Revert addition of logstash.jdk.force setting

.buildkite/scripts/jdk-matrix-tests/generate-steps.py

@@ -190,8 +190,6 @@ def all_jobs(self) -> list[typing.Callable[[], JobRetValues]]:
 
     def prepare_shell(self) -> str:
         jdk_dir = f"/opt/buildkite-agent/.java/{self.jdk}"
-        # JDK 17 is below the supported minimum (21); force Logstash to boot so we can still test it
-        force_opts = '\nexport LS_JAVA_OPTS="-Dlogstash.jdk.force=true ${LS_JAVA_OPTS:-}"' if self.jdk.endswith("_17") else ""
         return f"""#!/usr/bin/env bash
 set -euo pipefail
 
@@ -201,7 +199,7 @@ def prepare_shell(self) -> str:
 # LS env vars for JDK matrix tests
 export BUILD_JAVA_HOME={jdk_dir}
 export RUNTIME_JAVA_HOME={jdk_dir}
-export LS_JAVA_HOME={jdk_dir}{force_opts}
+export LS_JAVA_HOME={jdk_dir}
 
 export PATH="/opt/buildkite-agent/.rbenv/bin:/opt/buildkite-agent/.pyenv/bin:$PATH"
 eval "$(rbenv init -)"

.buildkite/scripts/jdk-matrix-tests/launch-command.ps1

@@ -28,11 +28,6 @@ $env:BUILD_JAVA_HOME = $JAVA_CUSTOM_DIR
 $env:RUNTIME_JAVA_HOME = $JAVA_CUSTOM_DIR
 $env:LS_JAVA_HOME = $JAVA_CUSTOM_DIR
 
-# JDK 17 is below the supported minimum (21); force Logstash to boot so we can still test it
-if ($JDK -like "*_17") {
-    $env:LS_JAVA_OPTS = "-Dlogstash.jdk.force=true $($env:LS_JAVA_OPTS)"
-}
-
 Write-Host "--- Running test: $CIScript"
 try {
     Invoke-Expression $CIScript

build.gradle

@@ -98,11 +98,6 @@ allprojects {
       "--add-opens=java.base/java.lang=ALL-UNNAMED",
       "--add-opens=java.base/java.util=ALL-UNNAMED"
     ]
-    // On JDK < 21 (below LogStash's supported minimum) let in-process specs that boot
-    // LogStash::Runner start instead of aborting (see runner.rb JDK check).
-    if (JavaVersion.current() < JavaVersion.VERSION_21) {
-      jvmArgs += "-Dlogstash.jdk.force=true"
-    }
     maxHeapSize = "2g"
     //https://stackoverflow.com/questions/3963708/gradle-how-to-display-test-results-in-the-console-in-real-time
     testLogging {

config/jvm.options

@@ -87,9 +87,4 @@
 #
 # Sets the maximum nesting depth. The depth is a count of objects and arrays that have not
 # been closed, `{` and `[` respectively.
-#-Dlogstash.jackson.stream-read-constraints.max-nesting-depth=1000
-
-# Bypass JDK version check
-#
-# Setting this to true permit to run Logstash with an unsupported JDK version.
-#-Dlogstash.jdk.force=true
+#-Dlogstash.jackson.stream-read-constraints.max-nesting-depth=1000

logstash-core/lib/logstash/runner.rb

@@ -331,24 +331,15 @@ def execute
       deprecation_logger.deprecated msg
     end
 
-    jvmArgs = ManagementFactory.getRuntimeMXBean().getInputArguments()
     if JavaVersion::CURRENT < JavaVersion::JAVA_11
       logger.warn I18n.t("logstash.runner.java.version",
                                              :java_home => java.lang.System.getProperty("java.home"))
     elsif JavaVersion::CURRENT < JavaVersion::JAVA_17
       deprecation_logger.deprecated I18n.t("logstash.runner.java.version_17_minimum",
                                            :java_home => java.lang.System.getProperty("java.home"))
     elsif JavaVersion::CURRENT < JavaVersion::JAVA_21
-      if force_jdk_check(jvmArgs)
-        logger.warn I18n.t("logstash.runner.java.version_below_21_force",
-                           :java_home => java.lang.System.getProperty("java.home"),
-                           :java_version => JavaVersion::CURRENT)
-      else
-        logger.error I18n.t("logstash.runner.java.version_21_minimum",
-                            :java_home => java.lang.System.getProperty("java.home"), 
-                            :java_version => JavaVersion::CURRENT)
-        return 1
-      end
+      deprecation_logger.deprecated I18n.t("logstash.runner.java.version_21_minimum",
+                                           :java_home => java.lang.System.getProperty("java.home"))
     end
 
     logger.warn I18n.t("logstash.runner.java.home") if ENV["JAVA_HOME"]
@@ -359,6 +350,7 @@ def execute
     end
 
     logger.info("Starting Logstash", "logstash.version" => LOGSTASH_VERSION, "jruby.version" => RUBY_DESCRIPTION)
+    jvmArgs = ManagementFactory.getRuntimeMXBean().getInputArguments()
     logger.info "JVM bootstrap flags: #{jvmArgs}"
 
     # Add local modules to the registry before everything else
@@ -658,8 +650,4 @@ def configure_pipeline_buffer_type
     end
   end
 
-  def force_jdk_check(jvm_args_list)
-    jvm_args_list.include? "-Dlogstash.jdk.force=true"
-  end
-  private :force_jdk_check
 end

logstash-core/locales/en.yml

@@ -453,15 +453,8 @@ en:
           The bundled JDK has been verified to work with each specific version of Logstash, and generally provides best performance and reliability.
           If you have compelling reasons for using your own JDK (organizational-specific compliance requirements, for example), the version you supply with LS_JAVA_HOME must meet the minimum requirements.
         version_21_minimum: >-
-          Starting from Logstash 8.19.19 the minimum required version of Java is 21;
-          your Java version from `%{java_home}` is `%{java_version}` and does not meet this requirement.
-          Running Logstash with the bundled JDK is recommended.
-          The bundled JDK has been verified to work with each specific version of Logstash, and generally provides best performance and reliability.
-          If you have compelling reasons for using your own JDK (organizational-specific compliance requirements, for example), the version you supply with LS_JAVA_HOME must meet the minimum requirements.
-        version_below_21_force: >-
-          Starting from Logstash 8.19.19 the minimum required version of Java is 21;
-          your Java version from `%{java_home}` is `%{java_version}` and does not meet this requirement.
-          You have selected to force the execution with unsupported Java version, and could generate unexpected malfunctions.
+          Java 17 is deprecated and in a future release the minimum required version of Java will be Java 21;
+          your Java version from `%{java_home}` does not meet this requirement.
           Running Logstash with the bundled JDK is recommended.
           The bundled JDK has been verified to work with each specific version of Logstash, and generally provides best performance and reliability.
           If you have compelling reasons for using your own JDK (organizational-specific compliance requirements, for example), the version you supply with LS_JAVA_HOME must meet the minimum requirements.

logstash-core/spec/logstash/runner_spec.rb

@@ -29,7 +29,6 @@
 require "webmock/rspec"
 require_relative "../support/helpers"
 require_relative "../support/matchers"
-java_import 'org.logstash.util.JavaVersion'
 
 describe LogStash::Runner do
   subject(:runner) { LogStash::Runner }
@@ -711,36 +710,6 @@
     end
   end
 
-  describe "JDK 17 compatibility" do
-    subject { LogStash::Runner.new("") }
-    let(:args) { ["-e", "input {} output {}"] }
-    let(:deprecation_logger_stub) { double("DeprecationLogger").as_null_object }
-
-    before(:each) do
-      skip "Test requires JDK 17, found #{JavaVersion::CURRENT}" unless JavaVersion::CURRENT.compare_to(JavaVersion::JAVA_17) == 0
-      allow(runner).to receive(:deprecation_logger).and_return(deprecation_logger_stub)
-      allow(logger).to receive(:error)
-      allow(subject).to receive(:force_jdk_check).and_return(mock_force_jdk_check)
-    end
-
-    context "without -Dlogstash.jdk.force=true" do
-      let(:mock_force_jdk_check) { false }
-      it "logs an error about minimum required Java version 21 and returns exit code 1" do
-        expect(logger).to receive(:error).with(a_string_including("minimum required version of Java is 21"))
-        expect(subject.run(args)).to eq(1)
-      end
-    end
-
-    context "with -Dlogstash.jdk.force=true" do
-      let(:mock_force_jdk_check) { true }
-
-      it "logs a warning about forced execution with unsupported Java version" do
-        expect(logger).to receive(:warn).with(a_string_including("force the execution with unsupported Java version"))
-        subject.run(args)
-      end
-    end
-  end
-
   describe "allow_superuser" do
     subject { LogStash::Runner.new("") }
     let(:args) { ["-e", "input {} output {}"] }

logstash-core/src/main/java/org/logstash/util/JavaVersion.java

@@ -22,7 +22,6 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
-import java.util.stream.Collectors;
 
 /**
  * Helper class to compare current version of JVM with a target version.
@@ -85,9 +84,4 @@ private static int compare(final JavaVersion leftVersion, final JavaVersion righ
     public int compareTo(JavaVersion other) {
         return compare(this, other);
     }
-
-    @Override
-    public String toString() {
-        return version.stream().map(Object::toString).collect(Collectors.joining("."));
-    }
 }