[build] provision OpenJDK before Java.Interop Prepare - #11442

Merged
simonrozsival merged 3 commits into
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jonathanpeppers/jubilant-robot
May 22, 2026
Merged

[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
mainfrom
jonathanpeppers/jubilant-robot

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@jonathanpeppers

@jonathanpeppersjonathanpeppers commented May 21, 2026

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Context

PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.

Symptom

On a fresh macOS hosted agent (today's main CI build 14159635):

warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:

FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.

Fix

Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.

The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.

@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI review requested due to automatic review settings May 21, 2026 20:04
CopilotAI reviewed May 21, 2026
View reviewed changes

CopilotAI left a comment

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Pull request overview

This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.

Changes:

  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.

Comment threadbuild-tools/scripts/DotNet.targets Outdated
jonathanpeppersand others added 2 commits May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival merged commit 0320b81 into mainMay 22, 2026
3 checks passed
@simonrozsival
simonrozsival deleted the jonathanpeppers/jubilant-robot branch May 22, 2026 12:16
@github-actionsgithub-actionsBot locked and limited conversation to collaborators Jun 22, 2026
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

Skip to content
[build] provision OpenJDK before Java.Interop Prepare - #11442
Merged
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
May 22, 2026
Merged
[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
Conversation
@jonathanpeppers
@jonathanpeppersjonathanpeppers
commented
May 21, 2026

Copy link


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Member
Context
PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.
Symptom
On a fresh macOS hosted agent (today's main CI build 14159635):
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.
Fix
Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.
The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.
@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 20:04
CopilotAI
reviewed
May 21, 2026
View reviewed changes
CopilotAI
left a comment


Copy link


Copy Markdown

Contributor
Choose a reason for hiding this comment

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Pull request overview
This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.
Changes:
  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.
Comment threadbuild-tools/scripts/DotNet.targets
Outdated

jonathanpeppersand others
added 2 commits
May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival
merged commit 0320b81
into
mainMay 22, 2026

3 checks passed

@simonrozsival
simonrozsival
deleted the

jonathanpeppers/jubilant-robot

branch
May 22, 2026 12:16
@github-actionsgithub-actionsBot
locked and limited conversation to collaborators
Jun 22, 2026
Sign up for freeto subscribe to this conversation on GitHub.
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@simonrozsivalsimonrozsivalsimonrozsival approved these changes

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3 participants

@jonathanpeppers@simonrozsival

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
[build] provision OpenJDK before Java.Interop Prepare - #11442
Merged
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
May 22, 2026
Merged
[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
Conversation
@jonathanpeppers
@jonathanpeppersjonathanpeppers
commented
May 21, 2026

Copy link


Copy Markdown

Member
Context
PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.
Symptom
On a fresh macOS hosted agent (today's main CI build 14159635):
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.
Fix
Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.
The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.
@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 20:04
CopilotAI
reviewed
May 21, 2026
View reviewed changes
CopilotAI
left a comment


Copy link


Copy Markdown

Contributor
Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Pull request overview
This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.
Changes:
  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.
Comment threadbuild-tools/scripts/DotNet.targets
Outdated

jonathanpeppersand others
added 2 commits
May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival
merged commit 0320b81
into
mainMay 22, 2026

3 checks passed

@simonrozsival
simonrozsival
deleted the

jonathanpeppers/jubilant-robot

branch
May 22, 2026 12:16
@github-actionsgithub-actionsBot
locked and limited conversation to collaborators
Jun 22, 2026
Sign up for freeto subscribe to this conversation on GitHub.
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Sign in.


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Applies to this pull request for everyone.Learn more about Copilot code review.
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@simonrozsivalsimonrozsivalsimonrozsival approved these changes

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@jonathanpeppers@simonrozsival

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
[build] provision OpenJDK before Java.Interop Prepare - #11442
Merged
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
May 22, 2026
Merged
[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
Conversation
@jonathanpeppers
@jonathanpeppersjonathanpeppers
commented
May 21, 2026

Copy link


Copy Markdown

Member
Context
PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.
Symptom
On a fresh macOS hosted agent (today's main CI build 14159635):
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.
Fix
Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.
The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.
@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 20:04
CopilotAI
reviewed
May 21, 2026
View reviewed changes
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Pull request overview
This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.
Changes:
  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.
Comment threadbuild-tools/scripts/DotNet.targets
Outdated

jonathanpeppersand others
added 2 commits
May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival
merged commit 0320b81
into
mainMay 22, 2026

3 checks passed

@simonrozsival
simonrozsival
deleted the

jonathanpeppers/jubilant-robot

branch
May 22, 2026 12:16
@github-actionsgithub-actionsBot
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Jun 22, 2026
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@simonrozsivalsimonrozsivalsimonrozsival approved these changes

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@jonathanpeppers@simonrozsival

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
[build] provision OpenJDK before Java.Interop Prepare - #11442
Merged
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
May 22, 2026
Merged
[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
Conversation
@jonathanpeppers
@jonathanpeppersjonathanpeppers
commented
May 21, 2026

Copy link


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Member
Context
PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.
Symptom
On a fresh macOS hosted agent (today's main CI build 14159635):
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.
Fix
Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.
The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.
@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 20:04
CopilotAI
reviewed
May 21, 2026
View reviewed changes
CopilotAI
left a comment


Copy link


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Contributor
Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Pull request overview
This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.
Changes:
  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.
Comment threadbuild-tools/scripts/DotNet.targets
Outdated

jonathanpeppersand others
added 2 commits
May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival
merged commit 0320b81
into
mainMay 22, 2026

3 checks passed

@simonrozsival
simonrozsival
deleted the

jonathanpeppers/jubilant-robot

branch
May 22, 2026 12:16
@github-actionsgithub-actionsBot
locked and limited conversation to collaborators
Jun 22, 2026
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Applies to this pull request for everyone.Learn more about Copilot code review.
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@simonrozsivalsimonrozsivalsimonrozsival approved these changes

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3 participants

@jonathanpeppers@simonrozsival

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
[build] provision OpenJDK before Java.Interop Prepare - #11442
Merged
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
May 22, 2026
Merged
[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
Conversation
@jonathanpeppers
@jonathanpeppersjonathanpeppers
commented
May 21, 2026

Copy link


Copy Markdown

Member
Context
PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.
Symptom
On a fresh macOS hosted agent (today's main CI build 14159635):
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.
Fix
Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.
The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.
@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 20:04
CopilotAI
reviewed
May 21, 2026
View reviewed changes
CopilotAI
left a comment


Copy link


Copy Markdown

Contributor
Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Pull request overview
This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.
Changes:
  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.
Comment threadbuild-tools/scripts/DotNet.targets
Outdated

jonathanpeppersand others
added 2 commits
May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival
merged commit 0320b81
into
mainMay 22, 2026

3 checks passed

@simonrozsival
simonrozsival
deleted the

jonathanpeppers/jubilant-robot

branch
May 22, 2026 12:16
@github-actionsgithub-actionsBot
locked and limited conversation to collaborators
Jun 22, 2026
Sign up for freeto subscribe to this conversation on GitHub.
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Copilot code reviewCopilot
Copilot review effort, defaults to Lite
Applies to this pull request for everyone.Learn more about Copilot code review.
Copilot left review comments
@simonrozsivalsimonrozsivalsimonrozsival approved these changes

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Successfully merging this pull request may close these issues.

3 participants

@jonathanpeppers@simonrozsival

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
[build] provision OpenJDK before Java.Interop Prepare - #11442
Merged
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
May 22, 2026
Merged
[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
mainfrom 
jonathanpeppers/jubilant-robot
Conversation
@jonathanpeppers
@jonathanpeppersjonathanpeppers
commented
May 21, 2026

Copy link


Copy Markdown

Member
Context
PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.
Symptom
On a fresh macOS hosted agent (today's main CI build 14159635):
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.
Fix
Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.
The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.
@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 20:04
CopilotAI
reviewed
May 21, 2026
View reviewed changes
CopilotAI
left a comment


Copy link


Copy Markdown

Contributor
Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Pull request overview
This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.
Changes:
  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.
Comment threadbuild-tools/scripts/DotNet.targets
Outdated

jonathanpeppersand others
added 2 commits
May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival
merged commit 0320b81
into
mainMay 22, 2026

3 checks passed

@simonrozsival
simonrozsival
deleted the

jonathanpeppers/jubilant-robot

branch
May 22, 2026 12:16
@github-actionsgithub-actionsBot
locked and limited conversation to collaborators
Jun 22, 2026
Sign up for freeto subscribe to this conversation on GitHub.
Already have an account?
Sign in.


Reviewers

Copilot code reviewCopilot
Copilot review effort, defaults to Lite
Applies to this pull request for everyone.Learn more about Copilot code review.
Copilot left review comments
@simonrozsivalsimonrozsivalsimonrozsival approved these changes

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None yet


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Development

Successfully merging this pull request may close these issues.

3 participants

@jonathanpeppers@simonrozsival

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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[build] provision OpenJDK before Java.Interop Prepare - #11442
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simonrozsival merged 3 commits into
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jonathanpeppers/jubilant-robot
May 22, 2026
Merged
[build] provision OpenJDK before Java.Interop Prepare#11442
simonrozsival merged 3 commits into
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jonathanpeppers/jubilant-robot
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May 21, 2026

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Context
PR #11348 moved the JDK download/install out of xaprepare (which used to run during make prepare) and into the new src/openjdk/openjdk.csprojNoTargets project. That project is only pulled in by src/manifestmerger, src/r8, src/bundletool, and src/java-runtime during make all, so the JDK is no longer present on disk when PrepareJavaInterop runs.
Symptom
On a fresh macOS hosted agent (today's main CI build 14159635):
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory

JdkInfo then silently falls back to scanning system-installed JDKs and writes the highest-version match (Temurin JDK 25, newly preinstalled on the Microsoft-hosted macOS image) into JdkInfo.props as $(JavaSdkDirectory). Later, gradlew is invoked with JAVA_HOME=$(JavaSdkDirectory), so Gradle 8.12 starts its daemon on JDK 25 and crashes:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED

PR #11348's CI did not catch this because it ran on a persistent agent (/Users/builder/...) where /Users/builder/android-toolchain/jdk-21 was already populated from a prior build, so the JdksRoot directory happened to exist and JDK 21 was selected correctly.
Fix
Add a PrepareOpenJDK target in build-tools/scripts/DotNet.targets that builds src/openjdk/openjdk.csproj, and make PrepareJavaInterop depend on it. This ensures the Microsoft OpenJDK is downloaded and extracted into $(JavaSdkDirectory) before Java.Interop's Prepare target scans for a JDK, so we always use the JDK we ship rather than whatever the host image happens to preinstall.
The download/extract is incremental via the existing Inputs/Outputs on _DownloadOpenJDK and _InstallOpenJDK, so the later make all build of Xamarin.Android.sln will not redo the work.
@jonathanpeppers
[build] provision OpenJDK before Java.Interop Prepare
dd008cd
The `PrepareJavaInterop` target invokes Java.Interop's `Prepare`
target with `-p:JdksRoot=$(JavaSdkDirectory)`, but nothing in the
`make prepare` flow has actually downloaded and extracted the
Microsoft OpenJDK into that directory yet. The JDK is only provisioned
later by `src/openjdk/openjdk.csproj` during `make all`.
As a result, Java.Interop's `JdkInfo` task logs:
warning : Could not get information about JdksRoot path
`/Users/runner/android-toolchain/jdk-21`: Not a directory
…and falls back to scanning system-installed JDKs. On the macOS hosted
images this now picks up the preinstalled Temurin JDK 25, which is
written into `JdkInfo.props` as `\$(JavaSdkDirectory)\`. Later in
the build, `gradlew` is invoked with `JAVA_HOME=\$(JavaSdkDirectory)\``
and Gradle 8.12 starts its daemon on JDK 25 — which it does not
support — producing:
FAILURE: Build failed with an exception.
> Could not create task ':test'.
> Could not create an instance of type
org.gradle.api.reporting.internal.DefaultReportContainer.
> Type T not present
BUILD FAILED
Fix this by adding a `PrepareOpenJDK` target that builds
`src/openjdk/openjdk.csproj` before `PrepareJavaInterop` runs, so
the JDK we provision is already present on disk when Java.Interop's
`JdkInfo` task evaluates `JdksRoot`.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
CopilotAI
review requested due to automatic review settings
May 21, 2026 20:04
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May 21, 2026
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Pull request overview
This PR ensures the repository-provisioned Microsoft OpenJDK is present on disk before Java.Interop’s Prepare target runs, preventing hosted agents (notably macOS) from falling back to a preinstalled system JDK (e.g., JDK 25) that can be incompatible with the repo’s Gradle tooling.
Changes:
  • Add a PrepareOpenJDK target that builds src/openjdk/openjdk.csproj to download/install the JDK early.
  • Make PrepareJavaInterop depend on PrepareOpenJDK so JDK selection is deterministic during Java.Interop preparation.
Comment threadbuild-tools/scripts/DotNet.targets
Outdated

jonathanpeppersand others
added 2 commits
May 21, 2026 15:21
@jonathanpeppers
Use <MSBuild/> task instead of <Exec> for openjdk.csproj
d4f8ef5
Avoids backslash-escaping issues when /bin/sh -c invokes the Exec
command on macOS/Linux, and matches how BuildDotNet already invokes
xa-prep-tasks.csproj and Xamarin.Android.sln.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@jonathanpeppers
Restore openjdk.csproj before building it
abb3279
The <MSBuild/> task does not auto-restore, so building openjdk.csproj
without a prior restore fails with NETSDK1004 on agents that have not
yet restored the solution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
@simonrozsival
simonrozsival
merged commit 0320b81
into
mainMay 22, 2026

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