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  85 FUJITSU Sci. Tech. J., 40 ,1,p.85-93 (  June 2004 ) Latest Progress and Trends in Java/EJBTechnologies V Sumio Tasaka V Jun Ginbayashi (Manuscript received February 2, 2004) Java is evolving into a full-scale system development technology by the addition offunctions such as Applets, object-oriented programming, cross-platform support,internationalization, JavaBeans, Remote Method Invocation (RMI), Java Database Con-nectivity (JDBC), Enterprise JavaBeans (EJB), Java Plug-in, HotSpot Client VirtualMachine (VM), Java Naming and Directory Interface (JNDI), RMI/Internet Inter-ORB Pro-tocol (IIOP), eXtensible Mark-up Language (XML) support, and Java Secure SocketExtension (JSSE). These functions have been added in three specifications: Java 2Platform, Enterprise Edition (J2EE); Java 2 Platform, Standard Edition (J2SE); andJava 2 Platform, Micro Edition (J2ME). Also, the manner in which these specificationsare decided has shifted from decisions made by Sun Microsystems to decisions madeby an open community through a process called the Java Community Process (JCP).The main key-phrase of the latest trend in Java/EJB is “Ease of Development,” andJ2SE 1.5 (code name “Tiger”) will play a central role in this trend. Prospectiveenhancements in the Java programming language specifications such as Generics,Enhanced for Loop, Autoboxing/Unboxing, Typesafe Enums, Varargs, Static Import,and Metadata are expected to simplify system development, learning, and mastering.With these new technologies, Java will be used by a wider range of developers andEJB-based development of enterprise systems will become more popular. 1.Introduction Since its appearance in 1995, Java technolo-gy (including Enterprise JavaBeans [EJB]) hasbeen evolving with various functions towards atechnology for full-scale system development.Frequent enhancements with these functions haveled to a wider Java application area. However,these enhancements have raised applicationdevelopers’ feelings of insecurity about the stabil-ity of Java and forced them to spend more timelearning and mastering Java.This paper aims to eliminate unnecessaryanxiety among developers by looking back on thehistory of Java/EJB technology and clearly show-ing its future trend.First, in Section 2, the history so far of Java/EJB technology is summarized. Section 3 showsthe direction of future enhancements in Java/EJB,mainly based on the themes that are currentlybeing discussed in the Java Community Process(JCP). In Section 4, the details of the latest ver-sion (Java 2 Platform, Standard Edition [J2SE]1.5), whose outline has just become clear, are in-troduced. Finally, Section 5 concludes with a brieflook at the future of Java/EJB. 2.History and current status ofJava Java was introduced by Sun Microsystemsin 1995 together with a browser, HotJava. Then,Java gained public attention in the form of Ap-plets, which are programs running on a browser,and was later expanded to include, for example,server-side applications and mobile appliances.  86 FUJITSU Sci. Tech. J., 40 ,1, (  June 2004 ) S. Tasaka et al.: Latest Progress and Trends in Java/EJB Technologies  The major version upgrades of Java areshown in Table 1 .The major enhancement points of each ver-sion are given below.1)Version 1.0Java Development Kit (JDK) 1.0 was an-nounced as the first release of Java with thefollowing features:ãObject orientationãCross-platform supportãNetwork compatibilityBecause it was a C++-like language, and alsobecause of its simple and pure language specifi-cations, Java was quickly and warmly acceptedby developers, which is unusual for a new lan-guage. However, it did not have sufficientfunctions for system development. Also, it wasdifficult to use Java in a Japanese environment,because internationalization was not supported.2)Version 1.1Approximately one year later, JDK 1.1 wasannounced. The following functions were addedin JDK 1.1:ãInternationalizationãJavaBeansãRemote Method Invocation (RMI)ãA new event modelãJava Database Connectivity (JDBC)Java did not have enough functions to sup-port system development until functions such asJavaBeans and JDBC were provided in thisversion.3)Version 1.2From JDK 1.2, Java was given the new brandname “Java 2.” In JDK 1.2, the following func-tions were added:ãJava Foundation Classes (JFC)ãInput Method Framework (IMF)ãCommon Object Request Broker Architecture(CORBA) supportãEJBãJava Plug-insAfter the release of Java 2, EJB made itsappearance and more enterprise systems weredeveloped using the server-side version of Java.It would appear that, at first, Java was expectedto be effective for solving the shortage of client-side applications on platforms other than Windows(as implied by the catch phrase, “write once, runanywhere”). However, server-side Java becamepopular in those days because of the expansion ofthe Internet.4)Version 1.3From JDK 1.3, Java and its related functionswere reorganized into the following three editionsbased on the target system environment: Java 2Platform, Enterprise Edition (J2EE); 1)  Java 2 Plat-form, Standard Edition (J2SE); 2)  and Java 2Platform, Micro Edition (J2ME).J2SE 1.3 had the following additional func-tions:ãHotSpot Client Virtual Machine (VM)ãJava Naming and Directory Interface (JNDI)ãRMI/Internet Inter-ORB Protocol (IIOP)ãSecurity enhancementsAfter the release of version 1.3, the way inwhich Java will be applied to enterprise systemsbecame clear with the editions based on target Major Java upgrades Version NameRelease dateMay 1995Java (announced) January 19961.0 JDK 1.0 February 19971.1 JDK 1.1 December 19981.2 Java 2 (JDK 1.2) July 20001.3 Java 2 (J2SE 1.3, J2EE 1.2, J2ME)February 20021.4 Java 2 (J2SE 1.4, J2EE 1.3, J2ME) Table 1Major version upgrades of Java.  87 FUJITSU Sci. Tech. J., 40 ,1, (  June 2004 ) S. Tasaka et al.: Latest Progress and Trends in Java/EJB Technologies  platforms. In particular, Java application to en-terprise systems became more popular after EJB2.0 and JavaServer Pages (JSP) were announcedin J2EE. Figure 1  shows the application modeland components supported by J2EE. To make iteasier to build enterprise systems through com-ponent-based development, several detailedapplication models based on EJB have been ad-vocated by companies and consortiums such asthe Component Consortium for EJB, 3)  which hasbeen established in Japan. Figure 2  shows theEJB-based application model of the ComponentConsortium for EJB. At the same time, becauseof J2ME, the application area of Java expandedto include mobile appliances, which led to the cur-rent widespread use of Java in mobile-phoneapplications.Among the enhancements in version 1.3, thefollowing functions added to EJB in EJB 2.0 areimportant because they can be used to design andimplement coarse-grained entities and make data-base access more efficient, which are both necessarytasks when developing enterprise systems:ãA new architecture for container-managedpersistence (CMP 2.0)ãSupport for the management of relationshipsamong entity beansãQuery syntax for select methods for entitybeans (EJB-QL)ãMessage-driven beans5)Version 1.4Until version 1.3, Sun Microsystems decid-ed the specifications of Java and its relatedfunctions. Since version 1.4, however, the specifi-cations have been decided in a more open manner.Now, new specifications and improvements of ex-isting specifications are made based on JavaSpecification Requests (JSRs) submitted by theJava community to a process called the Java Com-munity Process (JCP). 4)  When a JSR is submitted to the JCP, themember companies of the JCP discuss whether itshould be implemented. If they decide it shouldbe implemented, an expert group is establishedto decide the final specifications for the JSR. Onlymember companies of the JCP can submit a JSR,but submitted JSRs are made public on the JCP’sWeb site so the JCP can receive a wider range ofopinion.J2SE 1.4 was the first version whose specifi-cations were discussed and determined by the JCP.The following functions were added:ãXML supportãJava Web StartãA new I/O DBDBClientpresentationtierAppletHTMLWeb browserServerpresentationtierServletJSPServletcontainerBusinesslogictierEJBEJBcontainerEIStierDBMS Business logic tierEJB containerBusinessservicecomponentBusinessmodelcomponent Figure 1J2EE application model and components.Figure 2EJB-based application model of Component Consortiumfor EJB.  88 FUJITSU Sci. Tech. J., 40 ,1, (  June 2004 ) S. Tasaka et al.: Latest Progress and Trends in Java/EJB Technologies  ãA logging APIãAssertionãJava Secure Socket Extension (JSSE)In this way, the specifications of Java are now discussed and evolved within an open community. 3.Future enhancements of Java A roadmap for future enhancements of Javahas been released. 5)  The roadmap is shown in Table 2 .As described in Section 2, the applicationarea of Java has become wider and Java technol-ogy is becoming more popular. J2ME has beenadopted in mobile appliances such as mobilephones. J2EE has already reached the level of defacto standard in the development of enterprisemission-critical systems along with the rich en-hancement of EJB functions.However, Java is still difficult for beginnersto learn and there are relatively few high-leveldevelopers. For this reason, Java is not so suc-cessful in the area of section-wise application,where Basic and C# are used. On the other hand,Java is successful in the area of mobile applianc-es and enterprise systems.As a result, for the next version of Java, easeof development rather than function enhancementwill be the priority issue. This could be the larg-est change of policy since Java was born.The next version of Java will be J2SE 1.5(code name “Tiger”). For J2SE 1.5, the followingfive themes will be considered:1)Quality: compatibility will be extremely im-portant.2)Performance and scalability3)Ease of development4)Monitoring and manageability5)Desktop clients“JSR-176: J2SE 1.5 (Tiger) Release Contents”is being developed in the JCP according to thesethemes. Furthermore, several JSRs have beensubmitted with respect to the specifications ofmore detailed functions ( Table 3 ).The final version of J2EE 1.4 was releasedin November 2003. EJB 2.1, in particular among Table 2J2SE Technology Update and Roadmap. DateVersion (Code name)Summer 20041.5 (Tiger)Early 20051.5.1 (Dragonfly)After 20051.6 (Mustang) Table 3JSR-176: J2SE 1.5 (Tiger) Release Contents. JSR-003Java Management Extensions (JMX) Specification JSR-013Decimal Arithmetic Enhancement JSR-014Add Generic Types to the Java Programming LanguageJSR-028Java SASL Specification JSR-114JDBC Rowset Implementations JSR-133Java Memory Model and Thread Specification RevisionJSR-163Java Platform Profiling Architecture JSR-166Concurrency UtilitiesJSR-174Monitoring and Management Specification for the Java Virtual MachineJSR-175A Metadata Facility for the Java Programming LanguageJSR-199Java Compiler API JSR-200Network Transfer Format for Java Archives JSR-201Extending the Java Programming Language with Enumerations, Autoboxing, Enhanced for Loops and Static ImportJSR-202Java Class File Specification UpdateJSR-204Unicode Supplementary Character SupportJSR-206Java API for XML Processing (JAXP) 1.3
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