概述
又开始了一个新的系列，这个系列学习Gradle，目标就是彻底理解Gradle,主要还是做下自己理解的笔记，防止忘记
Gradle学习系列（五）：Gradle Transform
Gradle 源码解析
gradlew
首先我们平时打包时用的命令 ./gradlew assembleDebug ，其中的gradlew就是Gradle的入口
exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
这个命令触发了GradleWrapperMain，他还支持$@传递参数，我们平时使用的gradlew命令都是这样运行的
下面看一下GradleWrapperMain
GradleWrapperMain
public class GradleWrapperMain {
//执行gradlew脚本命令触发的入口
public static void main(String[] args) throws Exception {
//这个就是获取工程目录下的wrapper.jar 和 properties 文件
File wrapperJar = wrapperJar();
File propertiesFile = wrapperProperties(wrapperJar);
File rootDir = rootDir(wrapperJar);
...
//下边这俩行是最重要的俩行
WrapperExecutor wrapperExecutor = WrapperExecutor.forWrapperPropertiesFile(propertiesFile);
wrapperExecutor.execute(
args,
new Install(logger,
new Download(logger, "gradlew", wrapperVersion()), new PathAssembler(gradleUserHome)),
new BootstrapMainStarter());
}
WrapperExecutor.forWrapperPropertiesFile就是通过java Properties去解析gradle/wrapper/gradle-wrapper.properties文件,比如distributionUrl
wrapperExecutor.execute其中args就是我们执行gradlew中的参数，Install就是管理本地项目是否有wrapper指定的gradle版本，木有就去解析下载，BootstrapMainStarter就是wrapper执行gradle的真实入口，下面继续看一下execute方法
public void execute(String[] args, Install install, BootstrapMainStarter bootstrapMainStarter) throws Exception {
//config 就是 gradle-wrapper.properties 解析的配置
File gradleHome = install.createDist(config);
bootstrapMainStarter.start(args, gradleHome);
}
install.createDist(config)这个主要做的就是下载gradle wrappe所需要的依赖和源码，其中下载的版本就是gradle/wrapper/gradle-wrapper.properties 里配置的 distributionUrl，下载的地址就是gradle-wrapper.properties 中配置的distributionPath 和 zipStorePath，zipStorePath是下载压缩包的位置，distributionPath就是解压后的位置
Gradle构建包括以下5个流程，这个流程的枚举
private static enum Stage {
LoadSettings,
Configure,
TaskGraph,
RunTasks {
String getDisplayName() {
return "Build";
}
},
Finished;
private Stage() {
}
String getDisplayName() {
return this.name();
}
}
Gradle构建一共经历了5个流程，下面我们依次分析一下这几个流程
一.LoadSettings
loadSettings 主要是加载 settings.gradle 文件，然后创建对应的 project。
bootstrapMainStarter.start作用是开始执行gradle的构建流程，经过复杂的调用过程，最终会触发DefaultGradleLauncher.executeTasks()方法,我们看下这个方法
public GradleInternal executeTasks() {
this.doBuildStages(DefaultGradleLauncher.Stage.RunTasks);
return this.gradle;
}
调用了doBuildStages方法
private void doBuildStages(DefaultGradleLauncher.Stage upTo) {
//首先判断状态不是Finish
Preconditions.checkArgument(upTo != DefaultGradleLauncher.Stage.Finished, "Stage.Finished is not supported by doBuildStages.");
try {
if (upTo == DefaultGradleLauncher.Stage.RunTasks && this.instantExecution.canExecuteInstantaneously()) {
//如果状态是RunTasks，就执行这个方法
this.doInstantExecution();
} else {
//不是RunTasks就执行下面
this.doClassicBuildStages(upTo);
}
} catch (Throwable var3) {
this.finishBuild(upTo.getDisplayName(), var3);
}
}
接下来看下doClassicBuildStages
private void doClassicBuildStages(DefaultGradleLauncher.Stage upTo) {
this.prepareSettings();
if (upTo != DefaultGradleLauncher.Stage.LoadSettings) {
this.prepareProjects();
if (upTo != DefaultGradleLauncher.Stage.Configure) {
this.prepareTaskExecution();
if (upTo != DefaultGradleLauncher.Stage.TaskGraph) {
this.instantExecution.saveScheduledWork();
this.runWork();
}
}
}
}
这段代码，是按照状态划分，分别区分每个状态需要执行的方法
- 当状态是LoadSettings时，执行prepareSettings，主要是加载setting.gralde文件,然后创建对应的project
- 当状态是Configure，执行prepareProjects
- 当状态是TaskGraph，执行prepareTaskExecution
- 当状态是RunTasks，执行instantExecution.saveScheduledWork()和runWork()
下面继续看下prepareSettings方法
private void prepareSettings() {
if (this.stage == null) {
this.buildListener.buildStarted(this.gradle);
this.settingsPreparer.prepareSettings(this.gradle);
//把状态设置为LoadSettings
this.stage = DefaultGradleLauncher.Stage.LoadSettings;
}
}
buildListener.buildStarted(this.gradle)
首先调用buildListener.buildStarted(this.gradle);通知构建开始，在之前的文章说过这个回调
settingsPreparer.prepareSettings(this.gradle);
然后执行到了DefaultSettingsPreparer的prepareSettings方法
public void prepareSettings(GradleInternal gradle) {
//执行init.gradle脚本
this.initScriptHandler.executeScripts(gradle);
SettingsLoader settingsLoader = gradle.getParent() != null ? this.settingsLoaderFactory.forNestedBuild() : this.settingsLoaderFactory.forTopLevelBuild();
//查找并且加载setting.gradle的位置
settingsLoader.findAndLoadSettings(gradle);
}
prepareSettings主要做了俩件事
- 执行init.gradle脚本
- 查找并且加载setting.gradle的位置
而这里的findAndLoadSettings方法做了很多事情，如下：
- 查找setting.gradle的位置
- 编译buildSrc文件夹下的内容，这个就是之前说的buildSrc插件
- 解析 gradle.properites
- 解析setting.gradle
- 创建project及subproject
二.configureBuild
执行完LoadSettings下面就是configureBuild配置阶段，而配置阶段所做的事情就是把gradle脚本编译成class，并执行，这个阶段执行prepareProjects方法
private void prepareProjects() {
if (this.stage == DefaultGradleLauncher.Stage.LoadSettings) {
//准备classlocder
ClassLoaderScope baseProjectClassLoaderScope = this.buildSourceBuilder.buildAndCreateClassLoader(this.gradle);
this.gradle.setBaseProjectClassLoaderScope(baseProjectClassLoaderScope);
//这里调用DefaultProjectsPreparer的prepareProjects方法
this.projectsPreparer.prepareProjects(this.gradle);
//把状态重置为Configure
this.stage = DefaultGradleLauncher.Stage.Configure;
}
}
接下来看下DefaultProjectsPreparer的prepareProjects方法
public void prepareProjects(GradleInternal gradle) {
this.maybeInformAboutIncubatingMode(gradle);
this.buildLoader.load(gradle.getSettings(), gradle);
if (gradle.getParent() == null) {
this.buildRegistry.beforeConfigureRootBuild();
}
// 注释1
if (gradle.getStartParameter().isConfigureOnDemand()) {
this.projectConfigurer.configure(gradle.getRootProject());
} else {
//注释2
this.projectConfigurer.configureHierarchy(gradle.getRootProject());
(new ProjectsEvaluatedNotifier(this.buildOperationExecutor)).notify(gradle);
}
this.modelConfigurationListener.onConfigure(gradle);
}
- 注释1处：如果在 gradle.properties 文件中指定了参数 configure-on-demand，则只会配置主项目以及执行 task 所需要的项目。
- 注释2处：如果没有配置指定参数那么，那么就去配置所有的项目，最后调用的是
TaskPathProjectEvaluator的configureHierarchy方法
public void configureHierarchy(ProjectInternal project) {
this.configure(project);
Iterator var2 = project.getSubprojects().iterator();
while(var2.hasNext()) {
Project sub = (Project)var2.next();
this.configure((ProjectInternal)sub);
}
}
这里遍历所有的porject，然后配置了所有的project，configure方法最后会调用EvaluateProject的run方法
public void run(final BuildOperationContext context) {
this.project.getMutationState().withMutableState(new Runnable() {
public void run() {
try {
EvaluateProject.this.state.toBeforeEvaluate();
//回调ProjectEvaluationListener的beforeEvaluate接口
LifecycleProjectEvaluator.this.buildOperationExecutor.run(new LifecycleProjectEvaluator.NotifyBeforeEvaluate(EvaluateProject.this.project, EvaluateProject.this.state));
if (!EvaluateProject.this.state.hasFailure()) {
EvaluateProject.this.state.toEvaluate();
try {
// 2、在 evaluate 方法中会设置默认的 init、wrapper task 和 默认插件，然后便会编译、执行 build.gradle 脚本
LifecycleProjectEvaluator.this.delegate.evaluate(EvaluateProject.this.project, EvaluateProject.this.state);
} catch (Exception var10) {
LifecycleProjectEvaluator.addConfigurationFailure(EvaluateProject.this.project, EvaluateProject.this.state, var10, context);
} finally {
EvaluateProject.this.state.toAfterEvaluate();
//回调ProjectEvaluationListener的afterEvaluate
LifecycleProjectEvaluator.this.buildOperationExecutor.run(new LifecycleProjectEvaluator.NotifyAfterEvaluate(EvaluateProject.this.project, EvaluateProject.this.state));
}
}
if (EvaluateProject.this.state.hasFailure()) {
EvaluateProject.this.state.rethrowFailure();
} else {
context.setResult(ConfigureProjectBuildOperationType.RESULT);
}
} finally {
EvaluateProject.this.state.configured();
}
}
});
}
这个方法主要做了三件事情
- 回调ProjectEvaluationListener 的 beforeEvaluate 接口
evaluate设置init 和 wrapper俩个默认task，设置默认的帮助插件org.gradle.help-tasks,并且编译并执行build.gradle- 回调 ProjectEvaluationListener.afterEvaluate 接口。
三. TaskGraph
执行完初始化和配置阶段，接下里就是配置task有向图了，这个阶段调用了DefaultGradleLauncher的prepareTaskExecution方法，创建一个有向无环图
private void prepareTaskExecution() {
if (this.stage == DefaultGradleLauncher.Stage.Configure) {
this.taskExecutionPreparer.prepareForTaskExecution(this.gradle);
//更改阶段为TaskGraph
this.stage = DefaultGradleLauncher.Stage.TaskGraph;
}
}
接下来调用了BuildOperatingFiringTaskExecutionPreparer的prepareForTaskExecution
public void prepareForTaskExecution(GradleInternal gradle) {
this.buildOperationExecutor.run(new BuildOperatingFiringTaskExecutionPreparer.CalculateTaskGraph(gradle));
}
然后调用了CalculateTaskGraph的run方法
private class CalculateTaskGraph implements RunnableBuildOperation {
public void run(BuildOperationContext buildOperationContext) {
//填充任务图
final TaskExecutionGraphInternal taskGraph = this.populateTaskGraph();
buildOperationContext.setResult(new Result() {
public List<String> getRequestedTaskPaths() {
return this.toTaskPaths(taskGraph.getRequestedTasks());
}
public List<String> getExcludedTaskPaths() {
return this.toTaskPaths(taskGraph.getFilteredTasks());
}
private List<String> toTaskPaths(Set<Task> tasks) {
return ImmutableSortedSet.copyOf(Collections2.transform(tasks, new Function<Task, String>() {
public String apply(Task task) {
return task.getPath();
}
})).asList();
}
});
}
}
这里直接调用populateTaskGraph方法填充任务图，我们看下这个方法
TaskExecutionGraphInternal populateTaskGraph() {
BuildOperatingFiringTaskExecutionPreparer.this.delegate.prepareForTaskExecution(this.gradle);
return this.gradle.getTaskGraph();
}
这里有调用了DefaultTaskExecutionPreparer的prepareForTaskExecution方法
public void prepareForTaskExecution(GradleInternal gradle) {
//注释1
this.buildConfigurationActionExecuter.select(gradle);
TaskExecutionGraphInternal taskGraph = gradle.getTaskGraph();
//注释2
taskGraph.populate();
this.includedBuildControllers.populateTaskGraphs();
if (gradle.getStartParameter().isConfigureOnDemand()) {
(new ProjectsEvaluatedNotifier(this.buildOperationExecutor)).notify(gradle);
}
}
先看下注释1处，最终调用了DefaultBuildConfigurationActionExecuter的select方法,源码如下
public void select(final GradleInternal gradle) {
this.projectStateRegistry.withLenientState(new Runnable() {
public void run() {
//创建集合
List<BuildConfigurationAction> processingBuildActions = CollectionUtils.flattenCollections(BuildConfigurationAction.class, new Object[]{
DefaultBuildConfigurationActionExecuter.this.configurationActions, DefaultBuildConfigurationActionExecuter.this.taskSelectors});
//然后调用了configure方法
DefaultBuildConfigurationActionExecuter.this.configure(processingBuildActions, gradle, 0);
}
});
}
需要注意的是，首先创建了一个List，然后调用了configure方法，我们看下configure方法的源码
private void configure(final List<BuildConfigurationAction> processingConfigurationActions, final GradleInternal gradle, final int index) {
if (index < processingConfigurationActions.size()) {
((BuildConfigurationAction)processingConfigurationActions.get(index)).configure(new BuildExecutionContext() {
public GradleInternal getGradle() {
return gradle;
}
public void proceed() {
DefaultBuildConfigurationActionExecuter.this.configure(processingConfigurationActions, gradle, index + 1);
}
});
}
}
这里可以看到其实就是依次从List中取出类，然后依次执行ExcludedTaskFilteringBuildConfigurationAction，DefaultTasksBuildExecutionAction
TaskNameResolvingBuildConfigurationAction，执行类的configure方法
下面依次看下这几个类的configure方法
ExcludedTaskFilteringBuildConfigurationAction ## configure
public void configure(BuildExecutionContext context) {
GradleInternal gradle = context.getGradle();
//获取需要排除的task
Set<String> excludedTaskNames = gradle.getStartParameter().getExcludedTaskNames();
if (!excludedTaskNames.isEmpty()) {
Set<Spec<Task>> filters = new HashSet();
Iterator var5 = excludedTaskNames.iterator();
while(var5.hasNext()) {
String taskName = (String)var5.next();
filters.add(this.taskSelector.getFilter(taskName));
}
//给TaskGraph，添加需要过滤的task
gradle.getTaskGraph().useFilter(Specs.intersect(filters));
}
context.proceed();
}
这里主要是给TaskGraph设置了filter去处理需要排除的task，以便后面计算依赖的时候排除相应的task
DefaultTasksBuildExecutionAction ## configure
public void configure(BuildExecutionContext context) {
StartParameter startParameter = context.getGradle().getStartParameter();
Iterator var3 = startParameter.getTaskRequests().iterator();
TaskExecutionRequest request;
do {
if (!var3.hasNext()) {
ProjectInternal project = context.getGradle().getDefaultProject();
this.projectConfigurer.configure(project);
List<String> defaultTasks = project.getDefaultTasks();
if (defaultTasks.size() == 0) {
defaultTasks = Collections.singletonList("help");
LOGGER.info("No tasks specified. Using default task {}", GUtil.toString(defaultTasks));
} else {
LOGGER.info("No tasks specified. Using project default tasks {}", GUtil.toString(defaultTasks));
}
startParameter.setTaskNames(defaultTasks);
context.proceed();
return;
}
request = (TaskExecutionRequest)var3.next();
} while(request.getArgs().isEmpty());
context.proceed();
}
这里会检查命令行会不会传进来Task的名称，如果指定了要执行的Task，那么什么都不做
如果没有指定就看project中是否有默认的Task，默认的task可以通过defaultTasks在build.gradle中指定
如果默认的task也没有，那就把指定Task 设置为 Help Task
TaskNameResolvingBuildConfigurationAction ## configure
public void configure(BuildExecutionContext context) {
GradleInternal gradle = context.getGradle();
TaskExecutionGraphInternal taskGraph = gradle.getTaskGraph();
List<TaskExecutionRequest> taskParameters = gradle.getStartParameter().getTaskRequests();
Iterator var5 = taskParameters.iterator();
while(var5.hasNext()) {
TaskExecutionRequest taskParameter = (TaskExecutionRequest)var5.next();
//解析task
List<TaskSelection> taskSelections = this.commandLineTaskParser.parseTasks(taskParameter);
Iterator var8 = taskSelections.iterator();
//把task添加到taskGraph中
while(var8.hasNext()) {
TaskSelection taskSelection = (TaskSelection)var8.next();
LOGGER.info("Selected primary task '{}' from project {}", taskSelection.getTaskName(), taskSelection.getProjectPath());
taskGraph.addEntryTasks(taskSelection.getTasks());
}
}
context.proceed();
}
这里主要有俩个操作
- 解析Tasks：分析命令行中task 是否指定了Project，如果指定了就拿到改Project中的task，如果没有指定，则会把所有project中的符合task name的全部筛选出来
- 遍历并添加所有已选择的 Tasks 至 taskGraph 实例之中，这里会处理 task 的依赖关系，包括 dependson finalizedby mustrunafter shouldrunafter，然后把信息都保存在 org.gradle.execution.taskgraph.TaskInfo 里
最后回到DefaultTaskExecutionPreparer 的 prepareForTaskExecution 注释2 处
调用taskGraph 的 populate方法，根据上一步的计算的task和依赖关系，生成task图
四.RunTasks
接下来看下RunTasks阶段
private void doClassicBuildStages(DefaultGradleLauncher.Stage upTo) {
this.prepareSettings();
if (upTo != DefaultGradleLauncher.Stage.LoadSettings) {
this.prepareProjects();
if (upTo != DefaultGradleLauncher.Stage.Configure) {
this.prepareTaskExecution();
if (upTo != DefaultGradleLauncher.Stage.TaskGraph) {
this.instantExecution.saveTaskGraph();
// 注释1
this.runWork();
}
}
}
}
RunTasks阶段调用了注释1 处的runWork()方法,我们看下详细代码
private void runWork() {
if (this.stage != DefaultGradleLauncher.Stage.TaskGraph) {
throw new IllegalStateException("Cannot execute tasks: current stage = " + this.stage);
} else {
List<Throwable> taskFailures = new ArrayList();
//注释1
this.buildExecuter.execute(this.gradle, taskFailures);
if (!taskFailures.isEmpty()) {
throw new MultipleBuildFailures(taskFailures);
} else {
this.stage = DefaultGradleLauncher.Stage.RunTasks;
}
}
}
注释1处调用了DefaultBuildWorkExecutor的execute方法
public void execute(GradleInternal gradle, Collection<? super Throwable> failures) {
this.execute(gradle, 0, failures);
}
private void execute(final GradleInternal gradle, final int index, final Collection<? super Throwable> taskFailures) {
if (index < this.executionActions.size()) {
//执行list中类的execute方法
((BuildExecutionAction)this.executionActions.get(index)).execute(new BuildExecutionContext() {
public GradleInternal getGradle() {
return gradle;
}
public void proceed() {
//上一个工执行完成之后，拿到list中下一个执行
DefaultBuildWorkExecutor.this.execute(gradle, index + 1, taskFailures);
}
}, taskFailures);
}
}
这个会首先调用DryRunBuildExecutionAction的execute方法
public void execute(BuildExecutionContext context, Collection<? super Throwable> taskFailures) {
GradleInternal gradle = context.getGradle();
//注释1
if (gradle.getStartParameter().isDryRun()) {
Iterator var4 = gradle.getTaskGraph().getAllTasks().iterator();
while(var4.hasNext()) {
Task task = (Task)var4.next();
this.textOutputFactory.create(DryRunBuildExecutionAction.class).append(((TaskInternal)task).getIdentityPath().getPath()).append(" ").style(Style.ProgressStatus).append("SKIPPED").println();
}
} else {
context.proceed();
}
}
}
在注释1处查看命令行中是否有参数--dry-run,如果有的话就跳过这个task的执行，并输出task名称并且打印出先后关系
然后执行SelectedTaskExecutionAction的execute方法
public void execute(BuildExecutionContext context, Collection<? super Throwable> taskFailures) {
GradleInternal gradle = context.getGradle();
TaskExecutionGraphInternal taskGraph = gradle.getTaskGraph();
if (gradle.getStartParameter().isContinueOnFailure()) {
taskGraph.setContinueOnFailure(true);
}
taskGraph.addTaskExecutionGraphListener(new SelectedTaskExecutionAction.BindAllReferencesOfProjectsToExecuteListener());
//注释1
taskGraph.execute(taskFailures);
}
在注释1处调用了DefaultTaskExecutionGraph的execute方法,我们看下具体代码
public void execute(Collection<? super Throwable> failures) {
ProjectExecutionServiceRegistry projectExecutionServices = new ProjectExecutionServiceRegistry(this.globalServices);
try {
//注释1
this.executeWithServices(projectExecutionServices, failures);
} finally {
projectExecutionServices.close();
}
}
在注释1 处调用了executeWithServices方法,看下源码
private void executeWithServices(ProjectExecutionServiceRegistry projectExecutionServices, Collection<? super Throwable> failures) {
...
try {
//注释1
this.planExecutor.process(this.executionPlan, failures, new DefaultTaskExecutionGraph.BuildOperationAwareExecutionAction(this.buildOperationExecutor.getCurrentOperation(), new DefaultTaskExecutionGraph.InvokeNodeExecutorsAction(this.nodeExecutors, projectExecutionServices)));
LOGGER.debug("Timing: Executing the DAG took " + clock.getElapsed());
} finally {
...
}
}
在注释1处调用了planExecutor.process,最终是调用了DefaultPlanExecutor的process方法
public void process(ExecutionPlan executionPlan, Collection<? super Throwable> failures, Action<Node> nodeExecutor) {
ManagedExecutor executor = this.executorFactory.create("Execution worker for '" + executionPlan.getDisplayName() + "'");
try {
WorkerLease parentWorkerLease = this.workerLeaseService.getCurrentWorkerLease();
//注释1
this.startAdditionalWorkers(executionPlan, nodeExecutor, executor, parentWorkerLease);
(new DefaultPlanExecutor.ExecutorWorker(executionPlan, nodeExecutor, parentWorkerLease, this.cancellationToken, this.coordinationService)).run();
this.awaitCompletion(executionPlan, failures);
} finally {
executor.stop();
}
}
在注释1 处调用了startAdditionalWorkers方法
private void startAdditionalWorkers(ExecutionPlan executionPlan, Action<? super Node> nodeExecutor, Executor executor, WorkerLease parentWorkerLease) {
LOGGER.debug("Using {} parallel executor threads", this.executorCount);
for(int i = 1; i < this.executorCount; ++i) {
executor.execute(new DefaultPlanExecutor.ExecutorWorker(executionPlan, nodeExecutor, parentWorkerLease, this.cancellationToken, this.coordinationService));
}
}
在这里出创建了线程去处理task，默认是8个线程执行task
执行Task前的一些预处理
首先，回调 TaskExecutionListener#beforeExecute。
CatchExceptionTaskExecuter.execute // 加了 try catch，防止执行过程中异常
ExecuteAtMostOnceTaskExecuter.execute // 判断 task 是否执行过
SkipOnlyIfTaskExecuter.execute // 判断 task 的 onlyif 条件是否满足执行
SkipTaskWithNoActionsExecuter.execute // 跳过没有 action 的 task，没有 action 说明 task 不需要执行
ResolveTaskArtifactStateTaskExecuter.execute // 设置 artifact 状态
SkipEmptySourceFilesTaskExecuter.execute // 跳过设置了 source file 但是 source file 为空的 task，source file 为空说明 task 没有需要处理的资源
ValidatingTaskExecuter.execute() // 确认 task 是否可以执行
ResolveTaskOutputCachingStateExecuter.execute // 处理 task output 缓存
SkipUpToDateTaskExecuter.execute // 跳过 update-to-date 的 task
ExecuteActionsTaskExecuter.execute // 真正执行 task
真正执行task
最终调用ExecuteActionsTaskExecuter.TaskExecution的execute来真正执行task
public WorkResult execute(@Nullable InputChangesInternal inputChanges, InputChangesContext context) {
....
WorkResult var5;
try {
var5 = this.executeWithPreviousOutputFiles(inputChanges);
} finally {
outputs.setPreviousOutputFiles((FileCollection)null);
}
return var5;
}
private WorkResult executeWithPreviousOutputFiles(@Nullable InputChangesInternal inputChanges) {
this.task.getState().setExecuting(true);
WorkResult var2;
try {
ExecuteActionsTaskExecuter.LOGGER.debug("Executing actions for {}.", this.task);
//回调 TaskActionListener 的 beforeActions 接口。
ExecuteActionsTaskExecuter.this.actionListener.beforeActions(this.task);
//遍历执行执行所有Action
ExecuteActionsTaskExecuter.this.executeActions(this.task, inputChanges);
var2 = this.task.getState().getDidWork() ? WorkResult.DID_WORK : WorkResult.DID_NO_WORK;
} finally {
this.task.getState().setExecuting(false);
//回调 TaskActionListener 的 beforeActions 接口。
ExecuteActionsTaskExecuter.this.actionListener.afterActions(this.task);
}
return var2;
}
这里主要做了三件事
- 回调 TaskActionListener 的 beforeActions 接口。
- 遍历执行执行所有Action,执行Task的本质就是执行Action
- 回调 TaskActionListener 的 beforeActions 接口。
五.Finish
在 Finished 阶段仅仅只干了一件比较重要的事情，就是 回调 buildListener 的 buildFinished 接口
这里借用【Android 修炼手册】Gradle 篇 – Gradle 源码分析
中的一个流程图，来展示真个流程的顺序
总结
这个gradle构建可以简单总结为一下几个步骤
- 解析seeting.gradle并执行，生成project实例
- 解析build.gradle并执行
- 生成task依赖图
- 执行task
参考
主要参考以下博客，感谢大佬们的付出