Restored #9435 since even with latest logback Java 21+ tests with virtual threads have a chance to hang on CI. (#10622)

Restored #9435 since even with latest logback Java 21+ tests with virtual threads have a chance to hang on CI.

Co-authored-by: alexey.kuznetsov <alexey.kuznetsov@datadoghq.com>

Author: AlexeyKuznetsov-DD

dd-java-agent/instrumentation/java/java-concurrent/java-concurrent-21.0/build.gradle

@@ -1,5 +1,10 @@
+plugins {
+  id 'idea'
+}
+
 apply from: "$rootDir/gradle/java.gradle"
-apply plugin: 'idea'
+// Use slf4j-simple as default; logback has a high chance of getting stuck in a deadlock on CI.
+apply from: "$rootDir/gradle/slf4j-simple.gradle"
 
 testJvmConstraints {
   minJavaVersion = JavaVersion.VERSION_21
@@ -48,8 +53,5 @@ tasks.named("check") {
 }
 
 dependencies {
-  // Use latest logback for Java 21+ tests with better virtual thread support.
-  testImplementation(libs.logback.classic.latest)
-
   testImplementation project(':dd-java-agent:instrumentation:datadog:tracing:trace-annotation')
 }

dd-java-agent/instrumentation/java/java-concurrent/java-concurrent-25.0/build.gradle

@@ -3,6 +3,8 @@ plugins {
 }
 
 apply from: "$rootDir/gradle/java.gradle"
+// Use slf4j-simple as default; logback has a high chance of getting stuck in a deadlock on CI.
+apply from: "$rootDir/gradle/slf4j-simple.gradle"
 
 muzzle {
   pass {
@@ -15,8 +17,3 @@ idea {
     jdkName = '25'
   }
 }
-
-dependencies {
-  // Use latest logback for Java 21+ tests with better virtual thread support.
-  testImplementation(libs.logback.classic.latest)
-}

dd-java-agent/instrumentation/java/java-lang/java-lang-21.0/build.gradle

@@ -3,6 +3,8 @@ plugins {
 }
 
 apply from: "$rootDir/gradle/java.gradle"
+// Use slf4j-simple as default; logback has a high chance of getting stuck in a deadlock on CI.
+apply from: "$rootDir/gradle/slf4j-simple.gradle"
 
 testJvmConstraints {
   minJavaVersion = JavaVersion.VERSION_21
@@ -26,8 +28,5 @@ tasks.named("compileTestJava", JavaCompile) {
 }
 
 dependencies {
-  // Use latest logback for Java 21+ tests with better virtual thread support.
-  testImplementation(libs.logback.classic.latest)
-
   testImplementation project(':dd-java-agent:instrumentation:datadog:tracing:trace-annotation')
 }

gradle/libs.versions.toml

@@ -57,7 +57,6 @@ lz4 = "1.7.1"
 # Logging
 slf4j = "1.7.30"
 logback = "1.2.13" # required by Java 8 modules.
-logback-latest = "1.5.28" # recommended for Java 11+ modules.
 
 # JSON
 jackson = "2.20.0"
@@ -135,7 +134,6 @@ lz4 = { module = "org.lz4:lz4-java", version.ref = "lz4" }
 
 # Logging
 logback-classic = { module = "ch.qos.logback:logback-classic", version.ref = "logback" }
-logback-classic-latest = { module = "ch.qos.logback:logback-classic", version.ref = "logback-latest" }
 logback-core = { module = "ch.qos.logback:logback-core", version.ref = "logback" }
 log4j-over-slf4j = { module = "org.slf4j:log4j-over-slf4j", version.ref = "slf4j" }
 jcl-over-slf4j = { module = "org.slf4j:jcl-over-slf4j", version.ref = "slf4j" }

gradle/slf4j-simple.gradle

@@ -0,0 +1,27 @@
+// Apply this script when `slf4j-simple` should be used instead of `logback`.
+
+configurations.configureEach { cfg ->
+  def name = cfg.name
+
+  if (name.containsIgnoreCase("test")) {
+    // Exclude Logback from all test-like runtimeClasspath configurations.
+    if (name.endsWithIgnoreCase("runtimeClasspath")) {
+      cfg.exclude group: "ch.qos.logback"
+    }
+
+    // Add slf4j-simple to all test-like runtimeOnly configurations.
+    if (name.endsWithIgnoreCase("runtimeOnly")) {
+      project.dependencies.add(name, "org.slf4j:slf4j-simple:${libs.versions.slf4j.get()}")
+    }
+  }
+}
+
+// Configure `slf4j-simple` logger.
+tasks.withType(Test).configureEach {
+  jvmArgs += [
+    "-Dorg.slf4j.simpleLogger.defaultLogLevel=debug",
+    "-Dorg.slf4j.simpleLogger.showThreadName=true",
+    "-Dorg.slf4j.simpleLogger.showDateTime=true",
+    "-Dorg.slf4j.simpleLogger.dateTimeFormat=HH:mm:ss.SSS"
+  ]
+}