settings.gradle: require JDK 17 for the build

.github/workflows/gradle.yml

@@ -9,13 +9,13 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-22.04, macOS-12, windows-2022]
-        java: ['11', '17', '21']
+        java: ['17', '21']
         distribution: ['temurin']
         gradle: ['8.10']
         include:
           # Special case to test something close to Debian config with the oldest supported (standard) Gradle on Ubuntu
           - os: ubuntu-22.04
-            java: '11'
+            java: '17'
             distribution: 'temurin'
             gradle: '4.10.3'
       fail-fast: false

.gitlab-ci.yml

@@ -15,17 +15,6 @@ reference:
     paths:
       - build/**
 
-bullseye-jdk11:
-  image: debian:bullseye-slim
-  before_script:
-    - apt-get update
-    - apt-get -y install openjdk-11-jdk-headless gradle
-  script:
-    - gradle build :bitcoinj-core:publishToMavenLocal :bitcoinj-wallettool:installDist --init-script build-scan-agree.gradle --scan --stacktrace
-  after_script:
-    - gradle --version
-    - sha256sum core/build/libs/*.jar wallettool/build/install/wallet-tool/bin/*  wallettool/build/install/wallet-tool/lib/*.jar
-
 bookworm-jdk17:
   image: debian:bookworm-slim
   before_script:

README.adoc

@@ -22,7 +22,7 @@ To get started, it is best to have the latest JDK and Gradle installed. The HEAD
 
 #### Building from the command line
 
-Official builds are currently using JDK 17. Our GitHub Actions build and test with JDK 11, 17 and 21.
+Official builds are currently using JDK 17. Our GitHub Actions build and test with JDK 17 and 21.
 
 To perform a full build (_including_ JavaDocs, unit/integration _tests_, and `wallettemplate`) use JDK 17+.
 

settings.gradle

@@ -2,6 +2,8 @@ import org.gradle.util.GradleVersion
 
 // Minimum Gradle version for build
 def minGradleVersion = GradleVersion.version("4.4")
+// Minimum Gradle version for checking for minimum Java version
+def minJavaCheckGradleVersion = GradleVersion.version("6.3")
 // Minimum Gradle version for JUnit5
 def minJunit5GradleVersion = GradleVersion.version("4.6")
 // Minimum Gradle version for builds of JavaFX 17 module using JDK 17
@@ -14,9 +16,8 @@ rootProject.name = 'bitcoinj-parent'
 if (GradleVersion.current().compareTo(minGradleVersion) < 0) {
     throw new GradleScriptException("bitcoinj build requires Gradle ${minGradleVersion} or later", null)
 }
-
-if (!JavaVersion.current().isJava11Compatible()) {
-    throw new GradleScriptException("bitcoinj build requires Java 11 or later", null)
+if (GradleVersion.current().compareTo(minJavaCheckGradleVersion) >= 0 && !JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_17)) {
+    throw new GradleScriptException("bitcoinj build requires Java 17 or later", null)
 }
 
 include 'core'
@@ -31,12 +32,12 @@ project(':wallettool').name = 'bitcoinj-wallettool'
 include 'examples'
 project(':examples').name = 'bitcoinj-examples'
 
-if (GradleVersion.current().compareTo(minFxGradleVersion) > 0 && JavaVersion.current().isCompatibleWith(JavaVersion.VERSION_17)) {
+if (GradleVersion.current().compareTo(minFxGradleVersion) > 0) {
     System.err.println "Including wallettemplate because ${GradleVersion.current()}"
     include 'wallettemplate'
     project(':wallettemplate').name = 'bitcoinj-wallettemplate'
 } else {
-    System.err.println "Skipping wallettemplate, requires Gradle ${minFxGradleVersion}+ and Java 17+, currently running Gradle: ${GradleVersion.current()}, Java ${JavaVersion.current()}"
+    System.err.println "Skipping wallettemplate, requires Gradle ${minFxGradleVersion}+, currently running: ${GradleVersion.current()}"
 }
 
 if (GradleVersion.current().compareTo(minJunit5GradleVersion) >= 0) {