到了两条关于笔试题目的文章,其中一篇为<<有感:应聘Java笔试时可能出现问题>>,还有一篇忘了名字,读后深受启发。 在寻找这些答案的过程中,我将相关答案记录下来,就形成了以下这些东西。需要说明的是以下答案肯定有很多不完整甚至错误的地方,需要各位来更正与完善它,千万不要扔我的鸡蛋啊。 希望本文能够给即将奔赴笔试考场的同仁些许帮助,更希望更多的人加入到收集整理笔试题与完善答案的这些工作中来,为大家更好的获得工作机会做一点贡献。 在此感谢前面两文的作者的对笔试题目的收集与整理。 如有任何意见与建议请通过QQ:6045306,Mail:huijunzi@21cn.com与我联系。 Java基础方面: 1、作用域public,private,protected,以及不写时的区别 答:区别如下: 作用域 当前类 同一package 子孙类 其他package public √ √ √ √ protected √ √ √ × friendly √ √ × × private √ × × × 不写时默认为friendly 2、ArrayList和Vector的区别,HashMap和Hashtable的区别 答:就ArrayList与Vector主要从二方面来说. 一.同步性

weblogic详解

走远了吗. 提交于 2020-03-16 02:00:25
转自:https://www.cnblogs.com/telwanggs/p/7137116.html 一、简介 WebLogic是美国 Oracle 公司出品的一个application server,确切的说是一个基于JAVAEE 架构 的中间件,WebLogic是用于开发、集成、部署和管理大型分布式Web应用、网络应用和 数据库 应用的 Java 应用服务器。将Java的动态功能和 Java Enterprise标准的安全性引入大型网络应用的开发、集成、部署和管理之中。 WebLogic是美商 oracle 的主要产品之一,系并购BEA得来。是商业市场上主要的Java(J2EE)应用服务器软件(application server)之一,是世界上第一个成功商业化的J2EE应用服务器, 已推出到12c(12.1.3) 版。而此产品也延伸出WebLogic Portal,WebLogic Integration等企业用的中间件(但当下Oracle主要以Fusion Middleware融合中间件来取代这些WebLogic Server之外的企业包),以及OEPE(Oracle Enterprise Pack for Eclipse)开发工具。(来自百度百科) 官方文档地址: http://docs.oracle.com/en/middleware/index.html 二、优点

Java Web整合开发(80) -- EJB & WebService

你说的曾经没有我的故事 提交于 2020-03-14 00:32:41
1. jdk-6u18-windows-i586-p.exe classpath: .;%JAVA_HOME%lib/tools.jar;%JAVA_HOME%lib/dt.jar;%JAVA_HOME%bin 其中JAVA_HOME代表JDK(不是JRE)的安装路径 2. java_ee_sdk-5_08-windows-ml-nojdk.exe classpath: .;D:\Sun\SDK\lib\javaee.jar http://java.sun.com/javaee 3. JBoss5.1.0.GA,直接解压缩 http://www.jboss.org/jbossas 4. WebLogic 11g (10.3.2) http://www.oracle.com/technetwork/middleware/weblogic/downloads/wls-for-dev-1703574.html 5. apache-ant-1.7.1, 解压到任意路径,增加ANT_HOME为解压路径。PATH: %ANT_HOME%/bin http://ant.apache.org 6. MySQL 5.1或更高版本 7. NetBeans6.8 http://netbeans.org 8. SVN http://subversion.tigris.org/servlets

EntityManager is null when use in parallelStream

感情迁移 提交于 2020-03-06 09:43:13
问题 I have an EJB bean which have a method that call another method from the bean with parallel stream. It works fine, but in the async method I must update entity in the db and when I call entityManager.merge than I got a NullPointerExpcetion. I don't know why. I use OpenJPA on WebSphere. The original question was: Call a method for List in parallel? @Stateless public class TestBean implements LocalInterface, RemoterInterface { @PersistenceContext(unitName = Constants.PERSISTENCE_UNIT) protected

Jboss use JTS instead of JTA

巧了我就是萌 提交于 2020-03-05 01:34:27
问题 I have jacorb subsystem enabled in my jboss. But JTS is not enabled, I use only JTA. When an EJB remote call received by the jboss, instead of using JTA(com.arjuna.ats.internal.jta.transaction.arjunacore.jca.TransactionImporterImple) it gets JTS(com.arjuna.ats.internal.jta.transaction.jts.jca.TransactionImporterImple) and proceed with JTS. Since JTS is not enabled it failed with ORB is not initialized error. Can you please help me to identify why JTS is used instead of JTA. JBAS014134: EJB

Jboss use JTS instead of JTA

好久不见. 提交于 2020-03-05 01:34:07
问题 I have jacorb subsystem enabled in my jboss. But JTS is not enabled, I use only JTA. When an EJB remote call received by the jboss, instead of using JTA(com.arjuna.ats.internal.jta.transaction.arjunacore.jca.TransactionImporterImple) it gets JTS(com.arjuna.ats.internal.jta.transaction.jts.jca.TransactionImporterImple) and proceed with JTS. Since JTS is not enabled it failed with ORB is not initialized error. Can you please help me to identify why JTS is used instead of JTA. JBAS014134: EJB

How to serialize an injected bean?

╄→尐↘猪︶ㄣ 提交于 2020-02-25 23:35:12
问题 I would like to save the data of an injected stateful bean at various intervals: change - save - change- save... I'm using core serialization and the problem is that all the byte arrays are the same. i believe the proxy is serialized because if I deserialize one of the arrays later I get the current state of the bean. Example of serialization not capturing changes in the bean: @Stateful @RequestScoped public class State implements Serializable { private static final long serialVersionUID = 1L

glassfish: while deploying the app IOException: invalid zip file

妖精的绣舞 提交于 2020-02-15 10:10:14
问题 In deploying the EAR through the CLI, this error occurs: Exception while deploying the app [EnterpriseLegacy] : java.io.IOException: invalid zip file: file:/home/thufir/glassfish-4.1/glassfish/domains/domain1/application /EnterpriseLegacy/lib/RemoteEJB.jar and yet, Netbeans deploys the same EAR fine from within the IDE. I think the problem is that the EJB module depends on a remote interface, RemoteEJB which builds as a JAR. This JAR is included with the EAR, but I don't believe that's

从进一步了解Java开始

坚强是说给别人听的谎言 提交于 2020-02-12 11:39:04
Java2平台三个版本: 1.J2SE(Java Standard Edition标准版)用于开发桌面应用程序 2.J2EE(Java Enterprise Edition企业版)用于开发分布式网络程序,如电子商务网站和ERP系统 3.J2ME(Java Micro Edition微缩版)主要用于嵌入式开发,如手机和PDA的编程 J2SE是基础; 压缩一点,再增加一些CLDC等方面的特性就是J2ME; 扩充一点,再增加一些EJB等企业应用方面的特性就是J2EE。 J2EE是JAVA2企业开发的技术规范,它不仅仅是比标准版多了一些类 又包括许多组件,如Jsp,Servlet,JavaBean,EJB,JDBC,JavaMail等。 来源: https://www.cnblogs.com/onemorestep/p/12293065.html

Plug Bean to JBoss with JNDI

可紊 提交于 2020-02-06 16:37:37
问题 I wonder how object (if it matter I need EJB) can be plugged to JBoss (5.0) with JNDI? I have following bean definition in my Spring applicationContext.xml : <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager"> <property name="entityManagerFactory" ref="entityManagerFactory" /> </bean> <tx:annotation-driven transaction-manager="transactionManager" /> <context:annotation-config/> <bean id="myServiceFacade" class="org.springframework.jndi