http://www.songhaysystem.com/kb/subject/java The Funky Knowledge Base at songhaysystem.com. The subject of this channel is Java Technologies. Tue, 02 Dec 2008 21:03:00 GMT http://www.songhaysystem.com/kb/number/2076072075/subject/java Article Excerpt: Eclipse Bugs 8521 and 19771 have over one hundred combined votes, resulting in one of the ten most voted for features of Eclipse. However, implementing Column Mode (aka. rectangular selection) is not easy and involves numerous API additions, namely to the… Tue, 02 Dec 2008 21:03:00 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076072070/subject/java Article Excerpt: System.exit should be used with care. The normal method of terminating a program is to terminate all user threads. Cases in which System.exit is appropriate : * utility scripts * GUI applications, in which the event dispatch user thread is creat… Tue, 02 Dec 2008 20:34:39 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076072082/subject/java Article Excerpt: You shouldn't use accessor methods (getters and setters) unless absolutely necessary because these methods expose information about how a class is implemented and as a consequence make your code harder to maintain. [http://www.javaworld.com/javaworld/jw-… Tue, 02 Dec 2008 21:42:32 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076072077/subject/java Article Excerpt: There is no such thing as a byte or short literal. You would have to write it with a cast e.g. (byte)0xff or (short)-99. … Escape sequences inside char and String literals include: ' ' space '\u003f' Unicode hex, (must be exactly 4 digits to give a 1… Tue, 02 Dec 2008 21:18:52 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076072079/subject/java Article Excerpt: Java is always pass-by-value. The difficult thing can be to understand that Java passes objects as references passed by value. It goes like this: public void foo(Dog d) { d.name == "Max"; // true d = new Dog("Fifi"); d.name == "Fifi"; // true } D… Tue, 02 Dec 2008 21:34:20 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076072083/subject/java Article Excerpt: C# allows restricted use of pointers. …Java does not allow pointers or pointer-arithmetic to be used. … C# allows the programmer to create user-defined value types, using the struct keyword. … Enumerations in C# are derived from a primitive 8, 1… Tue, 02 Dec 2008 21:59:02 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076072078/subject/java Article Excerpt: An overview of the Java application launcher is here: http://java.sun.com/j2se/1.4.2/docs/tooldocs/windows/java.html The most important thing someone from the Microsoft Windows world needs to understand about the Java application launcher is that we… Tue, 02 Dec 2008 21:30:26 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076072058/subject/java Article Excerpt: Petr Pisl’s article about the --userdir has a paragraph you should read first: “I don't use installers, I always download NetBeans as a zip file. These are available on nightly build download page, where OS Independent Zip item in has to be selected i… Sat, 18 Oct 2008 01:47:16 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071997/subject/java Article Excerpt: The first kind of exception is the checked exception. These are exceptional conditions that a well-written application should anticipate and recover from. …Checked exceptions are subject to the Catch or Specify Requirement. All exceptions are checked ex… Sun, 24 Aug 2008 07:24:15 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071996/subject/java Article Excerpt: Valid Java programming language code must honor the Catch or Specify Requirement. This means that code that might throw certain exceptions must be enclosed by either of the following: * A try statement that catches the exception. The try must provide a h… Sun, 24 Aug 2008 07:15:56 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071998/subject/java Article Excerpt: Java’s generics implementation was based on a project originally called Pizza, which was done by Martin Odersky and others. Pizza was renamed GJ, then it turned into a JSR and ended up being adopted into the Java language. And this particular generics p… Mon, 25 Aug 2008 00:08:16 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071972/subject/java Article Excerpt: From the NetBeans wiki: “You can run NetBeans with the --fontsize <size> option. The default <size> value is 11. You can set it to 12 or even a higher value and see if it works better for you. The --fontsize argument applies to fonts used in menus, dial… Wed, 02 Jul 2008 03:01:59 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071973/subject/java Article Excerpt: -h, --help: Print descriptions of common startup parameters. --jdkhome jdk_home_dir: Use the specified version of the JDK instead of the default JDK. --cp:p classpath: Prepend the specified classpath to the IDE's classpath. This option is generally not … Wed, 02 Jul 2008 03:06:44 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071932/subject/java Article Excerpt: 1) Download log4j http://logging.apache.org/site/binindex.cgi 2) Unpack the .zip file in your Java folder (In Windows it is usually C:\Program Files\Java\) 3) In Eclipse: Window > Preferences… > Java > Build Path > User Libraries > New: "log4j" > OK A… Fri, 28 Dec 2007 18:52:08 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071913/subject/java Article Excerpt: You can clean your recent workspaces list in eclipse for the Select a Workspace dialog by editing a text file called org.eclipse.ui.ide.prefs in your eclipse installation folder at this relative path (in Linux): configuration/.settings Edit the RECE… Fri, 09 Nov 2007 20:52:29 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071907/subject/java Article Excerpt: JAXP and the associated XML APIs: JAXP: Java API for XML Processing JAXB: Java Architecture for XML Binding JDOM: Java DOM DOM4J JAXM: Java API for XML Messaging JAX-RPC: Java API for XML-based Remote Process Communications JA… Fri, 19 Oct 2007 05:02:00 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071906/subject/java Article Excerpt: * “The current APIs for accessing XML documents either serially or in random access mode are, respectively, SAX and DOM…” * “The XSL standard has two parts, XSLT (the transformation standard, described next) and XSL-FO (the part that covers forma… Fri, 19 Oct 2007 04:53:45 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071905/subject/java Article Excerpt: * “To complete this journeyman’s introduction to XML, note that an XML file always starts with a prolog… it may contain the following attributes: version… encoding… standalone… The prolog can also contain definitions of entities…” * “An… Fri, 19 Oct 2007 04:24:17 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071903/subject/java Article Excerpt: Singleton: public class Singleton { private static Singleton theInstance = null; private Singleton() {} public static Singleton Instance() { if (theInstance == null) theInstance = new Singleton(); … Fri, 19 Oct 2007 04:03:25 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071814/subject/java Article Excerpt: 2.3 Basic configuration "Hibernate can be configured to run in almost any Java application and development environment... It’s important to understand the difference in configuring Hibernate for managed and non-managed environments..." Tomcat is consi… Wed, 11 Apr 2007 01:38:47 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071813/subject/java Article Excerpt: 2.2 Understanding the architecture "The programming interfaces are the first thing you have to learn about Hibernate in order to use it in the persistence layer of your application." There are about four types of interfaces: i) The Session, Transaction,… Wed, 11 Apr 2007 01:30:47 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071812/subject/java Article Excerpt: 2.1 “Hello World” with Hibernate "Hibernate applications define persistent classes that are 'mapped' to database tables... Our persistent class can be used in any execution context at all---no special container is needed." Hibernate depends on its Se… Tue, 10 Apr 2007 01:38:56 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071811/subject/java Article Excerpt: 1.4 Object/relational mapping "Now that we’ve looked at the alternative techniques for object persistence, it’s time to introduce the solution we feel is the best, and the one we use with Hibernate: ORM." "Isn’t ORM a Visio plugin? The acronym ORM… Tue, 10 Apr 2007 00:53:52 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071810/subject/java Article Excerpt: 1.3 Persistence layers and alternatives "A layered architecture defines interfaces between code that implements the various concerns, allowing a change to the way one concern is implemented without significant disruption to code in the other layers." "L… Tue, 10 Apr 2007 00:37:08 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071809/subject/java Article Excerpt: 1.2 The paradigm mismatch "The problem of granularity" identifies the mismatch between Java type definitions and the obstacles of SQL user-defined types (UDT). "Unfortunately, UDT support is a somewhat obscure feature of most SQL database management sys… Mon, 09 Apr 2007 02:41:18 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071808/subject/java Article Excerpt: 1.1 What is persistence? "To use Hibernate effectively, a solid understanding of the relational model and SQL is a prerequisite." Here is a list of SQL terms: * Data Definition Language (DDL): CREATE, ALTER * Data Manipulation Language (DML): INSERT, UP… Mon, 09 Apr 2007 02:12:54 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071806/subject/java Article Excerpt: 2.2 The Request Processing Lifecycle The Request Processing Lifecycle has 10 parts in six "primary phases": Restore View, Apply Request Values, Process Events, Process Validations, Process Events, Update Model Values, Process Events, Invoke Application, … Thu, 22 Mar 2007 23:16:02 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071805/subject/java Article Excerpt: 2.1.7 Messages Messages are communications with the user. Other UI components can be associated with the HtmlMessages components in a declarative way like this: <h:message id="errors" for="helloInput" style="color:red;display… Tue, 20 Mar 2007 22:54:00 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071804/subject/java Article Excerpt: 2.1.6 Events and listeners "JSF leverages JavaBeans to handle events with event objects and listeners, just like Swing. Any component may fire zero or more events, and developers (or components themselves) can register zero or more listeners to handle th… Thu, 15 Mar 2007 00:35:24 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071802/subject/java Article Excerpt: 2.1.5 Converters Converters do the job converting object and scalar values into strings. They also handle the task of localization. The sample below declares a DateTime converter for an HtmlOutputText component: <h:outputText value="#{user.dateOfBir… Tue, 13 Mar 2007 21:45:21 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071801/subject/java Article Excerpt: 2.1.4 Backing beans In the MVC world backing beans play the part of the controller, the interaction between the UI and the model. "Backing beans generally contain properties you want to retrieve from users and event listener methods... that process those… Tue, 13 Mar 2007 21:24:29 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071800/subject/java Article Excerpt: 2.1.2 Renderers "When components render themselves, it's called the direct implementation model, but JSF also supports the delegated implementation model..." The classes that implement these implementation models are called "renderers." All of the standa… Tue, 13 Mar 2007 20:00:21 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071803/subject/java Article Excerpt: Read me file: ./docs/about.html Glassfish server: ./bin/asadmin start-domain domain1 Glassfish server administration: admin console: http://localhost:4848 Wed, 14 Mar 2007 01:27:39 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071799/subject/java Article Excerpt: 2.1.1 User interface components "Packaging UI elements as a component... makes development easier because the core functions are encapsulated within a reusable piece of code." "The way a component looks is how it is rendered." A properly designed JSF co… Mon, 12 Mar 2007 23:36:01 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071798/subject/java Article Excerpt: 2.1 The key pieces of the pie "Eight core terms come into play when you're developing JSF applications...": (i) UI component (control or component); (ii) Renderer; (iii) Validator; (iv) Backing beans; (v) Converter; (vi) Events and listeners; (vii) Messa… Mon, 12 Mar 2007 23:18:38 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071797/subject/java Article Excerpt: 1.5.4 Configuration with faces-config.xml "Technically, JSF supports multiple configuration files, but we'll keep things simple for now." "...a JSF configuration file is an XML document whose root node is <faces-config>..." To reference beans via JSF E… Mon, 12 Mar 2007 22:15:33 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071796/subject/java Article Excerpt: 1.5.2 Dissecting goodbye.jsp "One of the HtmlOutputText components references the same helloBean object as the previous page. This works fine because the object lives in the application's session and consequently lives between page requests." 1.5.3 Exa… Thu, 08 Mar 2007 23:30:12 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071794/subject/java Article Excerpt: 1.5.1 Dissecting hello.jsp The tag library indicated by http://java.sun.com/jsf/core provides for validation, event handling and the like. The tag library indicated by http://java.sun.com/jsf/html provides for the JSF UI components like text boxes, outp… Thu, 08 Mar 2007 23:02:57 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071793/subject/java Article Excerpt: 1.4 Components Everywhere "A software component is a unit of composition with contractually specified interfaces and explicit context dependencies only. A software component can be deployed independently and is subject to composition by third parties [Sz… Tue, 06 Mar 2007 00:47:51 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071791/subject/java Article Excerpt: According to ranch hand, Scott Dunbar at saloon.javaranch.com, the Tomcat 5.x message during start up, "INFO: The Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: ...," means … Wed, 28 Feb 2007 19:26:53 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071790/subject/java Article Excerpt: 1.3.1 Why do we need frameworks? "Forms are just one example of tasks that servlets and JSP don't completely solve. Web applications have to manage a lot of pages and images, and referencing all of those elements within larger applications can become a n… Wed, 28 Feb 2007 00:22:07 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071789/subject/java Article Excerpt: 1.2.4 JavaBeans "JavaBeans is a full-fledged component architecture designed with tool support in mind... JavaBeans is the technology that enables Swing... JavaBeans also includes a powerful event model (the same one used with Swing and JSF components), … Tue, 27 Feb 2007 23:37:22 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071788/subject/java Article Excerpt: 1.2.2 Servlets HTTP requests to a Java Application server are handled by Servlets. Servlets provide "an object-oriented view of the world that makes it easier to develop web applications." "A standard J2EE web application is, by definition, based on the… Tue, 27 Feb 2007 22:59:14 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071787/subject/java Article Excerpt: RAD tools have four layers: (i) an underlying component architecture, (ii) a set of standard widgets, (iii) and application infrastructure, (iv) the tool itself. JavaServer Faces (JSF or Faces) defines three of the four layers of RAD tools, leaving "the … Tue, 27 Feb 2007 21:35:08 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071775/subject/java Article Excerpt: Filtering TODO tasks per package means filtering "On selected resource and its children." In the Tasks View (Window > Show View > Tasks), click the Filters... button to show the Filters dialog. Select the "On selected resource and its children" option to … Fri, 13 Oct 2006 11:23:13 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071776/subject/java Article Excerpt: <?xml version="1.0" encoding="utf-8" standalone="yes"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <%@page pageEncoding="UTF-8" contentType="text/html; charset=UTF-8" %> <html … Fri, 13 Oct 2006 14:41:26 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071770/subject/java Article Excerpt: The opinion here is that it is misleading and a waste of time to ask an experienced C# programmer, "Do you know Java?" What is useful and educational is the question, 'Do you know the Java Bean?' The first question is a matter of syntax and is trivial co… Wed, 04 Oct 2006 19:47:29 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071768/subject/java Article Excerpt: The tk.eclipse.plugin.htmleditor may load slowly due to the enabled HTML validation option under Project > Properties > Amateras > Validation: Uncheck the HTML Validation box and this should improve performance. This guidance applies to version 2.0.… Tue, 03 Oct 2006 23:31:12 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071312/subject/java Article Excerpt: You are limited to testing the data type char or all the integer types but long. Each case can only hold one value; however when a case does not contain a break statement code execution continues to the next case. Tue, 19 Dec 2000 22:03:37 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071310/subject/java Article Excerpt: //The number we want to show. double dbl = 10000.0 / 3.0; //Get a Locale object from the java.util package. java.util.Locale locale = java.util.Locale.getDefault(); //Format the number for a given Locale. java.text.NumberFormat nf = java.text.NumberForm… Sat, 16 Sep 2000 14:28:00 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071311/subject/java Article Excerpt: java.lang.String str = "1234567"; boolean bln = false; bln = ("123".equals(str.substring(0,3))); java.lang.System.out.println(bln); Sat, 16 Sep 2000 14:28:00 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071313/subject/java Article Excerpt: I feel obliged to apologize before I do this: sorry. Associating VB with Java is pretty nasty. Okay: VB is all about encapsulating procedures; Java is all about encapsulating data. VB (as of 6.0) has modules; Java has classes. Java's equivalent of a sta… Sat, 16 Sep 2000 14:28:00 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/2076071291/subject/java Article Excerpt: Objects Data is encapsulated in an object. The data is stored inside the object as "instance variables" or "instance fields." If the access modifier "private" is used when creating instance fields, then the principle of "encapsulation" is enforced. The p… Sat, 16 Sep 2000 14:28:00 GMT Bryan Wilhite http://www.songhaysystem.com/kb/number/906518287/subject/java Article Excerpt: Perhaps it is not too dangerous to think of the AWT in VB terms. Let's try. The VB form should translate to the Container and the form's grid could somehow make it to Java's Layout Manager. VB Form Controls are answered in Java by Components. The Componen… Wed, 23 Sep 1998 02:59:41 GMT Bryan Wilhite