Draft of Java code to save NSE Historical Data in file System instead of Database, Just For TRY! Not yet tested at all

package entitity;

import java.io.EOFException;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.io.Serializable;

import java.nio.file.Files;

import java.nio.file.Paths;

import java.time.LocalDate;

import java.time.format.DateTimeFormatter;

import java.util.HashMap;

import java.util.HashSet;

import java.util.stream.Stream;

public class HD implements Serializable {

public static void main(String args[]) {

String csvFilePath = "D:\\nseEquityHistoricalDataCsv\\20200116\\"

+ "Quote-Equity-INFRATEL-EQ-14-03-2020-to-14-06-2020.csv";

String dbPath = "D:\\javaWebServers\\ApacheTomEE\\nseeq\\";

String hdTablePath = dbPath + "hd.tb", hdLogPath = dbPath + "hd.lg";

try (Stream<String> stream1 = Files.lines(Paths.get(csvFilePath));

Stream<String> stream2 = Files.lines(Paths.get(csvFilePath))) {

String[] headerLineArr = stream1.findFirst().get().toString().replaceAll("\"", "").split(",");

for (Integer i = 0; i < headerLineArr.length; i++) {

headerLineArr[i] = headerLineArr[i].trim();

}

stream2.skip(1).forEach(e -> {

HD hd = new HD("INFRATEL", headerLineArr, e.replaceAll("\"", ""));

System.out.println(hd.toString());

});

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

LocalDate d;

String s;

String series;

Double pc, o, h, l, ltp, c;

Long v;

Double turnover;

Double _52WH, _52WL;

Long noOfTrades;

Boolean delFlag = false;

private static final DateTimeFormatter dft = DateTimeFormatter.ofPattern("dd-MMM-yyyy");

private static final Integer logFileHeapSize = 512;

public HD(String s, String[] headerLineArr, String line) {

String[] lineArr = line.replaceAll("\"\"", "").split(",");

HashMap<String, String> row = new HashMap<String, String>();

for (Integer i = 0; i < headerLineArr.length; i++) {

row.put(headerLineArr[i], lineArr[i].trim());

}

// this.d=LocalDate.parse(row.get("Date"),dft);

this.d = LocalDate.parse(lineArr[0], dft);

this.s = s;

this.series = row.get("series");

this.pc = Double.valueOf(row.get("PREV. CLOSE"));

this.o = Double.valueOf(row.get("OPEN"));

this.h = Double.valueOf(row.get("HIGH"));

this.l = Double.valueOf(row.get("LOW"));

this.ltp = Double.valueOf(row.get("ltp"));

this.c = Double.valueOf(row.get("close"));

this.v = Long.valueOf(row.get("VOLUME"));

this.turnover = Double.valueOf(row.get("VALUE"));

this._52WH = Double.valueOf(row.get("52W H"));

this._52WL = Double.valueOf(row.get("52W L"));

this.noOfTrades = Long.valueOf(row.get("No of trades"));

}

    

        //default constructor and other constructers omitted for brevity

// getters and setters omitted for brevity

@Override

public int hashCode() {

final int prime = 31;

int result = 1;

result = prime * result + ((d == null) ? 0 : d.hashCode());

result = prime * result + ((s == null) ? 0 : s.hashCode());

result = prime * result + ((series == null) ? 0 : series.hashCode());

return result;

}

@Override

public boolean equals(Object obj) {

if (this == obj)

return true;

if (obj == null)

return false;

if (getClass() != obj.getClass())

return false;

HD other = (HD) obj;

if (d == null) {

if (other.d != null)

return false;

} else if (!d.equals(other.d))

return false;

if (s == null) {

if (other.s != null)

return false;

} else if (!s.equals(other.s))

return false;

if (series == null) {

if (other.series != null)

return false;

} else if (!series.equals(other.series))

return false;

return true;

}

@Override

public String toString() {

// omitted for brevity

}

public static void deFragmentTable(String filePath) throws IOException, ClassNotFoundException {

// set names of logFile and tmp file

String logFilePath = filePath.substring(0, filePath.length() - 2) + "lg";

if (Files.size(Paths.get(logFilePath)) < logFileHeapSize * 1000000) {

return;

}

String tmpPath = filePath.subSequence(0, filePath.length() - 2) + "tmp";

// read form tb file in a set

FileInputStream fis = new FileInputStream(filePath);

ObjectInputStream ois = new ObjectInputStream(fis);

HashSet<HD> set = (HashSet<HD>) ois.readObject();

ois.close();

// update set from log file to latest values

ois = new ObjectInputStream(new FileInputStream(logFilePath));

while (true) {

try {

HD obj = (HD) ois.readObject();

set.remove(obj);

set.add(obj);

} catch (EOFException e) {

break;

}

}

// write set to tmp file

File fileTmp = new File(tmpPath, "w");

fileTmp.createNewFile();

try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(fileTmp))) {

oos.writeObject(set);

}

// deletes old table file and log file, them rename tmp file to table file

Files.delete(Paths.get(filePath));

Files.delete(Paths.get(logFilePath));

new File(tmpPath).renameTo(new File(filePath));

}

public static void insert(String filePath, HD obj) throws Exception {

HD prevObj = getLatestPrevObject(filePath, obj);

// if object don't exists in filePath, write object in file path

if (prevObj==null) {

writeObjectInFilePath(filePath, prevObj);

} else {

// if object in deleated status in logPath, write object in logPath

if (prevObj.getDelFlag()) {

writeObjectInLogPath(filePath, prevObj);

} else {

// if object not in deleated status in filePath, throw onject already exists

// exception

throw new Exception("Object already exists");

}

}

}

public static void update(String filePath, HD obj) throws Exception {

HD prevObj = getLatestPrevObject(filePath, obj);

// if object exists and not in deleated state

if(prevObj!=null && !prevObj.getDelFlag()) {

writeObjectInLogPath(filePath, prevObj);

}else {

// throw object not exists exception

throw new Exception("object not available for update as it don't exists");

}

}

public static void delete(String filePath,HD obj) throws Exception {

HD prevObj = getLatestPrevObject(filePath, obj);

// if object exists and not in deleated state

if(prevObj!=null && !prevObj.getDelFlag()) {

prevObj.setDelFlag(true);

writeObjectInLogPath(filePath, prevObj);

}else {

// throw object not exists exception

throw new Exception("object not available for deletion as it don't exists");

}

}

public static HD findObjectInFilePath(String filePath, HD obj) throws IOException, ClassNotFoundException {

HD prevObj = null;

// check if object already exists in filePath

Boolean objectFoundInFilePath = false;

File file = new File(filePath);

file.createNewFile();

ObjectInputStream isFilePath = new ObjectInputStream(new FileInputStream(file));

while (!objectFoundInFilePath) {

try {

HD obj2 = (HD) isFilePath.readObject();

if (obj.equals(obj2)) {

prevObj = obj2;

objectFoundInFilePath = true;

}

} catch (EOFException e) {

break;

}

}

isFilePath.close();

return prevObj;

}

public static void updateLatestObjectInLogPath(String filePath, HD prevObj)

throws IOException, ClassNotFoundException {

// if object exists in filePath, get this final object in logPath

String logFilePath = filePath.substring(0, filePath.length() - 2) + "lg";

File logFile = new File(logFilePath);

logFile.createNewFile();

ObjectInputStream isLogPath = new ObjectInputStream(new FileInputStream(logFilePath));

while (true) {

try {

HD obj2 = (HD) isLogPath.readObject();

if (prevObj.equals(obj2)) {

prevObj = obj2;

}

} catch (EOFException e) {

break;

}

}

isLogPath.close();

}

public static HD getLatestPrevObject(String filePath, HD obj) throws ClassNotFoundException, IOException {

HD prevObj = findObjectInFilePath(filePath, obj);

if (prevObj == null) {

return null;

} else {

updateLatestObjectInLogPath(filePath, prevObj);

return prevObj;

}

}

public static void writeObjectInFilePath(String filePath,HD obj) throws FileNotFoundException, IOException {

File file=new File(filePath);

ObjectOutputStream osFilePath = new ObjectOutputStream(new FileOutputStream(file));

osFilePath.writeObject(obj);

osFilePath.close();

}

public static void writeObjectInLogPath(String filePath,HD obj) throws IOException, ClassNotFoundException {

String logFilePath = filePath.substring(0, filePath.length() - 2) + "lg";

ObjectOutputStream osLogPath = new ObjectOutputStream(new FileOutputStream(logFilePath));

osLogPath.writeObject(obj);

osLogPath.close();

deFragmentTable(filePath);

}

}