Module 01: Development Environment Setup

Goal: Set up a complete development environment that can compile and run Java Android projects.

Frontend vs. Android Development Environment

Frontend	Android	Description
Node.js	JDK (Java Development Kit)	Runtime environment
VS Code / WebStorm	Android Studio (based on IntelliJ)	IDE
npm / yarn / pnpm	Gradle	Build tool + dependency management
`package.json`	`build.gradle`	Project config + dependency declaration
`node_modules/`	`.gradle/` + Maven local repo	Dependency cache
Browser DevTools	Android Studio Debugger + Logcat	Debugging tools
Chrome / Firefox	Android Emulator / Physical device	Runtime target

1. Install JDK

Android development requires JDK. Android Studio comes with JetBrains Runtime, but it's recommended to install separately for easier management.

Recommended Versions

JDK 17: Minimum requirement for current Android Gradle Plugin 8.x, also compatible with most legacy projects
JDK 21: Supported by newer AGP, preferred for new projects

Legacy Project Note: If you're taking over a project using an older Gradle version (like 6.x or 7.x), you may need JDK 11 or even JDK 8. Read the project documentation first before deciding.

Installation

Windows (recommended: Scoop or manual download):

bash

# Using Scoop
scoop bucket add java
scoop install temurin17-jdk

# Or download from Adoptium: https://adoptium.net/

macOS (recommended: Homebrew):

bash

brew install --cask temurin@17

Linux (Ubuntu/Debian):

bash

sudo apt install openjdk-17-jdk

Verify Installation

bash

java -version
# Should show: openjdk version "17.x.x"

javac -version
# Should show: javac 17.x.x

Environment Variables

bash

# Windows (PowerShell, permanent)
[System.Environment]::SetEnvironmentVariable("JAVA_HOME", "C:\path\to\jdk-17", "User")

# macOS / Linux (~/.zshrc or ~/.bashrc)
export JAVA_HOME=$(/usr/libexec/java_home -v 17)
export PATH=$JAVA_HOME/bin:$PATH

2. Install Android Studio

Download

Download the latest Android Studio from the official website: https://developer.android.com/studio

Choose the latest stable version (e.g., Hedgehog 2023.1, Iguana 2023.2, Jellyfish 2023.3, etc.).

First Launch Configuration

Installation Type: Choose "Standard"
UI Theme: Personal preference (frontend developers usually prefer Dark theme)
SDK Components: Default selections are fine, ensure these are checked:
- Android SDK
- Android SDK Platform
- Android Virtual Device (AVD)

Getting Familiar with the IDE

Android Studio is based on IntelliJ IDEA. If you're a VS Code user, note these differences:

VS Code Action	Android Studio Equivalent	Shortcut
Command Palette	Find Action	`Ctrl+Shift+A` (Win) / `Cmd+Shift+A` (Mac)
File Search	Navigate to File	`Ctrl+Shift+N` / `Cmd+Shift+O`
Global Search	Find in Files	`Ctrl+Shift+F` / `Cmd+Shift+F`
Terminal	Terminal	`Alt+F12` / `Option+F12`
Sidebar	Project Panel	`Alt+1` / `Cmd+1`

Tip: You can switch to VS Code keymap in File → Settings → Keymap.

3. Android SDK Management

SDK Manager

Open via: File → Settings → Languages & Frameworks → Android SDK (on Mac: Android Studio → Settings)

The SDK has three tabs:

SDK Platforms

Check the latest Android 14 (API 34) or higher
If the legacy project you're taking over has a lower compileSdkVersion (e.g., 28, 30), download those versions too
API Level Reference (common):

Android Version	API Level	Codename
Android 8.0	26	Oreo
Android 9.0	28	Pie
Android 10	29	Q
Android 11	30	R
Android 12	31	S
Android 13	33	Tiramisu
Android 14	34	Upside Down Cake
Android 15	35	Vanilla Ice Cream

SDK Tools

Make sure to install:

Android SDK Build-Tools (latest version)
Android SDK Platform-Tools (includes adb command)
Android SDK Command-line Tools
Android Emulator

SDK Update Sites

Keep defaults.

SDK Path

Default SDK installation location:

Windows: C:\Users\<username>\AppData\Local\Android\Sdk
macOS: ~/Library/Android/sdk
Linux: ~/Android/Sdk

Remember this path — you'll need it when configuring environment variables:

bash

# macOS / Linux
export ANDROID_HOME=~/Library/Android/sdk
export PATH=$ANDROID_HOME/platform-tools:$PATH
export PATH=$ANDROID_HOME/emulator:$PATH

4. Create Your First Project

Via Android Studio

File → New → New Project
Choose Empty Views Activity
Fill in project info:
- Name: HelloAndroid
- Package name: com.example.helloandroid
- Language: Java (this tutorial focuses on Java)
- Minimum SDK: API 24 (Android 7.0, covers 95%+ devices)
Click Finish

Key Files

app/
├── src/main/
│   ├── java/com/example/helloandroid/
│   │   └── MainActivity.java      ← Main entry point
│   ├── res/
│   │   ├── layout/
│   │   │   └── activity_main.xml  ← UI layout
│   │   └── values/
│   │       ├── strings.xml        ← String resources
│   │       ├── colors.xml         ← Color definitions
│   │       └── themes.xml         ← Theme config
│   └── AndroidManifest.xml        ← App manifest
└── build.gradle                   ← Module-level build config

5. Run the App

Android Emulator

Open Device Manager: Tools → Device Manager
Click Create Device
Choose a device template (e.g., Pixel 7)
Download a system image (recommend Android 14 / API 34, x86_64)
Click Finish
Click the ▶️ button to start the emulator

Real Device

Enable Developer Options: Go to Settings → About Phone, tap "Build Number" 7 times
Enable USB Debugging: Settings → Developer Options → USB Debugging
Connect via USB, authorize the computer
The device will appear in Android Studio's device dropdown

Run

Click the green ▶️ button (or Shift+F10), choose the target device, and wait for compilation and installation.

ADB Commands

bash

# List connected devices
adb devices

# Install APK
adb install app/build/outputs/apk/debug/app-debug.apk

# View logs
adb logcat

# Filter logs by tag
adb logcat -s "MainActivity"

# Enter device shell
adb shell

# Screenshot
adb exec-out screencap -p > screenshot.png

6. Gradle Configuration

Gradle is Android's build system — similar to frontend build tools like Vite or Webpack, but more powerful.

Two build.gradle Files

Project-level build.gradle (root directory):

groovy

// Top-level build file
plugins {
    id 'com.android.application' version '8.2.0' apply false
}

Module-level app/build.gradle:

groovy

plugins {
    id 'com.android.application'
}

android {
    namespace 'com.example.helloandroid'
    compileSdk 34

    defaultConfig {
        applicationId "com.example.helloandroid"
        minSdk 24
        targetSdk 34
        versionCode 1
        versionName "1.0"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation 'androidx.appcompat:appcompat:1.6.1'
    implementation 'com.google.android.material:material:1.11.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
}

Key Concepts

Gradle Concept	Frontend Equivalent	Description
`dependencies {}`	`package.json` dependencies	Dependency declaration
`compileSdk`	TypeScript target	Compilation target API level
`minSdk`	browserslist	Minimum supported Android version
`buildTypes`	`NODE_ENV`	Build variants (debug/release)
`applicationId`	App bundle ID	Unique app identifier

Sync Gradle

After modifying build.gradle, click the Sync Now banner at the top, or: File → Sync Project with Gradle Files

Common Commands

bash

# Clean build
./gradlew clean

# Build debug APK
./gradlew assembleDebug

# Build release APK
./gradlew assembleRelease

# Install to device
./gradlew installDebug

# Run tests
./gradlew test

# Run lint checks
./gradlew lint

Common Environment Issues

When setting up the environment or opening a legacy project, you may encounter these common issues.

Gradle Sync Failures

Error	Cause	Solution
`Could not find com.android.tools.build:gradle:X.X.X`	AGP version incompatible with Gradle	Check the AGP/Gradle compatibility table in Module 03
`Unsupported class file major version XX`	JDK version mismatch	Switch to the JDK required by the project (usually 17 or 11)
`Could not resolve all files for configuration`	Dependency download failed	Check network, proxy, or mirror configuration
`SDK location not found`	SDK path not configured	Check/create `local.properties`
`Minimum supported Gradle version is X.Y`	Gradle Wrapper version too old	Upgrade Gradle Wrapper per compatibility table

bash

# Stop the Gradle daemon to resolve many cache-related issues
./gradlew --stop

# Clean build cache
./gradlew clean

# Refresh dependencies
./gradlew build --refresh-dependencies

Emulator / Device Connection

bash

# adb cannot see the device
adb kill-server
adb start-server
adb devices

# Wireless debugging disconnected
adb connect <phone-ip>:5555

# APK install failed (signature conflict or downgrade)
adb install -r -d app-debug.apk

JDK Version Switching

Android Studio lets you configure the JDK per project:

File → Settings → Build, Execution, Deployment → Build Tools → Gradle → Gradle JDK

Frontend analogy: This is similar to .nvmrc + nvm use; each Android project should pin its own JDK.

Gradle Daemon and Cache

The Gradle Daemon is like node_modules cache — it speeds up subsequent builds but consumes memory:

bash

# List running daemons
./gradlew --status

# Stop all daemons
./gradlew --stop

# Delete Gradle cache (like deleting node_modules/.cache)
rm -rf ~/.gradle/caches/

Quick Reference

Cannot find SDK: Ensure ANDROID_HOME environment variable is set correctly
Emulator too slow: Enable HAXM (Intel) or HAXM equivalent; or use a physical device
Gradle sync fails: Check internet connection; Gradle needs to download dependencies
Compilation errors: Run ./gradlew clean first
Device not recognized: Check USB debugging authorization; try adb kill-server && adb start-server

Next Steps

Environment setup is complete! Now let's learn the Java basics.

Module 01: Development Environment Setup ​

Frontend vs. Android Development Environment ​

1. Install JDK ​

Recommended Versions ​

Installation ​

Verify Installation ​

Environment Variables ​

2. Install Android Studio ​

Download ​

First Launch Configuration ​

Getting Familiar with the IDE ​

3. Android SDK Management ​

SDK Manager ​

SDK Platforms ​

SDK Tools ​

SDK Update Sites ​

SDK Path ​

4. Create Your First Project ​

Via Android Studio ​

Key Files ​

5. Run the App ​

Android Emulator ​

Real Device ​

Run ​

ADB Commands ​

6. Gradle Configuration ​

Two build.gradle Files ​

Key Concepts ​

Sync Gradle ​

Common Commands ​

Common Environment Issues ​

Gradle Sync Failures ​

Emulator / Device Connection ​

JDK Version Switching ​

Gradle Daemon and Cache ​

Quick Reference ​

Next Steps ​

Module 01: Development Environment Setup

Frontend vs. Android Development Environment

1. Install JDK

Recommended Versions

Installation

Verify Installation

Environment Variables

2. Install Android Studio

Download

First Launch Configuration

Getting Familiar with the IDE

3. Android SDK Management

SDK Manager

SDK Platforms

SDK Tools

SDK Update Sites

SDK Path

4. Create Your First Project

Via Android Studio

Key Files

5. Run the App

Android Emulator

Real Device

Run

ADB Commands

6. Gradle Configuration

Two build.gradle Files

Key Concepts

Sync Gradle

Common Commands

Common Environment Issues

Gradle Sync Failures

Emulator / Device Connection

JDK Version Switching

Gradle Daemon and Cache

Quick Reference

Next Steps