Spring Batch Exposed ItemReader

Kotlin Exposed ItemReader For Spring Batch

Usage

Requires

• Kotlin (above Java 17)
• Spring Batch

Get Started

Add to build.gradle.kts
x.y.z should be replace into the latest version.

repositories {
    ...
    maven { url = uri("https://jitpack.io") }
}
...
dependencies {
    ...
    implementation("com.github.tykann.spring-batch-exposed:spring-batch-exposed-reader:x.y.z")
}

Type of item is always ResultRow of Exposed.

ExposedPagingItemReader

Common paging reader using offset.

@Bean(READER_NAME)
@StepScope
fun reader(): ExposedPagingItemReader {
	return ExposedPagingItemReader(CHUNK_SIZE) {
		Store
			.join(Book, JoinType.INNER, Book.storeId, Store.id)
			.selectAll()
			.orderBy(Store.id to SortOrder.ASC)
	}
}

ExposedNoOffsetPagingItemReader

No offset query is required due to the performance problem of the paging query.

@Bean(READER_NAME)
@StepScope
fun reader(): ExposedNoOffsetPagingItemReader {
	val options = ExposedNoOffsetIdLongOptions(Store.id to SortOrder.ASC)
	return ExposedNoOffsetPagingItemReader(options, CHUNK_SIZE) {
		Store
			.join(Book, JoinType.INNER, Book.storeId, Store.id)
			.selectAll()
	}
}