lorenzoongithub / nudge4j

Get inside your JVM

nudge4j ·

nudge4j is a tiny piece of code to help great developers understand code better, debug less, have more fun.

Overview

With nudge4j you can:

• control your Java application from the browser, as if the browser was a smarter remote control.
• send code from the browser to run on the JVM,
• experiment with live code.

To use nudge4j, just add less than 10 lines of code in your program.

Issues

Report any issue using GitHub and use notifications to track progress on them.

Contributing

Want to hack on this project? Any kind of contribution is welcome! But I am particularly interested in Nashorn/JavaScript samples to add in the example section.

License

This project is licensed under the MIT license.

nudge4j's Issues

links are dead

any chance of fixing the links?

"get all classes" doesen't work - gives FileNotFoundException

I get
The link points to http://localhost:5050/js?code=load(%27https%3A%2F%2Florenzoongithub.github.io%2Fnudge4j%2Ftwigs%2Fget.all.classes.js%27)%3BgetAllClasses(%7BskipJDK%3Afalse%7D)

err::java.lang.RuntimeException: java.io.FileNotFoundException: https://lorenzoongithub.github.io/nudge4j/twigs/get.all.classes.js
at jdk.nashorn.internal.runtime.ScriptRuntime.apply(ScriptRuntime.java:397)
at jdk.nashorn.api.scripting.ScriptObjectMirror.call(ScriptObjectMirror.java:117)
at jdk.nashorn.internal.runtime.linker.JSObjectLinker.jsObjectScopeCall(JSObjectLinker.java:238)
at jdk.nashorn.internal.scripts.Script$17$^eval_.:program(:1)

obfuscated base64 code looks malicious

Ciao Lorenzo!
Thanks for sharing nudge4j which is a pretty cool idea!
Me and my friends were discussing about the implication of the copy-pasting base64 code into an application as shown in https://lorenzoongithub.github.io/nudge4j.
I found your gist showing (probably) the same code not encoded:

/** nudge4j **/
{
    int      nudge4j_port = 8080; /* http port for Nudge Server */
    Object[] nudge4j_args = {}; /* optional arguments here {} */
    try {
        java.net.URLClassLoader nudge4j_loader = new java.net.URLClassLoader(
            new java.net.URL[] { new java.net.URL("http://nudge4j.appspot.com/onthecloud/nudge4j.jar") });
        nudge4j_loader.loadClass("nudge4j.HttpServer").getMethod("start", int.class, Object[].class)
            .invoke(null, nudge4j_port, nudge4j_args);
        nudge4j_loader.close();
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}
/** end nudge4j **/

so essentially your code spawn the webserver and execute the content of the remot jar http://nudge4j.appspot.com/onthecloud/nudge4j.jar

How comes you have decided to suggest to copy paste the Base64 code instead of the plaintext version?
What about posting plaintext code and sharing the jar on public (free for open-source project) maven repository?

Not usable to inspect a running application - no non-JVM classes seems to be available

I have tried a lot but I can't access any of my own classes from nudge4j.

That makes it useless to inspect a running application - which is what I got the impression would be possible.

Even though I have lots of classses available on the class path:
http://localhost:5050/js?code=java.lang.System.getProperty(%27java.class.path%27)

I still cant instantiate them, and the (repaired) 'get all classes (exclude JDKs)' links
http://localhost:5050/js?code=load(%27https%3A%2F%2Florenzoongithub.github.io%2Fnudge4j%2Ftwigs%2Fdump.all.classes.js%27)%3BdumpAllClasses(%7BskipJDK%3Atrue%7D)

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