例子二:通過Xalan 1.2,使用XSLT轉換XML
做為第二個例子,我們使用了Xalan-java的XSLT引擎,這個引擎來自於APACHE的XML項目,使用這個程序,我們能夠使用XSL轉換XML源文件。這將極大的方便我們處理文檔和進行內容管理。
開始之前,我們需要將xerces.jar 和 xalan.jar文件放入java.class.path目錄下(這兩個文件包含在Xalan-Java 1.2 中,可以從xml.apache.org處下載)。
PHP程序如下:
函數xslt_transform()以XML和XSL文件為參數,形式可為文件名(如:foo.xml)或URL(如:http://localhost/foo.xml)。
<?php
function xslt_transform($xml,$xsl) {
// Create a XSLTProcessorFactory object. XSLTProcessorfactory is a Java
// class which manufactures the processor for performing transformations.
$XSLTProcessorFactory = new java("org.apache.xalan.xslt.XSLTProcessorFactory");
// Use the XSLTProcessorFactory method getProcessor() to create a
// new XSLTProcessor object.
$XSLTProcessor = $XSLTProcessorFactory->getProcessor();
// Use XSLTInputSource objects to provide input to the XSLTProcessor
// process() method for transformation. Create objects for both the
// xml source as well as the XSL input source. Parameter of
// XSLTInputSource is (in this case) a 'system identifier' (URI) which
// can be an URL or filename. If the system identifier is an URL, it
// must be fully resolved.
$xmlID = new java("org.apache.xalan.xslt.XSLTInputSource", $xml);
$stylesheetID = new java("org.apache.xalan.xslt.XSLTInputSource", $xsl);
// Create a stringWriter object for the output.
$stringWriter = new java("java.io.StringWriter");
// Create a ResultTarget object for the output with the XSLTResultTarget
// class. Parameter of XSLTResultTarget is (in this case) a 'character
// stream', which is the stringWriter object.
$resultTarget = new java("org.apache.xalan.xslt.XSLTResultTarget", $stringWriter);
// Process input with the XSLTProcessors' method process(). This
// method uses the XSL stylesheet to transform the XML input, placing
// the result in the result target.
$XSLTProcessor->process($xmlID,$stylesheetID,$resultTarget);
// Use the stringWriters' method toString() to
// return the buffer's current value as a string to get the
// transformed result.
$result = $stringWriter->toString();
$stringWriter->close();
return($result);
}
?>
函數定義好後,我們就可以調用它了,在下面的例程中,變量$xml指向一個URL字符串,$xsl也是如此。這個例子將顯示5個最新的phpbuilder.com文章標題。
<?php
$xml = "http://www.phpbuilder.com/rss_feed.php?type=articles&limit=5";
$xsl = "http://www.soeterbroek.com/code/xml/rss_html.xsl";
$out = xslt_transform($xml,$xsl);
echo $out;
?>
如果你在本地機上運行程序,必須確保你的函數參數指向正確的文件名。
<?php
$xml = "/web/htdocs/xml_java/rss_feed.xml";
$xsl = "/web/htdocs/xml_java/rss_html.xsl";
$out = xslt_transform($xml,$xsl);
echo $out;
?>
雖然這種效果我們可以通過其它方法實現,或許那些方法更好,但這個例子能讓你對PHP調用JAVA類有一個更好的了解。
教程結束了,希望你能夠從這篇教程中學到點東西,以下是一些你用得到的鏈接:
http://www.php4win.de ~ A great Win32 distribution of PHP
http://www.javasoft.com ~ Sun's Java release
http://www.jars.com ~ Start searching for handy Java classes
http://www.gamelan.com ~ More Java classes
http://www.technetcast.com/tnc_play_stream.html?stream_id=400 ~ Sam Ruby about PHP and Java integration at Open Source Convention 2000 (audio)
http://xml.apache.org ~ Apache XML Project
http://www.phpbuilder.com/columns/justin20001025.php3 ~ Transforming XML with XSL using Sablotron