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| <meta name="author" value="Jon S. Stevens"> |
| <meta name="email" value="jon@latchkey.com"> |
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| <title>Velocity - You make the decision - Implementation</title> |
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| <a href="http://jakarta.apache.org"><img src="http://jakarta.apache.org/images/jakarta-logo.gif" border="0"/></a> |
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| <a href="http://jakarta.apache.org/velocity/"><img src="../images/logo.gif" alt="Velocity" border="0"/></a> |
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| <p><strong>About</strong></p> |
| <ul> |
| <li> <a href="../index.html">Overview</a> |
| </li> |
| <li> <a href="../getting-started.html">Getting Started</a> |
| </li> |
| <li> <a href="http://jakarta.apache.org/builds/jakarta-velocity/">Download</a> |
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| <li> <a href="../install.html">Install</a> |
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| <li> <a href="../design.html">Design</a> |
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| <li> <a href="../contributors.html">Contributors</a> |
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| <li> <a href="../changes.html">ChangeLog</a> |
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| <li> <a href="../code-standards.html">Coding Standards</a> |
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| <li> <a href="../license.html">License</a> |
| </li> |
| <li> <a href="../todo.html">TODO</a> |
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| <li> <a href="http://issues.apache.org/bugzilla/enter_bug.cgi?product=Velocity">Report Issues</a> |
| </li> |
| </ul> |
| <p><strong>Community</strong></p> |
| <ul> |
| <li> <a href="../powered.html">Powered By Velocity</a> |
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| <li> <a href="http://jakarta.apache.org/site/getinvolved.html">Get Involved</a> |
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| <p><strong>Docs</strong></p> |
| <ul> |
| <li> <a href="../user-guide.html">User's Guide (English)</a> |
| </li> |
| <li> <a href="../user-guide_fi.html">User's Guide (Finnish)</a> |
| </li> |
| <li> <a href="../user-guide_fr.html">User's Guide (French)</a> |
| </li> |
| <li> <a href="../user-guide_es.html">User's Guide (Spanish)</a> |
| </li> |
| <li> <a href="../developer-guide.html">Developer's Guide</a> |
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| <li> <a href="../vtl-reference-guide.html">VTL Reference Guide</a> |
| </li> |
| <li> <a href="../specification.html">Specification</a> |
| </li> |
| <li> <a href="../api/index.html">Javadoc</a> |
| </li> |
| </ul> |
| <p><strong>Tools</strong></p> |
| <ul> |
| <li> <a href="../tools/index.html">Velocity Tools</a> |
| </li> |
| <li> <a href="../anakia.html">Anakia : XML->doc tool</a> |
| </li> |
| <li> <a href="../texen.html">Texen : text generation</a> |
| </li> |
| <li> <a href="../dvsl/index.html">DVSL : XML xformation</a> |
| </li> |
| <li> <a href="../veltag.html">Veltag : JSP taglib</a> |
| </li> |
| <li> <a href="../migration.html">Migration to Velocity</a> |
| </li> |
| <li> <a href="../devtools.html">Editors and IDEs</a> |
| </li> |
| </ul> |
| <p><strong>Comparisons</strong></p> |
| <ul> |
| <li> <a href="../ymtd/ymtd.html">YMTD</a> |
| </li> |
| <li> <a href="../differences.html">VM/WM Differences</a> |
| </li> |
| <li> <a href="../casestudy1.html">JSP vs. Velocity</a> |
| </li> |
| <li> <a href="../casestudy2.html">XMLC vs. Velocity</a> |
| </li> |
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| <p><strong>Site Translations</strong></p> |
| <ul> |
| <li> <a href="http://jakarta.apache.org/velocity/">English</a> |
| </li> |
| <li> <a href="http://www.ingrid.org/jajakarta/velocity/velocity-1.2-rc2/docs-ja/index.html">Japanese</a> |
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| <td width="80%" align="left" valign="top"> |
| <table border="0" cellspacing="0" cellpadding="2" width="100%"> |
| <tr><td bgcolor="#525D76"> |
| <font color="#ffffff" face="arial,helvetica,sanserif"> |
| <a name="Implementation"><strong>Implementation</strong></a> |
| </font> |
| </td></tr> |
| <tr><td> |
| <blockquote> |
| <table border="0" cellspacing="0" cellpadding="2" width="100%"> |
| <tr><td bgcolor="#828DA6"> |
| <font color="#ffffff" face="arial,helvetica,sanserif"> |
| <a name="The first point: Standards"><strong>The first point: Standards</strong></a> |
| </font> |
| </td></tr> |
| <tr><td> |
| <blockquote> |
| <p> |
| One of the touted advantages of JSP is that it is a "standard" and quite |
| a few people like to hold this in high regard. So much so that they |
| refuse to use any technology that is not "standard." Digging into the |
| reality of this statement reveals that the important correct terminology |
| is that JSP is a "Sun Standard Specification" and not strictly a |
| "standard." This is important because JSP is really no more "standard" |
| than Microsoft ASP or the PHP Group's PHP product. In other words, |
| whatever tool you happen to be using becomes the "standard." |
| </p> |
| <p> |
| A small group within the Java Community Process (JCP) defines what JSP |
| is. The fact of the matter is that there is a fairly high barrier to |
| joining the JCP because an NDA must be signed, the project leads must |
| approve your entry and in some cases a fee must be paid. One could even |
| stretch as far as to say that the JSP specification is really a |
| proprietary product of Sun! |
| </p> |
| <p> |
| It is important to note at this point that the primary author of this |
| document (Jon Stevens) is a member of the JSR-053 which defines the |
| Servlet and JSP specification's. |
| </p> |
| <p> |
| Inside JSR-053, it is clear that not everything is done in the open and |
| decisions are made behind closed doors. Of course the participants could |
| object, but Sun still is the binding force behind the decisions. |
| </p> |
| </blockquote> |
| </td></tr> |
| <tr><td><br/></td></tr> |
| </table> |
| <table border="0" cellspacing="0" cellpadding="2" width="100%"> |
| <tr><td bgcolor="#828DA6"> |
| <font color="#ffffff" face="arial,helvetica,sanserif"> |
| <a name="The next point: Complexity"><strong>The next point: Complexity</strong></a> |
| </font> |
| </td></tr> |
| <tr><td> |
| <blockquote> |
| <p> |
| JSP is both a specification as well as an implementation. There are |
| various corporations (as well as Open Source) implementations of the |
| specification. The JSP specification is not a particularly easy thing to |
| implement. There are many complex systems involved, some of which even |
| require special hooks into the Servlet Engine in order to obtain optimal |
| performance. |
| </p> |
| <p> |
| The JSP specification is relatively new (it is still in a 1.x phase). |
| This means that the specification also has several places in it that are |
| not as well defined as others, leaving some of the specific details to |
| be determined by the implementation. Not only does this mean that there |
| is plenty of places to make mistakes, but it also means that JSP |
| template code has the possibility of not behaving the same across |
| implementations. This makes testing JSP based applications across |
| several different containers a nightmare. Especially if there are |
| essoteric bugs (meaning bugs that only show up under extreme conditions) |
| in one and not in the other. |
| </p> |
| <p> |
| Part of the founding reason for creating the Jakarta Project and having |
| Sun release the source code to Jasper (the JSP reference implementation) |
| is to encourage vendors to adopt a single base for their source code. |
| Unfortunately, this has not happened. There is compatibility testing |
| suites available, however there is no policy in place requiring vendors |
| to pass the tests. Nor is there a place that shows vendors who do not |
| pass the tests in order to publicly humiliate them into submission. |
| </p> |
| </blockquote> |
| </td></tr> |
| <tr><td><br/></td></tr> |
| </table> |
| <table border="0" cellspacing="0" cellpadding="2" width="100%"> |
| <tr><td bgcolor="#828DA6"> |
| <font color="#ffffff" face="arial,helvetica,sanserif"> |
| <a name="The final point: Velocity"><strong>The final point: Velocity</strong></a> |
| </font> |
| </td></tr> |
| <tr><td> |
| <blockquote> |
| <p> |
| The definition of what Velocity is is set forth by the developers on the |
| project. They have created a comprehensive testing suite that is used |
| for regression testing to ensure that all changes to Velocity will not |
| break existing templates. If you or your company ever wants to join the |
| development of Velocity and help determine its direction that can be |
| done easily by simply joining a mailing list and contributing to the |
| development effort. This means that no one corporation will ever own the |
| Velocity specification and it also means that Velocity will always work |
| with your templates within any servlet engine. |
| </p> |
| </blockquote> |
| </td></tr> |
| <tr><td><br/></td></tr> |
| </table> |
| <p> |
| You make the decision. |
| </p> |
| <p> |
| <strong>[ <a href="ymtd-embedded.html">Embedded Usage</a> <- Previous | |
| Next -> <a href="./ymtd-hosting.html">Hosting</a> ] |
| </strong></p> |
| </blockquote> |
| </p> |
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| Copyright © 1999-2004, The Apache Software Foundation |
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