Validation against Spring XML files make UI hang or block

[in-fke]

First of all, I hope I am in the right project. Eclipse Source Code Repos are a mess right now.
I spent 30 minutes trying to find the proper source code and/or issue management and may have failed miserably.

Steps to reproduce

Have a Spring XML in the workspace and XML Validation on.

Some file such as

<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/security"
	xmlns:beans="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:util="http://www.springframework.org/schema/util"
	xsi:schemaLocation="http://www.springframework.org/schema/security
       http://www.springframework.org/schema/security/spring-security.xsd
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/util
       http://www.springframework.org/schema/util/spring-util.xsd">

	
</beans:beans>

Background jobs may hang with the following stack.

"Worker-307: Validation" #3649 [25120] prio=5 os_prio=0 cpu=1265.62ms elapsed=1228.92s tid=0x00000244e7bab000 nid=25120 runnable  [0x000000dcde1fc000]
   java.lang.Thread.State: RUNNABLE
        at sun.nio.ch.SocketDispatcher.read0(java.base@23.0.2/Native Method)
        at sun.nio.ch.SocketDispatcher.read(java.base@23.0.2/SocketDispatcher.java:46)
        at sun.nio.ch.NioSocketImpl.tryRead(java.base@23.0.2/NioSocketImpl.java:256)
        at sun.nio.ch.NioSocketImpl.implRead(java.base@23.0.2/NioSocketImpl.java:307)
        at sun.nio.ch.NioSocketImpl.read(java.base@23.0.2/NioSocketImpl.java:346)
        at sun.nio.ch.NioSocketImpl$1.read(java.base@23.0.2/NioSocketImpl.java:796)
        at java.net.Socket$SocketInputStream.implRead(java.base@23.0.2/Socket.java:1116)
        at java.net.Socket$SocketInputStream.read(java.base@23.0.2/Socket.java:1103)
        at java.io.BufferedInputStream.fill(java.base@23.0.2/BufferedInputStream.java:291)
        at java.io.BufferedInputStream.read1(java.base@23.0.2/BufferedInputStream.java:347)
        at java.io.BufferedInputStream.implRead(java.base@23.0.2/BufferedInputStream.java:420)
        at java.io.BufferedInputStream.read(java.base@23.0.2/BufferedInputStream.java:399)
        at sun.net.www.http.HttpClient.parseHTTPHeader(java.base@23.0.2/HttpClient.java:827)
        at sun.net.www.http.HttpClient.parseHTTP(java.base@23.0.2/HttpClient.java:759)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(java.base@23.0.2/HttpURLConnection.java:1706)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(java.base@23.0.2/HttpURLConnection.java:1615)
        at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(java.base@23.0.2/HttpURLConnection.java:3222)
        at org.eclipse.wst.internet.cache.internal.Cache.cacheResource(Cache.java:209)
        at org.eclipse.wst.internet.cache.internal.Cache.getResource(Cache.java:136)
        at org.eclipse.wst.internet.cache.internal.CacheURIResolverExtension.resolve(CacheURIResolverExtension.java:44)
        at org.eclipse.wst.common.uriresolver.internal.ExtensibleURIResolver.resolvePhysicalLocation(ExtensibleURIResolver.java:113)
        at org.eclipse.wst.xml.core.internal.validation.XMLValidator._internalResolveEntity(XMLValidator.java:652)
        at org.eclipse.wst.xml.core.internal.validation.XMLValidator$MyEntityResolver.resolveEntity(XMLValidator.java:610)
        at org.apache.xerces.impl.XMLEntityManager.resolveEntity(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaLoader.resolveDocument(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.findSchemaGrammar(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.handleStartElement(Unknown Source)
        at org.apache.xerces.impl.xs.XMLSchemaValidator.emptyElement(Unknown Source)
        at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source)
        at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source)
        at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
        at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
        at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
        at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
        at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
        at org.eclipse.wst.xml.core.internal.validation.XMLValidator.validate(XMLValidator.java:372)
        at org.eclipse.wst.xml.core.internal.validation.eclipse.Validator.validate(Validator.java:97)
        at org.eclipse.wst.xml.core.internal.validation.core.AbstractNestedValidator.validate(AbstractNestedValidator.java:283)
        at org.eclipse.wst.xml.core.internal.validation.core.AbstractNestedValidator.validate(AbstractNestedValidator.java:88)
        at org.eclipse.wst.validation.Validator$V2.validate(Validator.java:1178)
        at org.eclipse.wst.validation.internal.ValManager.validate(ValManager.java:704)
        at org.eclipse.wst.validation.internal.ValManager$1.visit(ValManager.java:665)
        at org.eclipse.wst.validation.internal.ValManager.accept(ValManager.java:783)
        at org.eclipse.wst.validation.internal.ValManager.validate(ValManager.java:669)
        at org.eclipse.wst.validation.internal.ValBuilderJob$Visitor.visit(ValBuilderJob.java:299)
        at org.eclipse.core.internal.resources.Resource.lambda$1(Resource.java:154)
        at org.eclipse.core.internal.resources.Resource$$Lambda/0x00000244a2cb32d0.visit(Unknown Source)
        at org.eclipse.core.internal.resources.Resource.lambda$0(Resource.java:122)
        at org.eclipse.core.internal.resources.Resource$$Lambda/0x00000244a2503a20.visitElement(Unknown Source)
        at org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:85)
        at org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:90)
        at org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:90)
        at org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:90)
        at org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:90)
        at org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:90)
        at org.eclipse.core.internal.watson.ElementTreeIterator.iterate(ElementTreeIterator.java:135)
        at org.eclipse.core.internal.resources.Resource.accept(Resource.java:131)
        at org.eclipse.core.internal.resources.Resource.accept(Resource.java:92)
        at org.eclipse.core.internal.resources.Resource.accept(Resource.java:154)
        at org.eclipse.core.internal.resources.Resource.accept(Resource.java:142)
        at org.eclipse.wst.validation.internal.ValBuilderJob.fullBuild(ValBuilderJob.java:219)
        at org.eclipse.wst.validation.internal.ValBuilderJob.run(ValBuilderJob.java:178)
        at org.eclipse.wst.validation.internal.ValBuilderJob.runInWorkspace(ValBuilderJob.java:126)
        at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:43)
        at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

Tested under this environment:

• Windows
• Version: 2025-06 (4.36.0) Build id: 20250605-1316
• Eclipse Web Tools Platform Common URI Resolver Framework 1.4.0.v202308161955 org.eclipse.wst.common.uriresolver

For the love of god, I was unable to find the source code of
org.eclipse.wst.internet.cache.internal.Cache
I was curious whether this class sets a proper timeout on HttpURLConnection.