[HADOOP-13410] RunJar adds the content of the jar twice to the classpath - ASF JIRA

Voters

Watch issue

Watchers

Create sub-task

Link

Clone

Update Comment Author

Replace String in Comment

Update Comment Visibility

Delete Comments

XML

Word

Printable

JSON

Details

Type: Bug
Status: Resolved
Priority: Major
Resolution: Fixed
Affects Version/s: None
Fix Version/s: 3.0.0-alpha1
Component/s: util
Labels:
None

Description

Today when you run a "hadoop jar" command, the jar is unzipped to a temporary location and gets added to the classloader.

However, the original jar itself is still added to the classpath.

      List<URL> classPath = new ArrayList<>();
      classPath.add(new File(workDir + "/").toURI().toURL());
      classPath.add(file.toURI().toURL());
      classPath.add(new File(workDir, "classes/").toURI().toURL());
      File[] libs = new File(workDir, "lib").listFiles();
      if (libs != null) {
        for (File lib : libs) {
          classPath.add(lib.toURI().toURL());
        }
      }

As a result, the contents of the jar are present in the classpath twice and are completely redundant. Although this does not necessarily cause correctness issues, some stricter code written to require a single presence of files may fail.

I cannot think of a good reason why the jar should be added to the classpath if the unjarred content was added to it. I think we should remove the jar from the classpath.