[COMPRESS-627] Pack200 causes a 'archive.3E' error if it’s not in the system class loader.

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.21
• Fix Version/s: 1.22

Environment

anatawa12@anatawa12-book:~/commons-compress-pack200-test $ neofetch --off --stdout
[e-mail]
---------------------------------------------------
OS: macOS 12.6 21G115 arm64
Host: MacBookPro18,4
Kernel: 21.6.0
Uptime: 11 days, 8 hours, 58 mins
Packages: 199 (brew)
Shell: zsh 5.8.1
Resolution: 1800x1169
DE: Aqua
WM: Quartz Compositor
WM Theme: Blue (Light)
Terminal: iTerm2
Terminal Font: Monaco 12
CPU: Apple M1 Max
GPU: Apple M1 Max
Memory: 10849MiB / 65536MiB

anatawa12@anatawa12-book:~/commons-compress-pack200-test $ java -version
openjdk version "1.8.0_332"
OpenJDK Runtime Environment (Zulu 8.62.0.19-CA-macos-aarch64) (build 1.8.0_332-b09)
OpenJDK 64-Bit Server VM (Zulu 8.62.0.19-CA-macos-aarch64) (build 25.332-b09, mixed mode)

• Assignee: Unassigned
• Reporter: anatawa12
• Created: 03/Oct/22 00:34
• Updated: 04/Oct/22 13:04
• Resolved: 04/Oct/22 13:04

Description

import org.apache.commons.compress.java.util.jar.Pack200;
import java.lang.reflect.Method;
import java.net.URLClassLoader;
import java.net.URL;
import java.io.File;

class Main {
  public static void main(String[] args) throws Throwable {
    URLClassLoader ucl = new URLClassLoader(new URL[] {
      new File(".").toURI().toURL(),
      new File("commons-compress-1.21.jar").toURI().toURL(),
    }, null);

    System.out.println("=== Unpacker ===");
    Method method;
    try {
      method = ucl.loadClass("InClassLoaderClass").getDeclaredMethod("unpacker");
      method.setAccessible(true);
      method.invoke(null);
    } catch (Throwable t) {
      t.printStackTrace();
    }

    System.out.println("=== Packer ===");
    try {
      method = ucl.loadClass("InClassLoaderClass").getDeclaredMethod("packer");
      method.setAccessible(true);
      method.invoke(null);
    } catch (Throwable t) {
      t.printStackTrace();
    }
  }
}

class InClassLoaderClass {
  public static void unpacker() {
    Pack200.newUnpacker();
  }
  public static void packer() {
    Pack200.newPacker();
  }
}

execute this code (same as attached Main.java) with ClassLoaderClass.class (compiled code of this file) and commons-compress-1.21.jar is on working directory will cause the following error:

anatawa12@anatawa12-book:~/commons-compress-pack200-test $ javac -cp commons-compress-1.21.jar Main.java && java Main
=== Unpacker ===
java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at Main.main(Main.java:19)
Caused by: java.lang.Error: archive.3E
	at org.apache.commons.compress.java.util.jar.Pack200$2.run(Pack200.java:100)
	at java.security.AccessController.doPrivileged(Native Method)
	at org.apache.commons.compress.java.util.jar.Pack200.newUnpacker(Pack200.java:91)
	at InClassLoaderClass.unpacker(Main.java:37)
	... 5 more
Caused by: java.lang.ClassNotFoundException: org.apache.commons.compress.harmony.unpack200.Pack200UnpackerAdapter
	at java.net.URLClassLoader.findClass(URLClassLoader.java:387)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:419)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:352)
	at org.apache.commons.compress.java.util.jar.Pack200$2.run(Pack200.java:98)
	... 8 more
=== Packer ===
java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at Main.main(Main.java:28)
Caused by: java.lang.Error: archive.3E
	at org.apache.commons.compress.java.util.jar.Pack200$1.run(Pack200.java:72)
	at java.security.AccessController.doPrivileged(Native Method)
	at org.apache.commons.compress.java.util.jar.Pack200.newPacker(Pack200.java:61)
	at InClassLoaderClass.packer(Main.java:40)
	... 5 more
Caused by: java.lang.ClassNotFoundException: org.apache.commons.compress.harmony.pack200.Pack200PackerAdapter
	at java.net.URLClassLoader.findClass(URLClassLoader.java:387)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:419)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:352)
	at org.apache.commons.compress.java.util.jar.Pack200$1.run(Pack200.java:70)
	... 8 more

In src/main/java/org/apache/commons/compress/java/util/jar/Pack200.java, Packer/Unpacker implementaion is loaded from ClassLoader.getSystemClassLoader().
However, Apache commons compress may be loaded from other class loaders in many environments (e.g. Gradle).