Java Support

ThinkCode provides comprehensive support for Java development, offering specialized tools, intelligent code assistance, and powerful features to enhance your productivity when building Java applications, from standalone programs to enterprise systems.

Getting Started

Setup and Configuration

ThinkCode automatically detects Java projects. For optimal experience:

Install Java Extension:
- ThinkCode will prompt to install the Java extension when you open a Java file
- Alternatively, open the Extensions view (Ctrl+Shift+X / Cmd+Shift+X) and search for "ThinkCode Java"
Install Java Development Kit (JDK):
- Ensure JDK is installed on your system
- ThinkCode will detect the JDK installation automatically
- Configure JDK version in settings if needed
Project Configuration:
- ThinkCode supports standard Java project structures
- Automatically recognizes Maven, Gradle, and Ant build files
- Configures the Java environment variables
Create a New Project:
- Command Palette (Ctrl+Shift+P / Cmd+Shift+P)
- Type "ThinkCode: Create New Project"
- Select Java from template categories
- Choose from templates:
  - Java Application
  - Java Library
  - Spring Boot Application
  - Jakarta EE Application
  - Android Project
  - Maven/Gradle Project

Code Intelligence

ThinkCode provides advanced intelligence for Java:

Auto-Completion: Context-aware suggestions for:
- Classes and methods
- Variables and fields
- Package imports
- API usage patterns
Type Information: Detailed type information with tooltips
Signature Help: Parameter info for methods and constructors
Quick Documentation: Access Javadoc directly in the editor

Example of Java code with intelligent assistance:

// ThinkCode provides intelligent assistance for Java
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import java.time.LocalDateTime;
 
/**
 * Represents a product in the e-commerce system
 */
public class Product {
    private String id;
    private String name;
    private String description;
    private double price;
    private int stockQuantity;
    private List<String> categories;
    private LocalDateTime createdAt;
    
    // ThinkCode provides constructor suggestions
    public Product(String name, double price) {
        this.id = java.util.UUID.randomUUID().toString();
        this.name = name;
        this.price = price;
        this.categories = new ArrayList<>();
        this.createdAt = LocalDateTime.now();
    }
    
    // ThinkCode offers getter/setter generation
    public String getId() {
        return id;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        this.name = name;
    }
    
    public String getDescription() {
        return description;
    }
    
    public void setDescription(String description) {
        this.description = description;
    }
    
    public double getPrice() {
        return price;
    }
    
    public void setPrice(double price) {
        this.price = price;
    }
    
    public int getStockQuantity() {
        return stockQuantity;
    }
    
    public void setStockQuantity(int stockQuantity) {
        this.stockQuantity = stockQuantity;
    }
    
    public List<String> getCategories() {
        return new ArrayList<>(categories);
    }
    
    public void addCategory(String category) {
        this.categories.add(category);
    }
    
    public LocalDateTime getCreatedAt() {
        return createdAt;
    }
    
    // ThinkCode understands method purpose and offers recommendations
    public boolean isInStock() {
        return stockQuantity > 0;
    }
    
    public double getDiscountedPrice(double discountPercentage) {
        return price - (price * discountPercentage / 100);
    }
}
 
// ThinkCode provides smart suggestions for service classes
class ProductService {
    private List<Product> products = new ArrayList<>();
    
    // ThinkCode understands streams and functional programming
    public List<Product> getProductsByCategory(String category) {
        return products.stream()
                .filter(p -> p.getCategories().contains(category))
                .sorted((p1, p2) -> p1.getName().compareTo(p2.getName()))
                .collect(Collectors.toList());
    }
    
    public List<Product> getProductsInPriceRange(double minPrice, double maxPrice) {
        return products.stream()
                .filter(p -> p.getPrice() >= minPrice && p.getPrice() <= maxPrice)
                .collect(Collectors.toList());
    }
    
    public void addProduct(Product product) {
        products.add(product);
    }
    
    public Product getProductById(String id) {
        return products.stream()
                .filter(p -> p.getId().equals(id))
                .findFirst()
                .orElse(null);
    }
}

Navigate your codebase efficiently:

Go to Definition: Jump to declarations
- Keyboard: F12 or Ctrl+Click / Cmd+Click
- Works across packages and dependencies
Find All References: Locate all usages of a symbol
- Keyboard: Shift+F12
- Results organized by file and location
Go to Implementation: Jump to implementations of interfaces
- Keyboard: Ctrl+F12 / Cmd+F12
Outline View: Explore the structure of Java files
- Keyboard: Ctrl+Shift+O / Cmd+Shift+O
- Shows classes, methods, fields, and more
Type Hierarchy View: View inheritance hierarchies
- Keyboard: Ctrl+Alt+H / Cmd+Option+H

Import Management

Efficient handling of Java imports:

Auto-Import: Automatically add missing imports
Organize Imports: Remove unused imports and organize
Import Completion: Intelligent package suggestions
Static Import Support: Assistance for static imports

Configure import behavior:

{
  "thinkcode.java.imports": {
    "autoOrganize": true,
    "starThreshold": 99,
    "staticStarThreshold": 99,
    "onSave": true,
    "importOrder": ["java", "javax", "org", "com", ""]
  }
}

AI-Powered Development Features

Smart Code Generation

Generate Java code with natural language prompts:

Method Generation:

Add a comment describing method purpose
Press Alt+I / Option+I for AI implementation

Example:

// Generate a method that validates an email address using regex
// Press Alt+I here and ThinkCode generates the implementation
public boolean isValidEmail(String email) {
    if (email == null || email.isEmpty()) {
        return false;
    }
    
    String emailRegex = "^[a-zA-Z0-9_+&*-]+(?:\\.[a-zA-Z0-9_+&*-]+)*@(?:[a-zA-Z0-9-]+\\.)+[a-zA-Z]{2,7}$";
    
    return email.matches(emailRegex);
}

Class Generation:
- Describe class purpose in a comment
- ThinkCode generates a complete class with fields and methods
Test Generation:
- Select method to test
- Right-click and select "Generate Unit Tests"
- ThinkCode generates JUnit tests for the method

Code Refactoring

AI-assisted refactoring capabilities:

Extract Method: Create a new method from selected code
Extract Variable: Create a variable from an expression
Rename Symbol: Intelligently rename variables, methods, and types
Optimize Imports: Organize and clean up imports
Generate Constructor: Create constructor from fields

Access refactoring tools:

Right-click in editor
Select "Refactor" menu
Choose desired refactoring operation

Documentation Assistant

Generate and maintain Java documentation:

Javadoc Generation: Auto-generate Javadoc comments
README Creation: Generate project documentation
API Documentation: Create API reference documentation
Examples: Generate example usage code

Example of AI-assisted documentation:

// Place cursor here and use Command Palette > "Generate Documentation"
/**
 * Processes a collection of items using the specified filter and transformer.
 * 
 * <p>This method processes each item in the input collection, applying the filter predicate 
 * to determine which items to include, and then applying the transformation function to each 
 * filtered item. If parallel processing is enabled, operations will be performed concurrently.</p>
 * 
 * @param <T> the type of input items
 * @param <R> the type of output items
 * @param items the collection of items to process
 * @param filter the predicate to filter items (items that match the predicate are processed)
 * @param transformer the function to transform filtered items to output type
 * @param parallel whether to process items in parallel
 * @return a list of transformed items that passed the filter
 * @throws NullPointerException if items, filter, or transformer is null
 * @throws IllegalArgumentException if the collection is empty
 * 
 * @example
 * <pre>{@code
 * List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 * 
 * // Get squares of even numbers
 * List<Integer> evenSquares = processItems(
 *     numbers,
 *     n -> n % 2 == 0,    // Filter: only even numbers
 *     n -> n * n,         // Transform: square the number
 *     true                // Process in parallel
 * );
 * 
 * // evenSquares contains: [4, 16, 36, 64, 100]
 * }</pre>
 */
public <T, R> List<R> processItems(
        Collection<T> items,
        Predicate<T> filter,
        Function<T, R> transformer,
        boolean parallel) {
    
    // Implementation...
}

Project Management

Build System Integration

Seamless integration with Java build systems:

Maven Support:
- POM file editing assistance
- Dependency management
- Lifecycle command execution
- Profile handling
Gradle Support:
- Build script intelligence
- Task execution
- Dependency management
- Multi-project builds
Ant Support:
- Build file editing
- Target execution
- Property management

Access build tools:

Open the Build view in sidebar
Select build commands to execute
View build task results

Project Explorer

Navigate complex Java projects:

Package View: Organized by Java packages
Project View: Organized by project structure
Type Hierarchy: View inheritance relationships
Class Structure: View methods and fields

Debugging and Testing

Debugging

Powerful Java debugging capabilities:

Integrated Debugger: Debug Java applications directly
Breakpoints:
- Conditional breakpoints
- Exception breakpoints
- Method breakpoints
- Field watchpoints
Variable Inspection: Examine variables and objects
Expression Evaluation: Evaluate Java expressions during debugging

Example launch configuration:

// .vscode/launch.json
{
  "version": "0.2.0",
  "configurations": [
    {
      "type": "thinkcode-java",
      "request": "launch",
      "name": "Launch Java Program",
      "mainClass": "${file}",
      "args": [],
      "vmArgs": ["-Xmx512m"],
      "projectName": "my-project"
    },
    {
      "type": "thinkcode-java",
      "request": "attach",
      "name": "Attach to Remote Java Program",
      "hostName": "localhost",
      "port": 5005
    }
  ]
}

Testing

Integrated support for Java testing:

Test Explorer: View and run tests with visual UI
Test Discovery: Automatically find tests in your project
Test Generation: AI-assisted test creation
Coverage Visualization: See code coverage in editor

Supported test frameworks:

JUnit 4 and 5
TestNG
Spock

Run tests with:

Click on test gutter icons
Right-click on test method or class
Use Test Explorer view

Code Quality and Analysis

Linting and Static Analysis

Integrated code quality tools:

Checkstyle Integration: Enforce coding standards
PMD Support: Detect common coding issues
SpotBugs: Find potential bugs
Error Lens: See errors and warnings inline

Configure quality tools:

{
  "thinkcode.java.codeQuality": {
    "enabled": true,
    "checkstyle": {
      "enabled": true,
      "configFile": "${workspaceFolder}/checkstyle.xml",
      "version": "8.44"
    },
    "pmd": {
      "enabled": true,
      "rulesets": ["category/java/bestpractices.xml", "category/java/errorprone.xml"]
    },
    "spotbugs": {
      "enabled": true,
      "excludeFilter": "${workspaceFolder}/spotbugs-exclude.xml"
    }
  }
}

Code Formatting

Maintain consistent code style:

Format Document: Apply formatting rules
Format Selection: Format selected code
Format on Save: Automatically format while saving
EditorConfig Support: Use EditorConfig for style rules

Example formatter configuration:

{
  "thinkcode.java.format": {
    "enabled": true,
    "onSave": true,
    "settings": {
      "profile": "GoogleStyle",
      "tabSize": 4,
      "insertSpaces": true,
      "lineSeparator": "LF",
      "indentationSize": 4
    }
  }
}

Enterprise Java Development

Spring Framework Support

Specialized tools for Spring development:

Spring Boot Support:
- Starter dependency suggestions
- Configuration property completion
- Actuator endpoint intelligence
- Spring Boot DevTools integration
Spring MVC:
- Controller mapping detection
- RequestMapping intelligence
- View navigation
- Path variable completion
Spring Data:
- Repository method completion
- Query method generation
- Entity relationship visualization
- Database schema integration

Example of Spring Boot application with intelligent assistance:

// ThinkCode provides intelligent assistance for Spring
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.web.bind.annotation.*;
 
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.validation.Valid;
import java.util.List;
import java.util.Optional;
 
@SpringBootApplication
public class EcommerceApplication {
    public static void main(String[] args) {
        SpringApplication.run(EcommerceApplication.class, args);
    }
    
    // ThinkCode provides Bean configuration suggestions
    @Bean
    public ModelMapper modelMapper() {
        return new ModelMapper();
    }
}
 
// ThinkCode provides JPA entity suggestions
@Entity
class Product {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    
    private String name;
    private String description;
    private double price;
    private int stockQuantity;
    
    // Getters and setters...
}
 
// ThinkCode provides Spring Data interface completion
interface ProductRepository extends JpaRepository<Product, Long> {
    // ThinkCode provides method name suggestions for queries
    List<Product> findByNameContainingIgnoreCase(String name);
    
    List<Product> findByPriceBetween(double minPrice, double maxPrice);
    
    Optional<Product> findByNameIgnoreCase(String name);
    
    // ThinkCode provides custom query suggestions
    @Query("SELECT p FROM Product p WHERE p.stockQuantity > 0 ORDER BY p.price ASC")
    List<Product> findInStockProductsOrderByPriceAsc();
}
 
// ThinkCode provides REST controller assistance
@RestController
@RequestMapping("/api/products")
class ProductController {
    private final ProductRepository productRepository;
    private final ModelMapper modelMapper;
    
    // ThinkCode provides constructor injection
    public ProductController(ProductRepository productRepository, ModelMapper modelMapper) {
        this.productRepository = productRepository;
        this.modelMapper = modelMapper;
    }
    
    // ThinkCode provides endpoint method suggestions
    @GetMapping
    public List<ProductDto> getAllProducts() {
        return productRepository.findAll().stream()
                .map(product -> modelMapper.map(product, ProductDto.class))
                .collect(Collectors.toList());
    }
    
    @GetMapping("/{id}")
    public ResponseEntity<ProductDto> getProduct(@PathVariable Long id) {
        return productRepository.findById(id)
                .map(product -> modelMapper.map(product, ProductDto.class))
                .map(ResponseEntity::ok)
                .orElse(ResponseEntity.notFound().build());
    }
    
    @PostMapping
    public ResponseEntity<ProductDto> createProduct(@Valid @RequestBody ProductDto productDto) {
        Product product = modelMapper.map(productDto, Product.class);
        Product savedProduct = productRepository.save(product);
        
        return ResponseEntity
            .created(URI.create("/api/products/" + savedProduct.getId()))
            .body(modelMapper.map(savedProduct, ProductDto.class));
    }
    
    @PutMapping("/{id}")
    public ResponseEntity<ProductDto> updateProduct(
            @PathVariable Long id, 
            @Valid @RequestBody ProductDto productDto) {
        
        if (!productRepository.existsById(id)) {
            return ResponseEntity.notFound().build();
        }
        
        Product product = modelMapper.map(productDto, Product.class);
        product.setId(id);
        Product updatedProduct = productRepository.save(product);
        
        return ResponseEntity.ok(modelMapper.map(updatedProduct, ProductDto.class));
    }
    
    @DeleteMapping("/{id}")
    public ResponseEntity<Void> deleteProduct(@PathVariable Long id) {
        if (!productRepository.existsById(id)) {
            return ResponseEntity.notFound().build();
        }
        
        productRepository.deleteById(id);
        return ResponseEntity.noContent().build();
    }
}

Jakarta EE Support

Tools for Jakarta EE (formerly Java EE) development:

Servlet Support: Servlet API intelligence
JAX-RS: RESTful web services assistance
JPA: Persistence intelligence
EJB: Enterprise bean support
JSF: JavaServer Faces development

Enterprise Integration

Support for enterprise integration patterns:

JMS/MQ: Messaging system integration
SOAP/Web Services: WSDL and SOAP support
GraphQL: Schema development assistance
gRPC: Protocol buffer support

Mobile and Desktop Application Development

JavaFX Support

Tools for JavaFX desktop applications:

FXML Support: Intelligent FXML editing
Scene Builder Integration: Visual UI design
CSS Styling: JavaFX CSS assistance
Event Handling: Automatic handler generation

Android Development

Support for Android application development:

Android SDK Integration: SDK management
Gradle for Android: Android-specific build support
Layout Editor: Android XML layout assistance
Resource Management: Android resource handling

Example Android activity with intelligent assistance:

// ThinkCode provides intelligent assistance for Android
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
 
import androidx.appcompat.app.AppCompatActivity;
import androidx.lifecycle.ViewModelProvider;
 
public class ProductDetailActivity extends AppCompatActivity {
    private ProductViewModel viewModel;
    private TextView nameTextView;
    private TextView priceTextView;
    private TextView descriptionTextView;
    private ImageView productImageView;
    private Button addToCartButton;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_product_detail);
        
        // ThinkCode provides View binding suggestions
        nameTextView = findViewById(R.id.product_name);
        priceTextView = findViewById(R.id.product_price);
        descriptionTextView = findViewById(R.id.product_description);
        productImageView = findViewById(R.id.product_image);
        addToCartButton = findViewById(R.id.add_to_cart_button);
        
        // ThinkCode understands Android ViewModel patterns
        viewModel = new ViewModelProvider(this).get(ProductViewModel.class);
        
        // Get product ID from intent
        String productId = getIntent().getStringExtra("PRODUCT_ID");
        if (productId == null) {
            Toast.makeText(this, "Product not found", Toast.LENGTH_SHORT).show();
            finish();
            return;
        }
        
        // ThinkCode offers LiveData observation suggestions
        viewModel.getProduct(productId).observe(this, product -> {
            if (product == null) {
                Toast.makeText(this, "Product not found", Toast.LENGTH_SHORT).show();
                finish();
                return;
            }
            
            // Update UI
            nameTextView.setText(product.getName());
            priceTextView.setText(String.format("$%.2f", product.getPrice()));
            descriptionTextView.setText(product.getDescription());
            
            // Load image with Glide
            Glide.with(this)
                 .load(product.getImageUrl())
                 .placeholder(R.drawable.placeholder)
                 .error(R.drawable.error)
                 .into(productImageView);
                 
            // Update button state
            updateCartButton(product.isInStock());
        });
        
        // ThinkCode provides click listener suggestions
        addToCartButton.setOnClickListener(v -> {
            viewModel.addToCart(productId).observe(this, success -> {
                if (success) {
                    Toast.makeText(this, "Added to cart", Toast.LENGTH_SHORT).show();
                    addToCartButton.setEnabled(false);
                    addToCartButton.setText(R.string.in_cart);
                } else {
                    Toast.makeText(this, "Failed to add to cart", Toast.LENGTH_SHORT).show();
                }
            });
        });
    }
    
    private void updateCartButton(boolean inStock) {
        if (inStock) {
            addToCartButton.setEnabled(true);
            addToCartButton.setText(R.string.add_to_cart);
        } else {
            addToCartButton.setEnabled(false);
            addToCartButton.setText(R.string.out_of_stock);
        }
    }
}

Java Performance Tools

Performance Analysis

Identify and optimize Java performance:

Profiler Integration: CPU and memory profiling
Heap Analysis: Detect memory leaks
Thread Visualization: View thread activity
GC Monitoring: Track garbage collection activity

Access performance tools:

Command Palette
Type "ThinkCode: Profile Java Application"
Select profiling type

Example JMH benchmark with intelligent assistance:

// ThinkCode provides intelligent performance analysis
import org.openjdk.jmh.annotations.*;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;
 
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.concurrent.TimeUnit;
 
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@Warmup(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
@Fork(1)
@State(Scope.Benchmark)
public class ListPerformanceBenchmark {
    private static final int LIST_SIZE = 10_000;
    
    @Benchmark
    public List<Integer> arrayListCreation() {
        List<Integer> list = new ArrayList<>(LIST_SIZE);
        for (int i = 0; i < LIST_SIZE; i++) {
            list.add(i);
        }
        return list;
    }
    
    @Benchmark
    public List<Integer> linkedListCreation() {
        List<Integer> list = new LinkedList<>();
        for (int i = 0; i < LIST_SIZE; i++) {
            list.add(i);
        }
        return list;
    }
    
    @Benchmark
    public int arrayListRandomAccess(ArrayListState state) {
        int sum = 0;
        for (int i = 0; i < 1000; i++) {
            int index = (i * 17) % LIST_SIZE;
            sum += state.list.get(index);
        }
        return sum;
    }
    
    @Benchmark
    public int linkedListRandomAccess(LinkedListState state) {
        int sum = 0;
        for (int i = 0; i < 1000; i++) {
            int index = (i * 17) % LIST_SIZE;
            sum += state.list.get(index);
        }
        return sum;
    }
    
    @State(Scope.Benchmark)
    public static class ArrayListState {
        List<Integer> list = new ArrayList<>(LIST_SIZE);
        
        @Setup
        public void setup() {
            for (int i = 0; i < LIST_SIZE; i++) {
                list.add(i);
            }
        }
    }
    
    @State(Scope.Benchmark)
    public static class LinkedListState {
        List<Integer> list = new LinkedList<>();
        
        @Setup
        public void setup() {
            for (int i = 0; i < LIST_SIZE; i++) {
                list.add(i);
            }
        }
    }
    
    public static void main(String[] args) throws Exception {
        Options options = new OptionsBuilder()
            .include(ListPerformanceBenchmark.class.getSimpleName())
            .build();
        new Runner(options).run();
    }
}

Optimization Suggestions

Get intelligent suggestions for improving performance:

Collection Selection: Choose appropriate collections
Concurrency Improvements: Optimize multi-threaded code
I/O Optimization: Improve file and network operations
Memory Management: Reduce object allocation

Java Ecosystem Integration

Database Connectivity

Support for database development:

JDBC Support: Database connection assistance
Connection Management: Configure and manage connections
SQL Integration: SQL editing and execution
ORM Support: JPA, Hibernate, and MyBatis integration

Cloud Integration

Support for Java cloud deployments:

Spring Cloud: Microservice development
AWS SDK: Amazon Web Services integration
Azure SDK: Microsoft Azure integration
Google Cloud: GCP integration

Customization

Extension Points

Extend ThinkCode's Java support:

Custom Code Generators: Implement code generation templates
Build System Integration: Configure custom build steps
Linting Rules: Add custom checkstyle/PMD rules
Language Features: Add support for custom annotations

Configuration Options

Comprehensive configuration for Java development:

{
  "thinkcode.java": {
    "home": null,
    "jdt": {
      "ls": {
        "vmargs": "-XX:+UseParallelGC -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90 -Dsun.zip.disableMemoryMapping=true -Xmx1G -Xms100m"
      }
    },
    "errors": {
      "incompleteClasspath": {
        "severity": "warning"
      }
    },
    "configuration": {
      "updateBuildConfiguration": "automatic",
      "maven": {
        "userSettings": null,
        "globalSettings": null
      },
      "gradle": {
        "home": null,
        "wrapperEnabled": true,
        "version": null,
        "jvmArguments": null
      }
    },
    "format": {
      "enabled": true,
      "settings": {
        "url": "",
        "profile": "GoogleStyle"
      },
      "onType": true
    },
    "refactoring": {
      "renameFromFile": true
    },
    "completion": {
      "enabled": true,
      "guessMethodArguments": true,
      "favoriteStaticMembers": [],
      "importOrder": ["java", "javax", "com", "org", ""]
    },
    "server": {
      "launchMode": "Hybrid"
    }
  }
}