Package org.gcube.vremanagement.executor.utils

Class ReflectionUtility

java.lang.Object

org.gcube.vremanagement.executor.utils.ReflectionUtility

public class ReflectionUtility
extends Object

Got from https://stackoverflow.com/questions/520328/can-you-find-all-classes-in-a-package-using-reflection#answer-22462785 The method first gets the current ClassLoader. It then fetches all resources that contain said package and iterates of these URLs. It then creates a URLConnection and determines what type of URL we have. It can either be a directory (FileURLConnection) or a directory inside a jar or zip file (JarURLConnection). Depending on what type of connection we have two different methods will be called. First lets see what happens if it is a FileURLConnection. It first checks if the passed File exists and is a directory. If that's the case it checks if it is a class file. If so a Class object will be created and put in the List. If it is not a class file but is a directory, we simply iterate into it and do the same thing. All other cases/files will be ignored. If the URLConnection is a JarURLConnection the other private helper method will be called. This method iterates over all Entries in the zip/jar archive. If one entry is a class file and is inside of the package a Class object will be created and stored in the ArrayList. After all resources have been parsed it (the main method) returns the ArrayList containing all classes in the given package, that the current ClassLoader knows about. If the process fails at any point a ClassNotFoundException will be thrown containing detailed information about the exact cause.

Constructor Summary

Constructors

Constructor	Description
ReflectionUtility()

Method Summary

Modifier and Type	Method	Description
static List<Class<?>>	getClassesForPackage(Package packageObject)
static List<Class<?>>	getClassesForPackage(String pckgname)	Attempts to list all the classes in the specified package as determined by the context class loader

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ReflectionUtility

public ReflectionUtility()

Method Details

getClassesForPackage

public static List<Class<?>> getClassesForPackage(Package packageObject)
                                           throws ClassNotFoundException

Throws:

ClassNotFoundException

getClassesForPackage

public static List<Class<?>> getClassesForPackage(String pckgname)
                                           throws ClassNotFoundException

Attempts to list all the classes in the specified package as determined by the context class loader

Parameters:

pckgname - the package name to search

Returns:

a list of classes that exist within that package

Throws:

ClassNotFoundException - if something went wrong