DefaultToolchainManager.java
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package org.apache.maven.impl;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.concurrent.ConcurrentHashMap;
import java.util.stream.Stream;
import org.apache.maven.api.Project;
import org.apache.maven.api.Session;
import org.apache.maven.api.SessionData;
import org.apache.maven.api.Toolchain;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.di.Inject;
import org.apache.maven.api.di.Named;
import org.apache.maven.api.di.Singleton;
import org.apache.maven.api.model.Build;
import org.apache.maven.api.model.Plugin;
import org.apache.maven.api.model.Source;
import org.apache.maven.api.services.Lookup;
import org.apache.maven.api.services.ToolchainFactory;
import org.apache.maven.api.services.ToolchainFactoryException;
import org.apache.maven.api.services.ToolchainManager;
import org.apache.maven.api.services.ToolchainManagerException;
import org.apache.maven.api.toolchain.ToolchainModel;
import org.apache.maven.api.xml.XmlNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@Named
@Singleton
public class DefaultToolchainManager implements ToolchainManager {
private final Map<String, ToolchainFactory> factories;
private final Logger logger;
private volatile boolean sourceLevelCheckEmitted;
@Inject
public DefaultToolchainManager(Map<String, ToolchainFactory> factories) {
this(factories, (Logger) null);
}
/**
* Constructor with custom logger. Used by the compatibility layer and tests.
*/
public DefaultToolchainManager(Map<String, ToolchainFactory> factories, Logger logger) {
this.factories = factories;
this.logger = logger != null ? logger : LoggerFactory.getLogger(DefaultToolchainManager.class);
}
@Nonnull
@Override
public List<Toolchain> getToolchains(
@Nonnull Session session, @Nonnull String type, @Nullable Map<String, String> requirements)
throws ToolchainManagerException {
ToolchainFactory factory = factories.get(Objects.requireNonNull(type, "type"));
if (factory == null) {
logger.error("Missing toolchain factory for type: " + type + ". Possibly caused by misconfigured project.");
return List.of();
}
return Stream.concat(
session.getToolchains().stream()
.filter(model -> Objects.equals(type, model.getType()))
.map(this::createToolchain)
.flatMap(Optional::stream),
factory.createDefaultToolchain().stream())
.filter(toolchain -> requirements == null || toolchain.matchesRequirements(requirements))
.toList();
}
@Nonnull
@Override
public Optional<Toolchain> getToolchainFromBuildContext(@Nonnull Session session, @Nonnull String type)
throws ToolchainManagerException {
Map<String, Object> context = retrieveContext(session);
ToolchainModel model = (ToolchainModel) context.get("toolchain-" + type);
if (model != null) {
return createToolchain(model);
}
// For JDK type, check if the running JDK supports the project's source level
// and emit a clear, actionable error if not
if ("jdk".equals(type)) {
checkJdkSourceLevelCompatibility(session);
}
return Optional.empty();
}
@Override
public void storeToolchainToBuildContext(@Nonnull Session session, @Nonnull Toolchain toolchain) {
Map<String, Object> context = retrieveContext(session);
context.put("toolchain-" + toolchain.getType(), toolchain.getModel());
}
/**
* Checks whether the running JDK supports the project's required {@code --source}/{@code --release}
* level. If not, emits a clear, actionable error message instead of letting the build fail later
* with a cryptic javac error.
* <p>
* The error tells the user exactly which JDK version they need and how to fix it
* (run {@code mvnup} to add the {@code maven-toolchains-plugin} with automatic JDK discovery).
*/
void checkJdkSourceLevelCompatibility(Session session) {
// Avoid repeating the error for every module in --fail-at-end mode
if (sourceLevelCheckEmitted) {
return;
}
int requiredSourceLevel = getProjectRequiredSourceLevel(session);
if (requiredSourceLevel <= 0) {
return;
}
int runningJdkMajor = getRunningJdkMajor();
if (JdkSourceLevelSupport.supportsSourceLevel(runningJdkMajor, requiredSourceLevel)) {
return;
}
// Running JDK is incompatible ��� emit clear, actionable error (once per build)
sourceLevelCheckEmitted = true;
int latestJdk = JdkSourceLevelSupport.latestJdkForSourceLevel(requiredSourceLevel);
logger.error(
"Project requires --source {} which needs JDK <= {}, but the running JDK {} no longer supports it.",
requiredSourceLevel,
latestJdk,
runningJdkMajor);
logger.error("To fix: run 'mvnup' to add the maven-toolchains-plugin with automatic JDK discovery,");
logger.error(
"or install JDK {} and configure it in toolchains.xml or via the maven-toolchains-plugin.", latestJdk);
}
/**
* Reads the project's required source level from Model 4.1.0
* {@code <source><targetVersion>} elements, legacy properties
* ({@code maven.compiler.release}, {@code maven.compiler.source}),
* or compiler plugin configuration ({@code <release>}, {@code <source>}).
*
* @return the required source level as a major version, or {@code -1} if none is specified
*/
int getProjectRequiredSourceLevel(Session session) {
Optional<Project> current = session.getService(Lookup.class).lookupOptional(Project.class);
if (current.isEmpty()) {
return -1;
}
Project project = current.get();
// Check Model 4.1.0 <source><targetVersion> elements ��� take the minimum
// across all source directories so the most constraining level wins
Build build = project.getModel().getBuild();
if (build != null) {
List<Source> sources = build.getSources();
if (sources != null) {
int minLevel = Integer.MAX_VALUE;
for (Source source : sources) {
String targetVersion = source.getTargetVersion();
if (targetVersion != null && !targetVersion.isEmpty()) {
int level = JdkSourceLevelSupport.normalizeSourceLevel(targetVersion);
if (level > 0 && level < minLevel) {
minLevel = level;
}
}
}
if (minLevel != Integer.MAX_VALUE) {
return minLevel;
}
}
}
// Fall back to legacy properties
Map<String, String> properties = project.getModel().getProperties();
if (properties != null) {
// maven.compiler.release takes precedence
String release = properties.get("maven.compiler.release");
if (release != null && !release.isEmpty()) {
int level = JdkSourceLevelSupport.normalizeSourceLevel(release);
if (level > 0) {
return level;
}
}
// Then maven.compiler.source
String source = properties.get("maven.compiler.source");
if (source != null && !source.isEmpty()) {
int level = JdkSourceLevelSupport.normalizeSourceLevel(source);
if (level > 0) {
return level;
}
}
}
// Fall back to compiler plugin configuration (<release>, <source>)
int pluginLevel = getSourceLevelFromCompilerPlugin(build);
if (pluginLevel > 0) {
return pluginLevel;
}
return -1;
}
/**
* Reads the source level from the maven-compiler-plugin configuration.
* Checks both {@code <release>} and {@code <source>} elements in the plugin's
* {@code <configuration>} block.
*
* @return the source level, or {@code -1} if not configured
*/
private int getSourceLevelFromCompilerPlugin(Build build) {
if (build == null) {
return -1;
}
for (Plugin plugin : build.getPlugins()) {
if ("maven-compiler-plugin".equals(plugin.getArtifactId())
&& (plugin.getGroupId() == null
|| plugin.getGroupId().isEmpty()
|| "org.apache.maven.plugins".equals(plugin.getGroupId()))) {
XmlNode config = plugin.getConfiguration();
if (config != null) {
// <release> takes precedence over <source>
XmlNode releaseNode = config.child("release");
if (releaseNode != null
&& releaseNode.value() != null
&& !releaseNode.value().isBlank()) {
int level = JdkSourceLevelSupport.normalizeSourceLevel(
releaseNode.value().trim());
if (level > 0) {
return level;
}
}
XmlNode sourceNode = config.child("source");
if (sourceNode != null
&& sourceNode.value() != null
&& !sourceNode.value().isBlank()) {
int level = JdkSourceLevelSupport.normalizeSourceLevel(
sourceNode.value().trim());
if (level > 0) {
return level;
}
}
}
}
}
return -1;
}
/**
* Returns the major version of the running JDK.
* Extracted as a method so tests can override it.
*/
int getRunningJdkMajor() {
return JdkSourceLevelSupport.getRunningJdkMajor();
}
private Optional<Toolchain> createToolchain(ToolchainModel model) {
String type = Objects.requireNonNull(model.getType(), "model.getType()");
ToolchainFactory factory = factories.get(type);
if (factory != null) {
try {
return Optional.of(factory.createToolchain(model));
} catch (ToolchainFactoryException e) {
throw new ToolchainManagerException("Error creating toolchain of type " + type, e);
}
} else {
logger.error("Missing toolchain factory for type: " + type + ". Possibly caused by misconfigured project.");
}
return Optional.empty();
}
private static final SessionData.Key<ConcurrentHashMap<Project, ConcurrentHashMap<String, Object>>>
TOOLCHAIN_CONTEXT_KEY = (SessionData.Key) SessionData.key(ConcurrentHashMap.class, "toolchain-context");
protected Map<String, Object> retrieveContext(Session session) {
Optional<Project> current = session.getService(Lookup.class).lookupOptional(Project.class);
if (current.isPresent()) {
var map = session.getData().computeIfAbsent(TOOLCHAIN_CONTEXT_KEY, ConcurrentHashMap::new);
return map.computeIfAbsent(current.get(), p -> new ConcurrentHashMap<>());
}
return new HashMap<>();
}
}