[Java] Orc File

public static <T> Writer makeOrcWriter(String path, Class<T> clazz) throws IOException {
	FileUtils.delete(path);

	Configuration conf = new Configuration(false);
	FileSystem fs = FileSystem.get(conf);

	return OrcFile.createWriter(new Path(path),
		OrcFile.writerOptions(conf)
			.inspector(ObjectInspectorFactory.getReflectionObjectInspector(clazz,
				ObjectInspectorFactory.ObjectInspectorOptions.JAVA))
			.fileSystem(fs)
	);
}
    
public static void delete(String path) {
	new File(path).delete();
}

import java.io.Closeable;
import java.io.File;
import java.io.IOException;
import java.util.List;

import org.apache.hadoop.hive.ql.io.orc.Writer;

import lombok.Getter;


@Getter
public class OrcFileWriter <T> implements Closeable {
	private String path;
	private Class<T> clazz;

	private Writer writer;
	private File file;

	public OrcFileWriter(String path, Class<T> clazz) throws IOException {
		this.path = path;
		this.clazz = clazz;

		writer = FileUtils.makeOrcWriter(path, clazz);
		file = new File(path);
	}

	@Override
	public void close() throws IOException {
		writer.close();
	}

	public <T> void addRow(T o) throws IOException {
		writer.addRow(o);
	}

	public <T> void addRow(List<T> list) throws IOException {
		for (T o : list) {
			writer.addRow(o);
		}
	}

	public void delete() throws IOException {
		file.delete();

		close();
	}
}

import java.io.File;
import java.io.IOException;

import org.apache.hadoop.hive.ql.io.orc.Reader;
import org.apache.hadoop.hive.ql.io.orc.RecordReader;

import lombok.Getter;

@Getter
public class OrcFileReader {
	private String path;
	private File file;

	private Reader reader;

	public OrcFileReader(String path) throws IOException {
		this.path = path;
		file = new File(path);

		reader = FileUtils.makeOrcReader(path);
	}

	public long count() {
		return reader.getNumberOfRows();
	}

	public void print() throws IOException {
		RecordReader rows = reader.rows();

		while (rows.hasNext()) {
			Object row = rows.next(null);
			System.out.println(row);
		}

		rows.close();
	}
}

https://orc.apache.org/docs/core-java.html

Using Core Java

https://www.javahelps.com/2020/08/read-and-write-orc-files-in-core-java.html

Read and Write ORC Files in Core Java