[Solved] what this line of code mean….new URLClassLoader(new URL[0],getClass().getClassLoader()); [closed]

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I want to know what is purpose of new URLClassLoader(new URL[0],getClass().getClassLoader());

It means: make a new URLClassloader that loads classes / resources from an empty array of URLs, and has this classes classloader as the parent.

The resulting classloader object is then discarded.

So I think this is just testing to see if the application is permitted to create a classloader.

The class JVM is not one that I recognize. I don’t know what that is about.

what happens if this code throw exception

Nothing happens apart from the obvious. If the exception is a SecurityException you wrap it and throw it as a different exception. Otherwise the exception propagates.

The InsufficientPermissionDetected class may be a Hudson or Jenkins class. If that is the case, examine the rest of the Hudson or Jenkins codebase to see how it handles the exception.

[how do I] grant permission if it throws SecurityException

It depends on what platform the code is executed on.

  • If you are running on non-sandboxed Java JVM, you should already have permission … to do everything.

  • If you are running on a sandboxed Java JVM, then the permission must be granted by the sandboxing mechanism. For example, with a trusted JAR file:

    • The JAR must be signed with a CERT that the user / user’s JVM trusts.
    • The code in the JAR file is then permitted to access controlled APIs as per the policy file that is in force.

    For more details, start by reading “Trail: Security Features in Java SE”

  • If you are running on Android …. not sure.

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solved what this line of code mean….new URLClassLoader(new URL[0],getClass().getClassLoader()); [closed]