Performance optimization

[zenglzh]

Change the acquisition of system attributes to static variables to reduce congestion in high concurrency environments. The Boolean.getBoolean method will call Hashtable to obtain system propertys ,and will lock.

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[bdemers]

Approved with a minor suggestion.
If you don't have time to tweak it don't worry about out ;)

[bdemers]

nit: you may want to move this to just under the ALLOW_BACKSLASH def above in this file.

I only mention this because it took my brain a sec to realize there was an IS_ prefix.
This isn't critical, I probably just need more caffeine 🤣

[zenglzh]

Through the system pressure test, this lock has a great impact on our system performance.
Can you put ALLOW_ BACKSLASH, as a global static variable, can be reset by a static method, such as:

//WebUtils.java
public static void retrieveSystemProperties(){
    WebUtils.allowBackslash = Boolean.getBoolean(ALLOW_BACKSLASH);
}

This method is slightly modified, but the test case needs to be modified.

[bdemers]

@zenglzh I'm guessing something like what you are suggesting is the easiest path forward.

Possibly making it package protected in WebUtils:

static void reloadSystemProperties(){
    allowBackslash = Boolean.getBoolean(ALLOW_BACKSLASH);
}

There is another test that checks the backslash logic too, but IIRC, that one is written in Groovy, and will allow access to that method anyway.

[zenglzh]

Yes,@bdemers . by the way, can we delete the "ALLOW_BACKSLASH" attribute?Use File.separatorChar instead. such as:

    //@see org.apache.catalina.webresources.AbstractFileResourceSet#normalize  in Tomcat trunk
    public static String normalize(String path) {
        return normalize(path, File.separatorChar == '\\');
    }

[bdemers]

Even on windows, you may want to block the use of backslashes, as they may be used to escape other chars.
But there are systems out there that are currently allowing backslashes. I think allowing them to opt-into is still probably our best bet.
Your idea for parsing the value once, allows for the current behavior and fixes the perf issue you are seeing.

[bdemers]

nit: this static var should be upper case

[zenglzh]

I can't handle the build in openj9 check 🤕。Please anybody help me ... ☕

[fpapon]

I can't handle the build in openj9 check face_with_head_bandage。Please anybody help me ... coffee

@zenglzh it happen only on MacOS so I would say that it's not mandatory to fix it as it's ok on Jenkins full workflow.

[fpapon]

@lprimak can you redo a review?

[lprimak]

@fpapon done

outdated

[lprimak]

Another nit :) Can you redo this PR with just one commit, with a good description?
The bunch of "Update WebUtils.java" is not descriptive enough.

git reset --soft origin/main
git commit
git push --force

Last one I promise :)

[lprimak]

@zenglzh never mind I did it for you :)

[lprimak]

@zenglzh Thanks for your contribution, we appreciate it!