Java Language Loading same-name resource from multiple JARs


Example

Resource with same path and name may exist in more than one JAR file on the classpath. Common cases are resources following a convention or that are part of a packaging specification. Examples for such resources are

  • META-INF/MANIFEST.MF
  • META-INF/beans.xml (CDI Spec)
  • ServiceLoader properties containing implementation providers

To get access to all of these resources in different jars, one has to use a ClassLoader, which has a method for this. The returned Enumeration can be conveniently converted to a List using a Collections function.

Enumeration<URL> resEnum = MyClass.class.getClassLoader().getResources("META-INF/MANIFEST.MF");
ArrayList<URL> resources = Collections.list(resEnum);