#SpringBatch java.util.function components

ConsumerItemWriter.java

package org.springframework.batch.item.function;

import java.util.List;
import java.util.function.Consumer;

import org.springframework.batch.item.ItemWriter;
import org.springframework.util.Assert;

public class ConsumerItemWriter<T> implements ItemWriter<T> {

	private Consumer<T> consumer;

	public ConsumerItemWriter(Consumer<T> consumer) {
		Assert.notNull(consumer, "A consumer is required");
		this.consumer = consumer;
	}

	@Override
	public void write(List<? extends T> items) throws Exception {
		items.forEach(this.consumer);
	}
}

PredicateFilteringItemProcessor.java

package org.springframework.batch.item.function;

import java.util.function.Predicate;

import org.springframework.batch.item.ItemProcessor;
import org.springframework.util.Assert;

public class PredicateFilteringItemProcessor<T> implements ItemProcessor<T, T> {

	private Predicate<T> predicate;

	public PredicateFilteringItemProcessor(Predicate<T> predicate) {
		Assert.notNull(predicate, "A predicate is required");
		this.predicate = predicate;
	}

	@Override
	public T process(T item) throws Exception {
		return this.predicate.test(item) ? item : null;
	}
}

SupplierItemReader.java

package org.springframework.batch.item.function;

import java.util.function.Supplier;

import org.springframework.batch.item.ItemReader;
import org.springframework.util.Assert;

public class SupplierItemReader<T> implements ItemReader<T> {

	private Supplier<T> supplier;

	public SupplierItemReader(Supplier<T> supplier) {
		Assert.notNull(supplier, "A supplier is required");
		this.supplier = supplier;
	}

	@Override
	public T read() throws Exception {
		return this.supplier.get();
	}
}