Java Doc for EnvironmentCheck.java in  » XML » xalan » org » apache » xalan » xslt » Java Source Code / Java DocumentationJava Source Code and Java Documentation

Usage-command line: java org.apache.xalan.xslt.EnvironmentCheck [-out outFile]

Usage-from program: boolean environmentOK = (new EnvironmentCheck()).checkEnvironment(yourPrintWriter);

Usage-from stylesheet:

 <?xml version="1.0"?>
 <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"
 xmlns:xalan="http://xml.apache.org/xalan"
 exclude-result-prefixes="xalan">
 <xsl:output indent="yes"/>
 <xsl:template match="/">
 <xsl:copy-of select="xalan:checkEnvironment()"/>
 </xsl:template>
 </xsl:stylesheet>
 

Xalan users reporting problems are encouraged to use this class to see if there are potential problems with their actual Java environment before reporting a bug. Note that you should both check from the JVM/JRE's command line as well as temporarily calling checkEnvironment() directly from your code, since the classpath may differ (especially for servlets, etc).

Also see http://xml.apache.org/xalan-j/faq.html

Note: This class is pretty simplistic: results are not necessarily definitive nor will it find all problems related to environment setup. Also, you should avoid calling this in deployed production code, both because it is quite slow and because it forces classes to get loaded.

Note: This class explicitly has very limited compile-time dependencies to enable easy compilation and usage even when Xalan, DOM/SAX/JAXP, etc. are not present.

Note: for an improved version of this utility, please see the xml-commons' project Which utility which does the same kind of thing but in a much simpler manner.

Note that this class is not advanced enough to tell you everything about the environment that affects Xalan, and sometimes reports errors that will not actually affect Xalan's behavior.

Worker method called from various places.

Various system and CLASSPATH, etc.

Copy of writeEnvironmentReport that creates a Node suitable for other processing instead of a properties-like text output.

Note that this class is not advanced enough to tell you everything about the environment that affects Xalan, and sometimes reports errors that will not actually affect Xalan's behavior. Currently, it very simplistically checks the JVM's environment for some basic properties and logs them out; it will report a problem if it finds a setting or .jar file that is likely to cause problems.

Advanced users can peruse the code herein to help them investigate potential environment problems found; other users may simply send the output from this tool along with any bugs they submit to help us in the debugging process.

Worker method called from various places.

Various system and CLASSPATH, etc. properties are put into the hash as keys with a brief description of the current state of that item as the value. Any serious problems will be put in with a key that is prefixed with #ERROR 'ERROR.' so it stands out in any resulting report; also a key with just that constant will be set as well for any error.

Note that some legitimate cases are flaged as potential errors - namely when a developer recompiles xalan.jar on their own - and even a non-error state doesn't guaruntee that everything in the environment is correct. But this will help point out the most common classpath and system property problems that we've seen.

Command line entrypoint; Sets output and calls EnvironmentCheck.checkEnvironment(PrintWriter) .

This dumps a simple header and then each of the entries in the Hashtable to our PrintWriter; it does special processing for entries that are .jars found in the classpath.