Application cannot start for exception 'zip file closed'

[pj892031]

Our application is split into two JARs (The first contains the spring boot launcher and our classes. The second file contains just 3rd party libraries) to be possible to share libraries between multiple applications to mitigate data transfer etc.:

jar lite.jar:

+BOOT-INF
| + classes (our classes and resources)
| + lib (our libraries - not the 3rd party)
| + classpath.idx
| + layers.idx
+ META-INF
| + MANIFEST.MF
+ org (spring boot launcher)

jar lite-lib.jar

+ BOOT-INF
| + lib (3rd party libraries)
+ META-INF
  + MANIFEST.MF (empty manifest)

We run this application with command like java -cp lite.jar -Dloader.path=lite-lib.jar org.springframework.boot.loader.PropertiesLauncher

Our JDK:

java version "1.8.0_321"
Java(TM) SE Runtime Environment (build 8.0.7.5 - pmz6480sr7fp5-20220208_01(SR7 FP5))
IBM J9 VM (build 2.9, JRE 1.8.0 z/OS s390x-64-Bit Compressed References 20220104_19630 (JIT enabled, AOT enabled)
OpenJ9   - 2d4c7d9
OMR      - 59845b7
IBM      - 3c151c1)
JCL - 20220120_01 based on Oracle jdk8u321-b07

Since version 2.6.9 we randomly got this exception:

java.lang.reflect.InvocationTargetException
.at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
.at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:90)
.at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:55)
.at java.lang.reflect.Method.invoke(Method.java:508)
.at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:49)
.at org.springframework.boot.loader.Launcher.launch(Launcher.java:108)
.at org.springframework.boot.loader.Launcher.launch(Launcher.java:58)
.at org.springframework.boot.loader.PropertiesLauncher.main(PropertiesLauncher.java:467)
Caused by: java.lang.IllegalStateException: zip file closed
.at org.springframework.boot.loader.jar.JarFile.ensureOpen(JarFile.java:383)
.at org.springframework.boot.loader.jar.JarFile.getEntry(JarFile.java:269)
.at org.springframework.boot.loader.jar.JarFileWrapper.getEntry(JarFileWrapper.java:82)
.at org.springframework.boot.loader.LaunchedURLClassLoader.lambda$definePackage$0(LaunchedURLClassLoader.java:225)
.at org.springframework.boot.loader.LaunchedURLClassLoader$$Lambda$10/0x00000000d8525970.run(Unknown Source)
.at java.security.AccessController.doPrivileged(AccessController.java:774)
.at org.springframework.boot.loader.LaunchedURLClassLoader.definePackage(LaunchedURLClassLoader.java:217)
.at org.springframework.boot.loader.LaunchedURLClassLoader.definePackageIfNecessary(LaunchedURLClassLoader.java:199)
.at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:140)
.at java.lang.ClassLoader.loadClass(ClassLoader.java:873)
....
.at ch.qos.logback.classic.spi.TurboFilterList.getTurboFilterChainDecision(TurboFilterList.java:60)
.at ch.qos.logback.classic.LoggerContext.getTurboFilterChainDecision_0_3OrMore(LoggerContext.java:269)
.at ch.qos.logback.classic.Logger.filterAndLog_0_Or3Plus(Logger.java:373)
.at ch.qos.logback.classic.Logger.error(Logger.java:522)
....

It seems that the reason is the commit b42f056:

It collects references of nested JARs and then closes their streams if the main is closing, see:

spring-boot/spring-boot-project/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java

Line 99 in 24c2ed3

private final List<JarFile> nestedJars = Collections.synchronizedList(new ArrayList<>());

spring-boot/spring-boot-project/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java

Lines 335 to 347 in 24c2ed3

	private JarFile createJarFileFromFileEntry(JarEntry entry) throws IOException {
	if (entry.getMethod() != ZipEntry.STORED) {
	throw new IllegalStateException(
	"Unable to open nested entry '" + entry.getName() + "'. It has been compressed and nested "
	+ "jar files must be stored without compression. Please check the "
	+ "mechanism used to create your executable jar file");
	}
	RandomAccessData entryData = this.entries.getEntryData(entry.getName());
	JarFile nestedJar = new JarFile(this.rootFile, this.pathFromRoot + "!/" + entry.getName(), entryData,
	JarFileType.NESTED_JAR);
	this.nestedJars.add(nestedJar);
	return nestedJar;
	}

spring-boot/spring-boot-project/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java

Lines 362 to 379 in 24c2ed3

	public void close() throws IOException {
	if (this.closed) {
	return;
	}
	synchronized (this) {
	super.close();
	if (this.type == JarFileType.DIRECT) {
	this.rootFile.close();
	}
	if (this.wrapper != null) {
	this.wrapper.close();
	}
	for (JarFile nestedJar : this.nestedJars) {
	nestedJar.close();
	}
	this.closed = true;
	}
	}

I guess the problem is in synchronization between threads. The code contains synchronization blocks for elementary operation, but cannot detect if a different thread is trying to read data meanwhile.

Once I remove this part of the code (closing of nestedJar) I was not able to simulate this case again.

spring-boot/spring-boot-project/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java

Lines 374 to 376 in 24c2ed3

	for (JarFile nestedJar : this.nestedJars) {
	nestedJar.close();
	}

If I am right, those streams shouldn't be closed. One way could be to use ie. ByteArrayInputStream as a buffer and takes care just of the input streams reading the data.

[wilkinsona]

This may be a duplicate of #31853.

[philwebb]

Having dug into #31853 a bit more I'm pretty sure this is a duplicate. @pj892031 If at all possible, once build 1110 if green, could you try the latest SNAPSHOT build and see if the issue is fixed?

[pj892031]

I tested that with the snapshot version and could not reproduce the bug. It seems to be solved. Thank you.