Support JarUrlConnection with regexp in the SU <classpath/>

• Key: SMXCOMP-176
• Type: Improvement
• Status: Resolved
• Resolution: Fixed
• Priority: Major
• Assignee: Jean-Baptiste Onofré
• Reporter: Jean-Baptiste Onofré
• Component/s: servicemix-common
• Affects Version/s: 3.2.3

Environment

ServiceMix 3.3.1
JVM 1.5.0 Sun
Linux

Description

It's possible to extend the SU classloader using the <classpath/> tag.
Currently, the <location/> tag in classpath uses File and expects something like /path/to/my.jar.

We are going to extend this using JarUrlConnection inside the <location/> tag. Using JarUrlConnection, the user will be able to use classpath extension like :
jar:file:/path/to/my.ear!/my.jar
for example.

Moreover, we will add regexp supports for jar lookup. At the end, the user will be able to use something like that :
jar:file/path/to/my.ear!/my*.jar

Comments

[Jean-Baptiste Onofré]

For information, the <classpath/> management class is in servicemix-common. It's the ClassLoaderXmlPreprocessor.

[Guillaume Nodet]

Not sure how feasible it is to use regexp on non file based urls.

[Jean-Baptiste Onofré]

Well, I have seen the <location/> usage in the getClassLoader(SpringApplicationContext applicationContext, XmlBeanDefinitionReader reader, Document document) method.

For the <location/>, a classpath List is created and populated with location element. After that, this classpath List is transformed into a URLs array.
This transformation is made using getResource(String location) method.
The issue is that in getResource(String location), a File is used :

URI uri = root.toURI().resolve(location); // where root is a File provided in the constructor
File file = new File(uri);

I'm going to patch the getResource(String location) method to detect if the location is a JarUrlConnection or a File and return a URL.
I think that I can take the location string and apply some regexp on it (I need to investigate deeper).

[Jean-Baptiste Onofré]

I have seen that getResource(String location) method is used to load a classpath.xml file (in the SU root) too.
This classpath.xml must be remain a File. So, I will make a little patch of the preprocess() method to let the classpath.xml as a File.

Step 1 : add the support of jar: and file: classpath entries.

The path contains the getResource() changes in the ClassLoaderXmlPreprocessor and a small unit test for different kind of provided URLs.

The patch root is servicemix-core.

I resume to better support (and try the regexp support as made in Commons VFS).

[Jean-Baptiste Onofré]

A new patch that use ZipFile/ZipEntry to use regexp and generate the matching URL.

Warning : this patch is work in progress (unit test fails). I need to work on it and so it's not intended for inclusion.

[Jean-Baptiste Onofré]

Correct the issue. Now parse the URI using StringBuffer/String. Get the ZipFile and looking into entries.
Add unit test with a ear file.
Need to complete with new unit tests.

[Jean-Baptiste Onofré]

This is the first real patch release.

It includes the support of :

• file: based URL
• jar:file: based URL
• jar:file: based URL with regexp support.

Guillaume, could make a quick review on the patch and give me some feedback ?

Thanks,
Regards
JB

[Jean-Baptiste Onofré]

After dealing with Guillaume, the getResource() method should now return a list of URL.
Currently the getJarResource() supports regexp but returns only the first occurence that match. A more efficient way is to return the list of all URLs matching the regexp.

[Jean-Baptiste Onofré]

This patch now supports multi URLs.

[Jean-Baptiste Onofré]

I'm going to extend the patch to be able to use system properties.

Has we have the servicemix.home argument in the SMX startup (provided using -Dservicemix.home=), it can be interesting to use this property in the <location/> definition.

With it, we will be able to use notation like :
<classpath>
<location>${servicemix.home}/lib/ext/myjar.jar</location>
</classpath>

[Jean-Baptiste Onofré]

This patch contains :

• renaming of the methods
• adding replace method
• use system properties to replace value in location

[Jean-Baptiste Onofré]

To avoid unit test failure after applying the patch (as the test.ear file shouldn't be created using the patch file), I have commented the unit test assert around the ear exploring.

This patch should be the final one. I build a complete SMX3 distribution and make "real" tests.

[Jean-Baptiste Onofré]

The last patch contains only the change on the unit test. We need to apply both SMXCOMP-176_1 and SMXCOMP-176_2 patches (in this order).

[Jean-Baptiste Onofré]

Here is the complete patch with the commented part of the unit test.

I build SMX3 using this to perform "real" tests.

[Guillaume Nodet]

Two comments:

• I think the file:// pattern could be used with regexp too (imho this is a valid use case)
• I would avoid using a JarFile and use a JarInputStream instead, this would make all jar:xxx urls work and not only jar:file:xxx urls

[Jean-Baptiste Onofré]

Thanks for your comment Guillaume, I will submit a new patch including this.

[Jean-Baptiste Onofré]

Patch containing the last Guillaume's comment.

[Jean-Baptiste Onofré]

Another tip from Guillaume, the replaceString method can be replaced by :

for (Enumeration e = properties.propertyNames(); e.hasMoreElements() {
String key = (String)e.nextElement();
String val = properties.getProperty(key);
Matcher matcher = Pattern.compile("\\$\\{([^}]+)
}").matcher(val);
while (matcher.find()) {
String rep = System.getProperty(matcher.group(1));
if (rep != null) { val = val.replace(matcher.group(0), rep); matcher.reset(val); }
}
properties.put(key, val);

[Jean-Baptiste Onofré]

Patch commited. It will be included in the next SMX3 release.