org.sfm.csv.CsvReader Maven / Gradle / Ivy

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package org.sfm.csv;

import org.sfm.csv.parser.*;
import org.sfm.utils.RowHandler;

import java.io.IOException;
import java.io.Reader;
import java.util.Iterator;
//IFJAVA8_START
import java.util.Spliterator;
import java.util.function.Consumer;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;
//IFJAVA8_END

public final class CsvReader implements Iterable {

	private final static CellConsumer DUMMY_CONSUMER = new CellConsumer() {

		@Override
		public void newCell(char[] chars, int offset, int length) {
		}

		@Override
		public void endOfRow() {
		}

		@Override
		public void end() {
		}
	};

	private final Reader reader;
	private final CsvCharConsumer consumer;

	public CsvReader(Reader reader, CsvCharConsumer charConsumer) {
		this.reader = reader;
		this.consumer = charConsumer;
	}

	/**
	 * parse cvs
	 * 
	 * @throws IOException
	 */
	public  CC parseAll(CC cellConsumer)
			throws IOException {
		do {
			consumer.parseAll(cellConsumer);
		} while (consumer.fillBuffer(reader));
		consumer.finish(cellConsumer);

		return cellConsumer;
	}

	/**
	 * parse cvs
	 *
	 * @throws IOException
	 */
	public boolean parseRow(CellConsumer cellConsumer)
			throws IOException {

		do {
			if (consumer.nextRow(cellConsumer)) {
				return true;
			}
		} while (consumer.fillBuffer(reader));

		consumer.finish(cellConsumer);
		return false;
	}


	public void skipRows(int n) throws IOException {
		parseRows(DUMMY_CONSUMER, n);
	}

	public  CC  parseRows(CC cellConsumer, int limit) throws IOException {
		for(int i = 0; i < limit; i++) {
			parseRow(cellConsumer);
		}
		return cellConsumer;
	}

	public > RH read(RH handler) throws IOException {
		parseAll(new StringArrayConsumer(handler));
		return handler;
	}

	public > RH read(RH handler, int limit) throws IOException {
		parseRows(new StringArrayConsumer(handler), limit);
		return handler;
	}

	@Override
	public Iterator iterator() {
		return new CsvStringArrayIterator(this);
	}

	//IFJAVA8_START
	public Stream stream() {
		return StreamSupport.stream(new CsvStringArraySpliterator(this), false);
	}

	private static class CsvStringArraySpliterator implements Spliterator {
		private final CsvReader reader;

		public CsvStringArraySpliterator(CsvReader csvReader) {
			this.reader = csvReader;
		}

		@Override
		public boolean tryAdvance(Consumer action) {
			try {
				return reader.parseRow(new StringArrayConsumer>((strings) -> action.accept(strings)));
			} catch (IOException e) {
				throw new RuntimeException(e);
			}
		}

		@Override
		public void forEachRemaining(Consumer action) {
			try {
				reader.parseAll(new StringArrayConsumer>((strings) -> action.accept(strings)));
			} catch (IOException e) {
				throw new RuntimeException(e);
			}
		}

		@Override
		public Spliterator trySplit() {
			return null;
		}

		@Override
		public long estimateSize() {
			return Long.MAX_VALUE;
		}

		@Override
		public int characteristics() {
			return Spliterator.ORDERED | Spliterator.NONNULL;
		}
	}

	//IFJAVA8_END

}