What phases does Gradle's lifecycle include? What is the purpose of each phase?

Gradle's lifecycle consists of three main phases:

1. Initialization Phase

• Purpose: Determine which projects will participate in the build and create Project instances for each
• Execution:
  • Read settings.gradle or settings.gradle.kts file
  • Determine project structure based on include statements
  • Create Project instances for each included project
  • Execute init.gradle (if present)
• Example:

  groovy
  // settings.gradle
  rootProject.name = 'my-project'
  include 'app', 'library', 'common'

2. Configuration Phase

• Purpose: Execute build scripts for all projects and build the task dependency graph
• Execution:
  • Execute build.gradle or build.gradle.kts for each project
  • Configure project properties, plugins, dependencies
  • Create and configure all tasks
  • Establish dependencies between tasks
• Characteristics:
  • All projects are configured even if only one task is executed
  • Use gradle -m or --dry-run to view tasks that will be executed
• Optimization Tips:

  groovy
  // Use onlyIf or enabled to skip unnecessary configuration
  tasks.register('myTask') {
      onlyIf { project.hasProperty('enableMyTask') }
  }

3. Execution Phase

• Purpose: Execute actual tasks according to the task dependency graph
• Execution:
  • Only execute tasks specified on the command line and their dependencies
  • Execute task action logic
  • Support incremental builds, only process changed files
• Characteristics:
  • Task execution order is determined by dependencies
  • Support parallel execution (via --parallel parameter)
  • Support continuous builds (via --continuous parameter)

Lifecycle Hooks

Gradle provides multiple lifecycle hooks to execute custom logic at specific stages:

groovy
// Initialization phase
gradle.projectsLoaded {
    println "All projects loaded"
}

// Configuration phase
gradle.beforeProject { project ->
    println "Configuring project: ${project.name}"
}

gradle.afterProject { project ->
    println "Project ${project.name} configuration complete"
}

// Execution phase
gradle.taskGraph.whenReady { graph ->
    println "Task graph ready"
}

gradle.taskGraph.beforeTask { task ->
    println "About to execute task: ${task.name}"
}

gradle.taskGraph.afterTask { task, state ->
    println "Task ${task.name} completed, status: ${state.failure ? 'failed' : 'success'}
}

Performance Optimization Recommendations

1. Reduce work in configuration phase: Move unnecessary logic to execution phase
2. Use lazy initialization: Use tasks.register() instead of tasks.create()
3. Avoid I/O operations in configuration phase: Such as network requests, file reads/writes, etc.
4. Use configuration cache: Enable via --configuration-cache parameter