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how to copy only a part of .CSV based on first column elements with java

copy part like this(from date to date) I am trying to copy only a part of .CSV file based on the first column (Start Date and Time) data looks like (2019-01-28 10:22:00 AM) but the user have to put it like this (2019/01/28 10:22:00)
this is for windows, java opencsv , this is what I found but dont do what I need exaclty :
like this:
int startLine = get value1 from column csv ;
int endLine = get value2 from column csv;
public static void showLines(String fileName, int startLine, int endLine) throws IOException {
String line = null;
int currentLineNo = 1;
// int startLine = 20056;//40930;
// int currentLineNo = 0;
File currentDirectory = new File(new File(".").getAbsolutePath());
String fromPath = currentDirectory.getCanonicalPath() + "\\Target\\part.csv";
PrintWriter pw = null;
pw = new PrintWriter(new FileOutputStream(fromPath), true);
//pw.close();
BufferedReader in = null;
try {
in = new BufferedReader (new FileReader(fileName));
//read to startLine
while(currentLineNo<startLine) {
if (in.readLine()==null) {
// oops, early end of file
throw new IOException("File too small");
}
currentLineNo++;
}
//read until endLine
while(currentLineNo<=endLine) {
line = in.readLine();
if (line==null) {
// here, we'll forgive a short file
// note finally still cleans up
return;
}
System.out.println(line);
currentLineNo++;
pw.println(line);
}
} catch (IOException ex) {
System.out.println("Problem reading file.\n" + ex.getMessage());
}finally {
try { if (in!=null) in.close();
pw.close();
} catch(IOException ignore) {}
}
}
public static void main(String[] args) throws FileNotFoundException {
int startLine = 17 ;
int endLine = 2222;
File currentDirectory = new File(new File(".").getAbsolutePath());
try {
showLines(currentDirectory.getCanonicalPath() + "\\Sources\\concat.csv", startLine, endLine);
} catch (IOException e) {
e.printStackTrace();
}
// pw.println();
}

Common CSV format uses a comma as a delimiter, with quotations used to escape any column entry that uses them within the data. Assuming that your column one data is consistent with the format you posted, and that I wouldn't have to bother with quotations marks therefor, you could read the columns as:
public static void main(String[] args) {
//This is the path to the file you are writing to
String targetPath = "";
//This is the path to the file you are reading from
String inputFilePath = "";
String line = null;
ArrayList<String> lines = new ArrayList<String>();
boolean add = false;
String startLine = "2019/01/28 10:22:00";
String endLine = "2019/01/28 10:30:00";
String addFlagSplit[] = startLine.replace("/", "-").split(" ");
String addFlag = addFlagSplit[0] + " " + addFlagSplit[1];
String endFlagSplit[] = endLine.replace("/", "-").split(" ");
String endFlag = endFlagSplit[0] + " " + endFlagSplit[1];
try(PrintWriter pw = new PrintWriter(new FileOutputStream(targetPath), true)){
try (BufferedReader input = new BufferedReader(new FileReader(inputFilePath))){
while((line = input.readLine()) != null) {
String date = line.split(",")[0];
if(date.contains(addFlag)) {
add = true;
}else if(date.contains(endFlag)) {
break;
}
if(add) {
lines.add(line);
}
}
}
for(String currentLine : lines) {
pw.append(currentLine + "\n");
}
}catch(FileNotFoundException e) {
e.printStackTrace();
}catch(IOException e) {
e.printStackTrace();
}catch(Exception e) {
e.printStackTrace();
}
}

public static void main(String[] args) throws IOException {
File currentDirectory = new File(new File(".").getAbsolutePath());
String targetPath = currentDirectory.getCanonicalPath() + "\\Target\\part.csv";
String inputFilePath = currentDirectory.getCanonicalPath() + "\\Sources\\concat.csv";
String line = null;
ArrayList<String> lines = new ArrayList<String>();
boolean add = false;
String startLine = "2019/01/28 10:22:00";
String endLine = "2019/04/06 10:30:00";
try(PrintWriter pw = new PrintWriter(new FileOutputStream(targetPath), true)){
try (BufferedReader input = new BufferedReader(new FileReader(inputFilePath))){
while((line = input.readLine()) != null) {
String date = line.split(",")[0];
if(date.contains(startLine)) {
add = true;
}else if(date.contains(endLine)) {
break;
}
if(add) {
lines.add(line);
}
}
}
for(String currentLine : lines) {
pw.append(currentLine + "\n");
}
}catch(FileNotFoundException e) {
e.printStackTrace();
}catch(IOException e) {
e.printStackTrace();
}catch(Exception e) {
e.printStackTrace();
}
}

Parsing strings with split JAVA

I'm trying to find an object in a list from a text file
Example:
L;10;€10,50;83259875;YellowPaint
-H;U;30;€12,00;98123742;Hammer
G;U;80;€15,00;87589302;Seeds
By inserting 98123742 by input with scanner, i want to find that string.
I tried to do this:
private static void inputCode() throws IOException {
String code;
String line = null;
boolean retVal = false;
System.out.println("\ninsert code: ");
code = in.next();
try {
FileReader fileReader = new FileReader("SHOP.txt");
BufferedReader bufferedReader = new BufferedReader(fileReader);
while ((line = bufferedReader.readLine()) != null) {
String[] token = line.split(";");
if (token[0].equals(code) && token[1].equals(code)) {
retVal = true;
System.out.println(line);
}
}
bufferedReader.close();
} catch (FileNotFoundException ex) {
System.out.println("impossible open the file " + fileName);
}
catch(IOException ex) {
System.out.println(
"Error reading file '"
+ fileName + "'");
}
System.out.println(retVal);
}
How can i print "-H;U;30;€12,00;98123742;Hammer" inserting "98123742" (that is the code of the product) ?

Why are you splitting in the first place? For such a simple usecase, and with that line format, I'd go with
line.contains(";" + code);
Not much else to do.

Debugging File Search / Merge Code

This program is meant to see two files located in a particular folder and then merge those two files and create a third file which is does. From the third merged file it is then searching for a keyword such as "test", once it finds that key word it prints out the location and the line of the keyword which is what is somewhat doing. What is happening is when I run the program it stops after the finds the keyword the first time in a line but it will not continue to search that line. So if there is multiple keyword 'test' in the line it will only find the first one and spit back the position and line. I want it to print both or multiple keywords. I think it is because of the IndexOf logic which is causing the issue.
import com.sun.deploy.util.StringUtils;
import java.io.*;
import java.lang.*;
import java.util.Scanner;
public class Concatenate {
public static void main(String[] args) {
String sourceFile1Path = "C:/Users/me/Desktop/test1.txt";
String sourceFile2Path = "C:/Users/me/Desktop/test2.txt";
String mergedFilePath = "C:/Users/me/Desktop/merged.txt";
File[] files = new File[2];
files[0] = new File(sourceFile1Path);
files[1] = new File(sourceFile2Path);
File mergedFile = new File(mergedFilePath);
mergeFiles(files, mergedFile);
stringSearch(args);
}
private static void mergeFiles(File[] files, File mergedFile) {
FileWriter fstream = null;
BufferedWriter out = null;
try {
fstream = new FileWriter(mergedFile, true);
out = new BufferedWriter(fstream);
} catch (IOException e1) {
e1.printStackTrace();
}
for (File f : files) {
System.out.println("merging: " + f.getName());
FileInputStream fis;
try {
fis = new FileInputStream(f);
BufferedReader in = new BufferedReader(new InputStreamReader(fis));
String aLine;
while ((aLine = in.readLine()) != null) {
out.write(aLine);
out.newLine();
}
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
try {
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private static void stringSearch(String args[]) {
try {
String stringSearch = "test";
BufferedReader bf = new BufferedReader(new FileReader("C:/Users/me/Desktop/merged.txt"));
int linecount = 0;
String line;
System.out.println("Searching for " + stringSearch + " in file");
while (( line = bf.readLine()) != null){
linecount++;
int indexfound = line.indexOf(stringSearch);
if (indexfound > -1) {
System.out.println(stringSearch + " was found at position " + indexfound + " on line " + linecount);
System.out.println(line);
}
}
bf.close();
}
catch (IOException e) {
System.out.println("IO Error Occurred: " + e.toString());
}
}
}

It's because you are searching for the word once per line in your while loop. Each iteration of the loop takes you to the next line of the file because you are calling bf.readLine(). Try something like the following. You may have to tweak it but this should get you close.
while (( line = bf.readLine()) != null){
linecount++;
int indexfound = line.indexOf(stringSearch);
while(indexfound > -1)
{
System.out.println(stringSearch + " was found at position " + indexfound + " on line " + linecount);
System.out.println(line);
indexfound = line.indexOf(stringSearch, indexfound);
}
}

Java : Can't capture console output of a console program (Blockland.exe)

I'm trying to capture the output of a console program and write overwriting lines of the output to a file which another program will read, line by line I write into this file (the file should only contain one line at a time) but when I made this code and tried running it, it didn't work. The process started perfectly, but the file is not being created, written to, and I am not getting any System.out.println's of "Streaming : blah blah blah"
You can read the code below or use this pastebin : http://pastebin.com/raw.php?i=Yahsqxma
import java.io.*;
import java.util.Scanner;
public class OpenRC {
static BufferedReader consoleInput = null;
static String os = System.getProperty("os.name").toLowerCase();
static Process server;
public static void main(String[] args) throws IOException {
// OpenRC by Pacnet2013
System.out.println(System.getProperty("user.dir"));
if(os.indexOf("win") >= 0) {
os = "Windows";
}
else if(os.indexOf("mac") >= 0) {
os = "Mac";
}
else if(os.indexOf("nux") >= 0) {
os = "Linux";
}
switch(os){
case "Linux" : //cause I need WINE
File file = new File(System.getProperty("user.dir") + "/OpenRC.txt");
try {
Scanner scanner = new Scanner(file);
String path = scanner.nextLine();
System.out.println("Got BlocklandEXE - " + path);
String port = scanner.nextLine();
System.out.println("Got port - " + port);
scanner.close();
server = new ProcessBuilder("wine", path + "Blockland.exe", "ptlaaxobimwroe", "-dedicated", "-port" + port).start();
if(consoleInput != null)
consoleInput.close();
consoleInput = new BufferedReader(new InputStreamReader(server.getInputStream()));
streamLoop();
} catch (FileNotFoundException e) {
System.out.println("You don't have an OpenRC Config file OpenRC.txt in the directory of this program");
}
}
}
public static void streamConsole()
{
String line = "";
int numLines = 0;
try
{
if (consoleInput != null)
{
while((line = consoleInput.readLine()) != null && consoleInput.ready())
{
numLines++;
}
}
}
catch (IOException e)
{
System.out.println("There may be a problem - An IOException (java.io.IOException) was caught so some lines may not display / display correctly");
}
if(!line.equals("") && !(line == null))
{
System.out.println("Streaming" + numLines + line);
writeToFile(System.getProperty("user.dir"), line);
}
}
public static void streamLoop()
{
try
{
Thread.sleep(5000);
}
catch (InterruptedException e)
{
System.out.println("A slight problem may have happened while trying to read a command");
}
streamConsole();
streamLoop(); //it'll go on until you close this program
}
public static void writeToFile(String filePath, String content)
{
try {
File file = new File(filePath);
if (!file.exists()) {
file.createNewFile();
System.out.println("Creating new stream text file");
}
FileWriter writer = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(writer);
bw.write(content);
bw.close();
System.out.println("Wrote stream text file");
} catch (IOException e) {
e.printStackTrace();
}
}
}

You are running a DOS console application, which does not necessarily write to stdout or stderr, but it writes to the "console". It's nearly impossible to capture the "console" output reliably. The only tool that I have ever seen that is able to capture console output is expect by Don Libes, and that does all sorts of hacks.

Splitting a Byte Array on A Particular Byte

I am trying to read an old .dat file byte by byte, and have run into an issue: a record is terminated by \n (newline). I'd like to read in the whole byte array, then split it on the character.
I can do this by reading the whole byte array from the file, creating a String with the contents of the byte array, then calling String.split(), but find this to be inefficient. I'd rather split the byte array directly if possible.
Can anyone assist?
Update: Code was requested.
public class NgcReader {
public static void main(String[] args) {
String location;
if (System.getProperty("os.name").contains("Windows")) {
location = "F:\\Programming\\Projects\\readngc\\src\\main\\java\\ngcreader\\catalog.dat";
} else {
location = "/media/My Passport/Programming/Projects/readngc/src/main/java/ngcreader/catalog.dat";
}
File file = new File(location);
InputStream is = null;
try {
is = new FileInputStream(file);
} catch (FileNotFoundException e) {
System.out.println("It didn't work!");
System.exit(0);
}
byte[] fileByteArray = new byte[(int) file.length() - 1];
try {
is.read(fileByteArray);
is.close();
} catch (IOException e) {
System.out.println("IOException!");
System.exit(0);
}
// I do NOT like this. I'd rather split the byte array on the \n character
String bigString = new String(fileByteArray);
List<String> stringList = Arrays.asList(bigString.split("\\n"));
for (String record : stringList) {
System.out.print("Catalog number: " + record.substring(1, 6));
System.out.print(" Catalog type: " + record.substring(7, 9));
System.out.print(" Right Ascension: " + record.substring(10, 12) + "h " + record.substring(13, 17) + "min");
System.out.print(" Declination: " + record.substring(18, 21) + " " + record.substring(22, 24));
if (record.length() > 50) {
System.out.print(" Magnitude: " + record.substring(47, 51));
}
if (record.length() > 93) {
System.out.print(" Original Notes: " + record.substring(54,93));
}
if (record.length() > 150) {
System.out.print(" Palomar Notes: " + record.substring(95,150));
}
if (record.length() > 151) {
System.out.print(" Notes: " + record.substring(152));
}
System.out.println();
}
}
Another Update: Here's a README with a description of the file I'm processing:
http://cdsarc.u-strasbg.fr/viz-bin/Cat?VII/1B

It sounds like this might actually just be a text file to start with, in which case:
InputStream stream = new FileInputStream(location);
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(stream,
"ASCII"));
String line;
while ((line = reader.readLine()) != null) {
// Handle the line, ideally in a separate method
}
} finally {
stream.close();
}
This way you never need to have more than a single line of the file in memory at a time.

if you're set on using byte arrays...
byte[] buff = new byte[1024];//smaller buffer
try {
int ind=0,from=0,read;
while((read=is.read(buff,ind,buff.length-ind))!=-1){
for(int i=ind;i<ind+read;i++){
if(buff[i]=='\n'){
string record = new String(buff,from,i+1);
//handle
from=i+1;
}
}
System.arraycopy(buff,from,buff,0,buff.length-from);
ind=ind+read-from;
from=0;
}
} catch (IOException e) {
System.out.println("IOException!");
//System.exit(0);
throw RunTimeException(e);//cleaner way to die
} finally{
is.close();
}
this also avoids loading in the entire file and it puts the close inside a finally