Implement comprehensive multi-format DataFrame Spring integration with Spring Data patterns

build.gradle.kts

@@ -63,6 +63,7 @@ dependencies {
 
     // experimental, so not included by default:
     // api(projects.dataframeOpenapi)
+    // api(projects.dataframeSpring)
 
 //    kover(projects.core)
 //    kover(projects.dataframeArrow)
@@ -162,6 +163,13 @@ val modulesUsingJava11 = with(projects) {
     )
 }.map { it.path }
 
+val modulesUsingJava17 = with(projects) {
+    setOf(
+        dataframeSpring,
+        examples.ideaExamples.springbootDataframeWeb,
+    )
+}.map { it.path }
+
 allprojects {
     if (path in modulesUsingJava11) {
         tasks.withType<KotlinCompile> {
@@ -175,6 +183,19 @@ allprojects {
             targetCompatibility = JavaVersion.VERSION_11.toString()
             options.release.set(11)
         }
+    }
+    if (path in modulesUsingJava17) {
+        tasks.withType<KotlinCompile> {
+            compilerOptions {
+                jvmTarget = JvmTarget.JVM_17
+                freeCompilerArgs.add("-Xjdk-release=17")
+            }
+        }
+        tasks.withType<JavaCompile> {
+            sourceCompatibility = JavaVersion.VERSION_17.toString()
+            targetCompatibility = JavaVersion.VERSION_17.toString()
+            options.release.set(17)
+        }
     } else {
         tasks.withType<KotlinCompile> {
             compilerOptions {

data/spring/customers.csv

@@ -0,0 +1,13 @@
+id,name,country,email
+1,Alice Johnson,USA,alice@example.com
+2,Bob Smith,Canada,bob@example.ca
+3,Charlie Davis,USA,charlie@example.com
+4,Diana Evans,UK,diana@example.co.uk
+5,Edward Wilson,USA,edward@example.com
+6,Fiona Brown,Australia,fiona@example.com.au
+7,George Miller,Germany,george@example.de
+8,Helen Clark,USA,helen@example.com
+9,Ian Thompson,Ireland,ian@example.ie
+10,Julia Roberts,USA,julia@example.com
+11,Kevin Lee,Canada,kevin@example.ca
+12,Linda Perez,Spain,linda@example.es

data/spring/sales.csv

@@ -0,0 +1,13 @@
+sale_id,customer_id,product,value,date
+1001,1,Laptop,1200.50,2025-01-05
+1002,2,Phone,799.99,2025-01-10
+1003,3,Tablet,450.00,2025-02-14
+1004,4,Headphones,149.99,2025-02-20
+1005,5,Monitor,299.49,2025-03-01
+1006,6,Keyboard,89.99,2025-03-12
+1007,7,Mouse,49.95,2025-03-15
+1008,8,Smartwatch,199.00,2025-04-01
+1009,9,Camera,650.75,2025-04-12
+1010,10,Printer,220.00,2025-04-20
+1011,11,Speaker,130.00,2025-05-02
+1012,12,Router,99.99,2025-05-10

dataframe-spring/INTEGRATION_GUIDE.md

@@ -0,0 +1,141 @@
+# DataFrame Spring Integration Guide
+
+## Quick Start
+
+### 1. Add Dependency
+
+Add the DataFrame Spring module to your project:
+
+```kotlin
+// build.gradle.kts
+dependencies {
+    implementation("org.jetbrains.kotlinx:dataframe-spring:${dataframeVersion}")
+}
+```
+
+### 2. Enable Component Scanning
+
+```kotlin
+@Configuration
+@ComponentScan(basePackages = ["org.jetbrains.kotlinx.dataframe.spring"])
+class AppConfiguration
+```
+
+### 3. Use @DataSource Annotation
+
+```kotlin
+@Component
+class CustomerService {
+    @DataSource(csvFile = "customers.csv")
+    lateinit var customers: DataFrame<CustomerRow>
+
+    @DataSource(csvFile = "orders.csv", delimiter = ';')
+    lateinit var orders: DataFrame<OrderRow>
+
+    fun analyzeCustomers() {
+        println("Total customers: ${customers.rowsCount()}")
+        // Access data using DataFrame API
+    }
+}
+```
+
+### 4. Define Your Data Schema
+
+```kotlin
+@DataSchema
+interface CustomerRow {
+    val id: Int
+    val name: String
+    val email: String
+    val registrationDate: String
+}
+```
+
+## Advanced Configuration
+
+### Manual Bean Registration
+
+If you prefer manual configuration:
+
+```kotlin
+@Configuration
+class DataFrameConfig {
+    @Bean
+    fun dataFramePostProcessor() = DataFramePostProcessor()
+}
+```
+
+### Custom File Locations
+
+Use Spring's property placeholders:
+
+```kotlin
+@DataSource(csvFile = "\${app.data.customers.file}")
+lateinit var customers: DataFrame<CustomerRow>
+```
+
+### Error Handling
+
+The post-processor provides detailed error messages:
+
+```kotlin
+// File not found
+RuntimeException: Failed to process @DataSource annotations for bean 'customerService'
+Caused by: IllegalArgumentException: CSV file not found: /path/to/customers.csv
+
+// Wrong property type
+IllegalArgumentException: Property 'data' is annotated with @DataSource but is not a DataFrame type
+
+// CSV parsing error
+RuntimeException: Failed to read CSV file 'customers.csv' for property 'customers'
+```
+
+## Best Practices
+
+1. **Use meaningful file paths**: Place CSV files in `src/main/resources/data/`
+2. **Define data schemas**: Use `@DataSchema` for type safety
+3. **Handle initialization**: Use `lateinit var` for DataFrame properties
+4. **Validate data**: Add business logic validation after initialization
+5. **Resource management**: CSV files are loaded once during bean initialization
+
+## Troubleshooting
+
+### Common Issues
+
+1. **ClassNotFoundException**: Ensure Spring dependencies are available
+2. **FileNotFoundException**: Check CSV file paths are correct
+3. **PropertyAccessException**: Ensure DataFrame properties are `lateinit var`
+4. **NoSuchBeanDefinitionException**: Enable component scanning or register manually
+
+### Debug Tips
+
+- Enable Spring debug logging: `logging.level.org.springframework=DEBUG`
+- Check bean post-processor registration: Look for `DataFramePostProcessor` in logs
+- Verify CSV file locations: Use absolute paths for testing
+
+## Integration with Spring Boot
+
+```kotlin
+@SpringBootApplication
+@ComponentScan(basePackages = ["your.package", "org.jetbrains.kotlinx.dataframe.spring"])
+class Application
+
+fun main(args: Array<String>) {
+    runApplication<Application>(*args)
+}
+```
+
+## Testing
+
+```kotlin
+@SpringBootTest
+class DataFrameServiceTest {
+    @Autowired
+    private lateinit var customerService: CustomerService
+
+    @Test
+    fun `should load customer data`() {
+        assertTrue(customerService.customers.rowsCount() > 0)
+    }
+}
+```