Tweaking jetty-jsp-9.1.1.B60.25.p2.jar to support hightide-on-OSGi.
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Fork of https://svn.codehaus.org/jetty/jsp/tags/jetty-jsp-9.1.1.B60.25.p2/
Small modifications to be able to use the jasper-jetty bundle from OSGi.
Please refer to https://bugs.eclipse.org/bugs/show_bug.cgi?id=289404

Here is the experimental project that takes advantage of this fork:
http://github.com/hmalphettes/osgi-webapp-simple


Summary of the changes:

Import-Package modifications:
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    All com.sun and sun.misc Package-Import optional.
    ------------------------------------------------
com.sun.org.apache.xml.internal*, com.sun.org.apache.xpath.internal*
Used by the jstl xpath engine.
Jasper extends the xpath engine of the jdk to add support to retrieve native java objects on the xml tree.
Eclipse-PDE complains that those imports can not be done due to restrictions on rt.jar.
Jan Bartel's workaround consists of placing those packages as part of the system property "org.osgi.framework.system.packages":
http://docs.codehaus.org/display/JETTY/OSGi+Tips

However I was able to execute succesffully the corresponding jstl tags without this workaround.

com.sun.org.apache.xalan.internal.res
None of the sources are directly importing this package. Making it optional does not hurt.


    All jdt and ant Package-Import optional.
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Jasper's dynamically select a compiler according to what it can find on the classpath. It does not require both.

Additional Patches in src/main/patches:
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    JDTJavaCompiler:
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Support for using the bundle org.eclipse.jdt.core.compiler.batch-3.2.0 and more recent.
core-3.1.1 which is the only supported version of eclipse-compiler without this patch is a problem as it requires equinox and eclipse-rcp to be loaded. The JDTJavaCompiler patched still supports core-3.1.1.

    ParserUtils:
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Cherry-pick a static method "setEntityResolver" that has been added to more recent version of Jasper:
https://jsp.dev.java.net/source/browse/jsp/trunk/impl/src/main/java/org/apache/jasper/xmlparser/ParserUtils.java
exact revision: https://jsp.dev.java.net/source/browse/jsp?rev=955&view=rev

This is used to be able to override the default resolution of the dtd when tld files are parsed.
The dtd resolution relies on ParserUtils.class.getResource("/javax/servlet/resources/*.dtd").
That does not work in OSGI as the dtd files are in packaged in a separate bundle and each bundle has a separate classloader.
This method allow us to customize the resolution.