java

The Java program design language(call Java language as follows) that the Java is released May in 1995 by the company of Sun Microsystems with the generic name of Java terrace.The HotJava browser(support Java applet) which uses a Java realization showed Java magic power:The Web, Internet of cross-platform, movement compute.From now on, the Java is extensively accept and pushed Web of quick develop, the in common use browser all supports Java applet now.On the other hand, the Java technique also continuously renews. The Java terrace is connected composing by the Java Virtual Machine(Java Virtual Machine) and the Java applied plait distance.The Java application plait distance connected to provide an independence at the operate system for the Java application of standard connect, can is divided into basic part with expand part.After the hardware or operate system terrace ascend install a Java terrace, the Java application procedure can circulate.The Java terrace has already imbed almost all operate systems now.Thus the Java procedure can be edit and translate with once, can circulate in various system.The Java application plait distance connects the version has already developped to 1.2 versions from the 1.1. x.Currently the in common use Java terrace is according to the Java1.4 and the edition is a Java1.6 recently. The Java is divided into three individuals to fasten JavaSE, JavaEE, JavaME.
Java languageThe Java language is a support network to compute of face to object program design language.The Java language absorbed Smalltalk language and C++the advantage of language, and increased other characteristics, erupt program design, network correspondence such as support, and the multi-media data control etc..Main characteristic is as follows: 1) the Java language be simple.Phrasing and C language and C of Java language++the language be very close and make most procedure members very easily study with use Java.On the other hand, the Java threw C away++ medium few usage of, very difficult comprehension of, puzzling those characteristics, such as operation the sign be heavy to carry, much inherit, auto of compulsive type conversion.In particular, the Java language doesn't use to point needle, and provided the waste of the auto collections, need not make the procedure member manage but worry for the memory. 2) the Java language be 1 to face to object.The Java language provides a type and connect and inherit etc. original language, for the sake of simple rise to see, of support of list inherit, but support connect the much inherit of of , and support with connect the carry out of of a mechanism.(key word is implements)The Java language supports dynamic state's bind to settle completely, but C++ language rightness falsely function usage the dynamic state bind settle.In fine, the Java language is purely 1 to face to object program design language. 3) the Java language be a distribute type.The Java language supports the applied development of the Internet, there is a network application plait distance in the basic Java application plait distance connect connecting and it provided to used for the type of the network application plait distance database and include URL, URLConnection, Socket, ServerSocket etc..The Java RMI(the long range method activate) mechanism is also the important means of application of the development distribute type. 4) the Java language be strong.Automatic collections etc. of Java strong type mechanism, excrescent processing, waste is important assurance of the Java procedure haleness.It is a Java wise choice towards pointing throw needle away of.The Java safe check mechanism makes the Java have haleness more. 5) the Java language be safe.The Java is usually used in the network environment, is this, the Java provided a safe mechanism in order to prevent the attack of malice code.In addition to the Java language have of many safe characteristics, the Java has to the type which passes a network download a safety guard against a mechanism(type ClassLoader), such as assign different name space in order to prevent act for natively and together, word stanza code check, and provide a safety management's mechanism(type SecurityManager) to make the Java applied to establish safe sentinel. 6) the Java language is a system structure neutral of.The Java procedure(the suffix is for the java document) circulate in any system is edit and translate for the byte code format(the suffix is a class document) of system structure neutral on the Java terrace, then can be carry out this Java terrace.Network environment and distribute of software of this kind of path suitable for different Gou. 7) the Java language can transplant.This kind of can transplant sex to come from the system structure neutral, on top of that, the Java strictly ruled each length of basic data type.Java system's also hasing very strongly can transplant sex, the Java edits and translate a machine to use a Java realization, and the Java movement environment uses ANSI C a realization. 8) the Java language be an explanation type.Such as front say, the Java procedure circulate in any system is edit and translate for the byte code format on the Java terrace, then can be carry out this Java terrace.While circulate, Java within Java terrace explanation the machine carry on a hermeneutic performance to these byte codes and carry out to need in the process of the type is in alliedly connect the stage the quilt load in the movement the environment. 9) the Java be a high performance.With those of the deluxe script language compare and the Java is really a high performance.In fact, the Java movement speed edits and translate a machine a technical development along with the JIT(Just-In-Time) more and more close at the C++. 10) the Java language be a multi-threading.In the Java language, the line distance is a kind of special object and it has to be establish by Thread or its son() type.Usually have two kinds of methods to establish a line distance:It a, the usage type Gou carried out 1 Runnable to connect oscular object to pack into a line distance for the Thread(Runnable) structure son, it two, living a son to lay equal stress on to write a run method from the Thread parties, usage that son establish of the object is a line distance.Remarkable is Thread has already carried out Runnable to connect, therefore, the whichever line distance all has it of run method, but included the code of movement that line distance want in the run method.The activity of line distance is control by a set of method. The Java language supports in the meantime carry out of several line distanceses, and provide the synchronous mechanism of of multi-threading.(the key word is a synchronized) 11) the Java language be dynamic.One of the design targets of Java language is an orientation at the environment of dynamic state variety.The type that the Java procedure need ability dynamic state the ground be load in to circulate environment, can also pass a network to load in the type need.This also is advantageous to get stripe of software.Moreover, the type in the Java has 1 circulate time of mean, can carry on circulate time of type check. The good characteristic of Java language makes the Java application have matchless haleness and credibility and this also reduced the maintenance expenses of applied system.The Java can shorten development time of apply the system to the API of Qian inside the object technical overall support and the Java terrace and decline low cost.The Java edits and translate once, the characteristic that can circulate everywhere can make it provide one everywhere available open structure with deliver the low cost way of information between many terraces.Especially Java business enterprise application the plait distance connect to compute for the business enterprise and the electronic commerce applied system to provide concerning the technique with abundant of type database. 1) the JDBC(the Connectivity of the Java Database) provide to link unify of various relation database to connect. 2) the EJB(Enterprise JavaBeans) make the developer expediently establish, deployment and management cross-platform of apply according to the business enterprise of the module. 3) the Java RMI(the Method Invocation of the Java Remote) use to develop the distribute type Java application procedure.The method ability of a Java object drive long range Java the Virtual Machine adjust to use.So, the long range method activates and can take place in the on an equal footing both ends, can also take place to carry at the customer with of server, as long as both parties' applied procedures all use what Java write. 4) the Java IDL(the Definition Language of the Java Interface) provide to meet with have no of CORBA(the Architecture of the Request Broker of the Common Object) with each other operability.This make the Java can integrate different Gou of business information resources. 5) the JNDI(the Interface of the and Directory of the Java Naming) provide arrive from the Java terrace of unify of meet of conjunction.This connected to shield what business enterprise network use various assign name to serve with catalogue. 6) the JMAPI(Java Management API) provides the object and method that a the whole set enrich for the development that the different Gou network top system, network kimono works a management. 7) the JMS(Java Message Service) provide the business enterprise news the service, like dependable news brigade row, release with the subscription correspond by letter, and relevant push to pull(Push/Pull) each technical aspect. 8) the JTS(Java transaction Service) provide an open of the processing resources of the access business standard, these the business handle the resources include management and supervision of the application procedure of the business processing, business processing. In the Java technique, it is still worthy of pay attention to to have JavaBeans, it is a liberal of the module system of the standard structure, it independence at the terrace, but use Java language.A JavaBean is a Java which satisfies JavaBeans norm and usually defined a thing or concept of realistic world.The main characteristic of a JavaBean includes attribute, method and affairs.Usually can be able to see a ground of operation JavaBean in the development environment(like Studio and the for Java of the IBM VisualAge of the Sun Java) of norm of a support JavaBeans, can also use JavaBean to construct a new JavaBean.The JavaBean advantage still lies in Java to bring of can transplant sex.Now, the EJB(Enterprise JavaBeans) expands the JavaBean concept to the Java service to carry module system structure and this model supports a multi-layer distribute type object application.In addition to JavaBeans, the module system of the typical model structure still has DCOM and CORBA, concerning these module system structure of the thorough discussion outran the scope of this book.
The Java opens source item
Spring Framework 【the Java open the source J2 EE frame 】
Spring is 1 solved many in the J2 EE development familiar problem of strong frame. The Spring provided management business the consistent method of the object and encouraged infusion to pick up a people plait distance but is not to type the good habit which weave a distance.The Spring structure foundation is according to the Control container of the Inversion of of usage JavaBean attribute.However, this be one part in the only complete diagram view:The Spring is the one and only in the aspects of using IoC container as to finish set up to pay attention to all structure layer of complete solution. The Spring provided the only data interview abstract, include in brief with efficient JDBC frame, biggest improved an efficiency and reduced a possible mistake.The Spring data interview structure still integrated Hibernate and other solutions of Os/Rs mapping.The Spring still provided the only business management abstract, it can manage a technique in various first floor business, for example the JTA perhaps JDBC business provide a consistent plait distance model. The Spring provided an AOP frame which writes with the standard Java language, it provided to declare business management and other businesses enterprise business of type for POJOs-if you need-can also carry out your own aspects.This frame is enough strong and making application procedure can lay aside EJB complexity and enjoy with traditional EJB related key service in the meantime.The Spring still provides and can integrate with IoC container of strong but vivid frame of MVC Web.【SpringIDE:Next assistance of the Eclipse platform develops a plug-in 】.WebWork 【the Java open source Web a frame 】
WebWork from OpenSymphony organization development of, concentrate on module to turn and the code be heavy to use of the pull up type MVC mode J2 EE Web frame.WebWork currently the latest edition is 2.1, the WebWork2 in nowadays.The x precursor is a Rickard Oberg the WebWork of the development, but the WebWork has already been dismantle to be divided into two items: Xwork1 and WebWork2 now. Xwork the simple and direct and vivid function be strong, it is the Command mode of a standard realization, and completely escape from from the web layer. The Xwork provided a lot of core functions:The head intercepts machine(interceptor), form and list attribute while circulate verification, the type convert, strong expression type language(the OGNL – Language of the Graph Notation of the Object), IoC(Inversion of the Control set upside down a control) container etc.. WebWork2 establishment at Xwork on, processing respond to of HTTP with claim.The WebWork2 uses ServletDispatcher to request HTTP of become Action(business layer Action), the reflect of scope of the session(conversation) application(application procedure) shoot and the request claim parameter reflects to shoot.WebWork2 support sees chart more to show, see the diagram part can use JSP, Velocity, FreeMarker, JasperReports, XML etc..Added to AJAX support in the WebWork2.2, this support was the foundation which sets up these two frames at the DWR and the Dojo on.【EclipseWork:Used for a WebWork assistance an Eclipse plug-in of the development 】Struts 【the Java open source Web a frame 】
The Struts is 1 according to the MVC frame of Sun J2 EE terrace and mainly adopt Servlet and JSP technique to carry out.Because the Struts can well satisfy application development of need, in brief and easily use, nimble quick, in past year in is pay attention to rather.The Struts is the Servlet, JSP, from definition label and information resources(message resources) integrate to in a frame for unify and develop a personnel to make use of it to carry on development need not again oneself the coding carry out complete set MVC mode, biggest saved time, so say that the Struts is that one is very quite good of applied frame.【StrutsIDE:Used for a Struts assistance an Eclipse plug-in of the development 】Hibernate 【the Java open a source to hold out for long time a layer a frame 】
The Hibernate is an object relation which opens a source code to reflect to shoot a frame, it carried on the object of lightweight to pack very much to the JDBC and make Java procedure the member can follow one's inclinations of the usage object plait distance thinking to manipulate a database. The Hibernate can apply in any situation which use JDBC, since can carry procedure at the Java customer practical, can also use in the Web application of Servlet/JSP, what to have revolution meaning most BE, the Hibernate can replace CMP in the applied EJB J2 the EE the structure, completion data hold out for long time turn of heavy responsibility.The Hibernate assistance that is under the Eclipse platform develops tool: 【Hibernate Synchronizer 】【MiddlegenIDE 】Quartz 【the Java open source Job to adjust a degree 】
The Quartz is an OpenSymphony to open source organization to open source item in another the realm of Job scheduling and it can combine together with the J2 EEs and the J2 SE application procedure and can also use alone.The Quartz can be use to establish in brief or in order to circulate 10, 100 even are a quite a few is ten thousand day schedules with so complicated Jobs.The Jobs can make into standard Java module or EJBs.Quartz the latest edition is a Quartz 1.5.0.Velocity 【the Java open source template engine 】
The Velocity is 1 according to the java template engine(template engine).It allows anyone only simple usage template language(template language) to quote from from the object of java code definition.When the Velocity applies at the web development, interface design personnel can development with java procedure the personnel synchronously develops a web station which follows MVC structure to order, be also say, page design personnel can with the manifestation effect which pay attention to a page, but from java procedure development the personnel pay attention to business logic coding.Velocity java code the separation comes out from the web page, provided convenience for the long-term maintenance that the web stands to order so, also is us in the JSP and the PHP outside provided a kind of project that can choose again in the meantime. The Velocity ability far not only web station orders to develop this realm, for example, it can from SQL and PostScript, XML of the template(template) creation, it can be also regarded as an independence tool to produce a source code and report, perhaps Be the integrated module of other systems usage.The Velocity can also develop structure to provide a template service(template service) for the Turbine web.Velocity+the Turbine provide the way of a template service to allow a web application to carry on a development by a real MVC model. 【VeloEclipse:The Velocity is under the Eclipse platform of an assistance develop a plug-in 】IBATIS 【the Java open a source to hold out for long time a layer a frame 】
Use the ORM mechanism that the ibatis provide, carry out personnel but speech to the business logic, what to face is a pure Java object, this with carry out ORM but talk through a Hibernate basic consistent, but for concrete data operation, Hibernate would automatically born SQL language sentence, but the ibatis then request developer to write a concrete SQL language sentence.The opposite Hibernate waits "full-automatic" ORM mechanism but speech and the ibatis transplants the concession of sex by workload and database of SQL development and provided larger free space for the system design.A kind of beneficial complement that the conduct and actions"full-automatic" ORM carry out, the ibatis emergence show don't have meaning.The Compiere ERP& CRM 【the Java open source ERP and CRM system 】
The Compiere ERP& CRM for global scope inside of in the small scaled business enterprise provide a comprehensive type a solution and overlay a management, supply chain to arrive finance a management from the customer of all realms, support much organizes, many the currency grow, many accountancy's mode, many costing, many the language grow, many tax system etc. internationalization characteristic.Be easy to gearing, be easy to an implement and be easy to an usage.Needs short and a few hours, you can use to state buy-purchase-invoice-payment, quote-order-invoice-accept payment, product and list price, property management, customer relation, supplier relation, employee relation and conduct accomplishment analysis etc. strong function.Roller Weblogger 【the Java open the source Blog Bo guest 】
This weblogging designs more and delicately and the source code is a good study data.It support weblogging should have of characteristic such as:Comment on function, the hat you see is what you get HTML edit, TrackBack, provide page template, RSS syndication, blogroll management with provide a XML-RPC to connect.
Eclipse 【the Java open a source development tool 】The Eclipse platform is the development frame that the IBM donates toward the development source code community, the reason that it isn't famous because the IBM enounce devotion development of funds total amount-4 ten million USD, but is as it does huge devotion bring of result:One is mature and with meticulous care design of and expansive system structure.
XPlanner 【the Java open source item a management 】XPlanner 1 according to Web XP team plan with follow tool.The XP special development concept is like iteration, the user stories etc., the XPlanners all provided opposite in response to of of management tool, XPlanner support XP development process, and resolve to make use of XP thought to develop the problem that the item run into. The XPlanner characteristics include:Simple model programming, the virtual notes card(Virtual note cards), iterations, user stories and work record of track, not yet finished stories automatic Die generation, work time track, born team efficiency, personal man-hour statement, SOAP interface support.
HSQLDB 【the Java open source DBMS a database 】
HSQLDB(Hypersonic SQL) is the relation type that the pure Java develop database, and provide JDBC to drive an access data.Support the ANSI-92 standard SQL phrasing.And he share of the space be very small.About only 160 Ks, own fast database engine.
Liferay 【the Java open source Portal gate 】
Represented the J2 of the integrity EE an application, used Web, EJB and JMS etc. technique, especially its stage interface part usage Struts frame technique, according to XML portlet allocation document can at liberty the dynamic state expand, used Web Services to support obtain of some long range informationses and use Apahce Lucene to carry out a full text index function.Main characteristics: 1, provide single debarkation to connect, have another attestation mode(LDAP or SQL); 2, the managing person can pass customer's interface to easily manage a customer, set, role; 3, customer's ability be able to according to need to make to order characteristic portal layout; 4, can at essential J2 EE application server up circulate, like JBoss+Jetty/Tomcat, JOnAS; 5, support essential database, such as the PostgreSQL, MySQL; 6, used the third to put of open source item, such as the Hibernate, Lucene, Struts; 7, support various languages including Chinese; 8, adopt most the forerunner's technique Java, EJB, JMS, SOAP, XML;
JetSpeed 【the Java open source Portal gate 】The Jetspeed is the realization of a business enterprise information which opens a source code gate(EIP) and the technique of usage is Java and XML. The customer can use a browser, cellular phone perhaps other Jetspeed of the equipments interview which supports WAP agreement install of the information gate obtain an information. The Jetspeed plays information concentration the role of the machine and it can get up information concentration and very easily provide to the customer.The Jetspeed is have as follows of characteristic:
* The Java Portlet will soon become standardize API* Include JSP and Velocity according to the layout of template* Exchange through a liberal contents synchronous technique support long range XML contents* The main page made to order to recognize tacitly* The usage database carries on customer's attestation* The memory slowly saves a technique and speed a respond to of page* Pass the Summary technique of the Rich Site, support a synchronous contents* With Cocoon, WebMacro, the Velocity is integrated.* The Language(WML) of the Wireless Markup support* The allocation document which uses a XML format registers portlet.* The Web Application Archive(WAR) of integrity support* The Web applies the infrastructure of procedure development* Can at native slowly save a long range contents* Synchronous with Avantgo* Can transplant the JDK1.2 and Servlet of all support 2.2 terraces* With Turbine mold piece kimono duty integrated* Can install medium type and the different enactment of language according to the customer, produce different characteristic service* Continuously turn a service to make from of the portlet can easily save each customer's appearance, page and portlet* The technique of use the skin makes the customer be able to choose portlet color and manifestation attribute* From definition function yes the managing person can choose portlet and define personal page of layout* In the database saving PSML* Pass Jetspeed safe customer, set, role and legal power of the portlets management* According to role to visit portlet to carry on a controlJOnAS 【the Java open the source J2 EE server 】
The JOnAS is a J2 EE realization which opens a source code, development in the ObjectWeb association.The Web container integrating Tomcat or Jetty to become it matches by insure Servlet 2.3 is 1.2 norms with JSP.JOnAS server dependence or carry out following Java API:JCA, JDBC, JTA, JMS, JMX, JNDI, JAAS, JavaMail.JFox 3.0 【 Javas open the source J2 EE server 】
The JFox is the Application Server of the Open Source Java EE, concentrate on the application server of the Java EE which provides lightweight, from 3.0 beginnings, the JFox provided the MVC frame for turn of a support mold piece to simplify EJB and the Web applied development! If you are look for a simple, light quantity, efficiently, perfect Java EE development terrace, so the JFox is exactly you demand.
JFox 3.0 own following characteristic:
1. The IoC re- designed is tiny inside the pit and integrate an OSGi mold piece to turn thought 2. Design into built-in structure, can with any Java Web the Server integrate deployment 3. Support EJB3, JPA norm, support to circulate EJB and JPA module with the outside of the container's two kinds of method inside container 4. Support the EJB releases into Web Service 5. Adopt the JOTM(http://jotm.objectweb.org/) provides a business processing and support two stages hand over(2 PCs) 6. Adopt the XAPool(http://forge.objectweb.org/projects/xapool/) provides XA DataSource and support the intelligence conjunction pond management 7. Inside place a MVC frame, carry out automatic Form Mapping, Validator, Uploading etc. function, support page engine of the JSP/Velocity/Freemarker, and support directly to infuse into EJB in the Action 8. Support a much applied mold piece deployment, let medium large the application well enjoys a mold piece to turn the advantage that the development bring 9. Provide the Manager management the mold piece, while can look into and manage various movement parameter 10. Provide the Petstore application mold piece which rewrites according to the JFox special features