Move classloader-related logic to new :classloaders subproject (gradl…

…e#32430)

.teamcity/subprojects.json

@@ -188,6 +188,13 @@
     "functionalTests": false,
     "crossVersionTests": false
   },
+  {
+    "name": "classloaders",
+    "path": "platforms/core-runtime/classloaders",
+    "unitTests": false,
+    "functionalTests": false,
+    "crossVersionTests": false
+  },
   {
     "name": "cli",
     "path": "platforms/core-runtime/cli",

platforms/core-configuration/configuration-cache/build.gradle.kts

@@ -39,6 +39,7 @@ dependencies {
     // TODO - it might be good to allow projects to contribute state to save and restore, rather than have this project know about everything
     implementation(projects.buildEvents)
     implementation(projects.buildOption)
+    implementation(projects.classloaders)
     implementation(projects.coreKotlinExtensions)
     implementation(projects.coreSerializationCodecs)
     implementation(projects.dependencyManagementSerializationCodecs)

platforms/core-configuration/kotlin-dsl-provider-plugins/build.gradle.kts

@@ -5,7 +5,7 @@ plugins {
 description = "Kotlin DSL Provider Plugins"
 
 dependencies {
-    api(projects.baseServices)
+    api(projects.classloaders)
     api(projects.core)
     api(projects.coreApi)
     api(projects.kotlinDsl)
@@ -18,6 +18,7 @@ dependencies {
     api(libs.inject)
     api(libs.kotlinStdlib)
 
+    implementation(projects.baseServices)
     implementation(projects.concurrent)
     implementation(projects.functional)
     implementation(projects.fileCollections)

platforms/core-configuration/kotlin-dsl-tooling-builders/build.gradle.kts

@@ -9,6 +9,7 @@ dependencies {
     api(projects.core)
     api(libs.kotlinStdlib)
 
+    implementation(projects.classloaders)
     implementation(projects.serviceLookup)
     implementation(projects.stdlibJavaExtensions)
     implementation(projects.time)

platforms/core-configuration/kotlin-dsl/build.gradle.kts

@@ -10,6 +10,7 @@ description = "Kotlin DSL Provider"
 dependencies {
     api(projects.buildProcessServices)
     api(projects.baseServices)
+    api(projects.classloaders)
     api(projects.core)
     api(projects.coreApi)
     api(projects.concurrent)

platforms/core-configuration/model-core/build.gradle.kts

@@ -30,6 +30,7 @@ dependencies {
 
     implementation(projects.baseServicesGroovy)
     implementation(projects.baseAsm)
+    implementation(projects.classloaders)
     implementation(projects.logging)
     implementation(projects.problemsApi)
     implementation(projects.serviceProvider)

platforms/core-execution/worker-main/build.gradle.kts

@@ -20,6 +20,7 @@ dependencies {
     api(projects.native)
     api(libs.jsr305)
 
+    implementation(projects.classloaders)
     implementation(projects.concurrent)
     implementation(projects.enterpriseLogging)
     implementation(projects.serviceProvider)

platforms/core-execution/workers/build.gradle.kts

@@ -7,6 +7,7 @@ description = "Infrastructure for starting and managing worker processes"
 dependencies {
     api(projects.baseServices)
     api(projects.buildOperations)
+    api(projects.classloaders)
     api(projects.concurrent)
     api(projects.core)
     api(projects.coreApi)

platforms/core-runtime/base-services/build.gradle.kts

@@ -30,17 +30,17 @@ tasks.named<JavaCompile>("jmhCompileGeneratedClasses") {
 moduleIdentity.createBuildReceipt()
 
 dependencies {
+    api(projects.buildOperations)
+    api(projects.classloaders)
     api(projects.concurrent)
-    api(projects.stdlibJavaExtensions)
     api(projects.fileTemp)
-    api(projects.serviceLookup)
     api(projects.hashing)
-    api(projects.buildOperations)
+    api(projects.serviceLookup)
+    api(projects.stdlibJavaExtensions)
     api(libs.inject)
     api(libs.jsr305)
     api(libs.guava)
 
-    implementation(projects.io)
     implementation(projects.time)
     implementation(projects.baseAsm)
 

platforms/core-runtime/base-services/src/test/groovy/org/gradle/internal/classloader/FilteringClassLoaderTest.groovy

@@ -15,6 +15,7 @@
  */
 package org.gradle.internal.classloader
 
+
 import org.gradle.test.precondition.Requires
 import org.gradle.test.preconditions.UnitTestPreconditions
 import org.junit.Before
@@ -344,7 +345,7 @@ class FilteringClassLoaderTest extends Specification {
     void "spec is copied correctly"() {
         given:
         def parent = Mock(ClassLoader, useObjenesis: false)
-        def spec = new FilteringClassLoader.Spec([ 'allow.ClassName' ], [ 'allowPackage' ], [ 'allowPackagePrefix' ], [ 'allowPackageResource' ], [ 'allowResource' ], [ 'disallow.ClassName' ], [ 'disallowPackage' ])
+        def spec = new FilteringClassLoader.Spec(['allow.ClassName' ], ['allowPackage' ], ['allowPackagePrefix' ], ['allowPackageResource' ], ['allowResource' ], ['disallow.ClassName' ], ['disallowPackage' ])
         def filteringClassLoader = new FilteringClassLoader(parent, spec)
         def visitor = Mock(ClassLoaderVisitor)
 

platforms/core-runtime/build-process-services/build.gradle.kts

@@ -5,10 +5,12 @@ plugins {
 description = "Services and types used to setup a build process from a Gradle distribution."
 
 dependencies {
+    api(projects.classloaders)
     api(projects.stdlibJavaExtensions)
-    api(projects.baseServices)
     api(libs.jsr305)
 
+    implementation(projects.baseServices)
+
     implementation(libs.guava)
 
     testImplementation(libs.asm)

platforms/core-runtime/build-process-services/src/main/java/org/gradle/api/internal/DefaultClassPathProvider.java

@@ -52,6 +52,7 @@ public ClassPath findClassPath(String name) {
         if (name.equals("DEPENDENCIES-EXTENSION-COMPILER")) {
             ClassPath classpath = ClassPath.EMPTY;
             classpath = classpath.plus(moduleRegistry.getModule("gradle-base-services").getImplementationClasspath());
+            classpath = classpath.plus(moduleRegistry.getModule("gradle-classloaders").getImplementationClasspath());
             classpath = classpath.plus(moduleRegistry.getModule("gradle-core-api").getImplementationClasspath());
             classpath = classpath.plus(moduleRegistry.getModule("gradle-core").getImplementationClasspath());
             classpath = classpath.plus(moduleRegistry.getModule("gradle-stdlib-java-extensions").getImplementationClasspath());

platforms/core-runtime/build-state/build.gradle.kts

@@ -22,6 +22,7 @@ description = "Types for build process and session state management"
 
 dependencies {
     api(projects.baseServices)
+    api(projects.classloaders)
     api(projects.core)
     api(projects.daemonProtocol)
     api(projects.instrumentationAgentServices)

platforms/core-runtime/classloaders/build.gradle.kts

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+plugins {
+    id("gradlebuild.distribution.implementation-java")
+}
+
+description = "Tools to handle classloaders"
+
+gradlebuildJava.usedInWorkers()
+
+dependencies {
+    api(projects.hashing)
+    api(projects.stdlibJavaExtensions)
+
+    api(libs.jsr305)
+
+    implementation(projects.baseAsm)
+    implementation(projects.concurrent)
+    implementation(projects.io)
+
+    implementation(libs.commonsIo)
+    implementation(libs.commonsLang)
+    implementation(libs.guava)
+
+    compileOnly(libs.errorProneAnnotations)
+}

platforms/core-runtime/base-services/src/main/java/org/gradle/internal/classloader/CachingClassLoader.java → platforms/core-runtime/classloaders/src/main/java/org/gradle/internal/classloader/CachingClassLoader.java

@@ -32,6 +32,7 @@ public class CachingClassLoader extends ClassLoader implements DelegatingClassLo
 
     static {
         try {
+            //noinspection Since15
             ClassLoader.registerAsParallelCapable();
         } catch (NoSuchMethodError ignore) {
             // Not supported on Java 6

platforms/core-runtime/base-services/src/main/java/org/gradle/internal/classloader/FilteringClassLoader.java → platforms/core-runtime/classloaders/src/main/java/org/gradle/internal/classloader/FilteringClassLoader.java

@@ -16,13 +16,12 @@
 
 package org.gradle.internal.classloader;
 
-import org.gradle.internal.util.Trie;
-
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.io.IOException;
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Enumeration;
 import java.util.HashSet;
@@ -52,6 +51,7 @@ public class FilteringClassLoader extends ClassLoader implements ClassLoaderHier
             SYSTEM_PACKAGES.add(p.getName());
         }
         try {
+            //noinspection Since15
             ClassLoader.registerAsParallelCapable();
         } catch (NoSuchMethodError ignore) {
             // Not supported on Java 6
@@ -181,7 +181,7 @@ private boolean classAllowed(String className) {
             || (packagePrefixes.contains(DEFAULT_PACKAGE + ".") && isInDefaultPackage(className));
     }
 
-    private boolean isInDefaultPackage(String className) {
+    private static boolean isInDefaultPackage(String className) {
         return !className.contains(".");
     }
 
@@ -233,12 +233,12 @@ private static void addAll(Collection<String> collection, Iterable<String> eleme
          */
         public boolean isEmpty() {
             return classNames.isEmpty()
-                    && packageNames.isEmpty()
-                    && packagePrefixes.isEmpty()
-                    && resourcePrefixes.isEmpty()
-                    && resourceNames.isEmpty()
-                    && disallowedClassNames.isEmpty()
-                    && disallowedPackagePrefixes.isEmpty();
+                && packageNames.isEmpty()
+                && packagePrefixes.isEmpty()
+                && resourcePrefixes.isEmpty()
+                && resourceNames.isEmpty()
+                && disallowedClassNames.isEmpty()
+                && disallowedPackagePrefixes.isEmpty();
         }
 
         /**
@@ -355,7 +355,7 @@ public Set<String> getDisallowedPackagePrefixes() {
         }
     }
 
-    private static class TrieSet implements Iterable<String> {
+    public static class TrieSet implements Iterable<String> {
         private final Trie trie;
         private final Set<String> set;
 
@@ -378,4 +378,130 @@ public Iterator<String> iterator() {
             return set.iterator();
         }
     }
+
+    /**
+     * Move the Trie class in :base-services to :functional once we can use Java 8 and delete this class.
+     */
+    public static class Trie implements Comparable<Trie> {
+        private final char chr;
+        private final boolean terminal;
+        private final Trie[] transitions;
+
+        public static Trie from(Iterable<String> words) {
+            Builder builder = new Builder();
+            for (String word : words) {
+                builder.addWord(word);
+            }
+            return builder.build();
+        }
+
+        private Trie(char chr, boolean terminal, Trie[] transitions) {
+            this.chr = chr;
+            this.terminal = terminal;
+            this.transitions = transitions;
+        }
+
+        @Override
+        public String toString() {
+            StringBuilder sb = new StringBuilder();
+            sb.append(chr).append(terminal ? "(terminal)\n" : "\n");
+            sb.append("Next: ");
+            for (Trie transition : transitions) {
+                sb.append(transition.chr).append(" ");
+            }
+            sb.append("\n");
+            return sb.toString();
+        }
+
+        @Override
+        public int compareTo(@Nonnull Trie o) {
+            return chr - o.chr;
+        }
+
+        /**
+         * Checks if the trie contains the given character sequence or any prefixes of the sequence.
+         */
+        public boolean find(CharSequence seq) {
+            if (seq.length() == 0) {
+                return false;
+            }
+            int idx = 0;
+            Trie cur = this;
+            while (idx < seq.length()) {
+                char c = seq.charAt(idx);
+                boolean found = false;
+                for (Trie transition : cur.transitions) {
+                    if (transition.chr == c) {
+                        cur = transition;
+                        idx++;
+                        found = true;
+                        if (idx == seq.length()) {
+                            return cur.terminal;
+                        }
+                        break;
+                    } else if (transition.chr > c) {
+                        return false;
+                    }
+                }
+                if (!found) {
+                    return cur.terminal;
+                }
+            }
+            return cur.terminal;
+        }
+
+        public static class Builder {
+            private final char chr;
+            private final List<Builder> transitions = new ArrayList<Builder>();
+
+            private boolean terminal;
+
+            public Builder() {
+                chr = '\0';
+            }
+
+            private Builder(char chr) {
+                this.chr = chr;
+            }
+
+            private Builder addTransition(char c, boolean terminal) {
+                Builder b = null;
+                for (Builder transition : transitions) {
+                    if (transition.chr == c) {
+                        b = transition;
+                        break;
+                    }
+                }
+                if (b == null) {
+                    b = new Builder(c);
+                    transitions.add(b);
+                }
+                b.terminal |= terminal;
+                return b;
+            }
+
+            public void addWord(String word) {
+                Trie.Builder cur = this;
+                char[] chars = word.toCharArray();
+                for (int i = 0; i < chars.length; i++) {
+                    char c = chars[i];
+                    cur = cur.addTransition(c, i == chars.length - 1);
+                }
+            }
+
+            public Trie build() {
+                Trie[] transitions = new Trie[this.transitions.size()];
+                for (int i = 0; i < this.transitions.size(); i++) {
+                    Builder transition = this.transitions.get(i);
+                    transitions[i] = transition.build();
+                }
+                Arrays.sort(transitions);
+                return new Trie(chr, terminal, transitions);
+            }
+        }
+    }
+
+    public interface Action<T> {
+        void execute(T target);
+    }
 }