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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.

Java - Trying to output to a file where if the user's login is there only replace the balance

My program is basically a user's name, and balance, this is stored in a file, when the user updates their profile, I want their balance to update too, but not their name, as they already have it in the file.
The name and balance are split with a comma. In the file it is displayed like this:
Stacey,0.02
(The name is actually a randomly generated number+letter string, but I thought I'd keep it simple here.)
When I try to write to the file with this code, it doesn't write anything.
Code:
btnSaveUserid.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String text = txtUserid.getText().toString();
String balance = beedcoin1Balance.getText().toString();
File file = new File("d:/users/joel/desktop/code/usersid.txt");
BufferedReader br = null;
try {
String sCurrentLine;
br = new BufferedReader(new FileReader("d:/users/joel/desktop/code/usersid.txt"));
List<String> terms = new ArrayList<String>();
List<String> ttlBalance = new ArrayList<String>();
while ((sCurrentLine = br.readLine()) != null) {
String[] ar = sCurrentLine.split(",");
String userid = ar[0];
terms.add(userid);
System.out.println(terms);
}
if(terms.contains(text)) {
PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("d:/users/joel/desktop/code/usersid.txt")));
Scanner scanner = new Scanner(file);
while(scanner.hasNextLine());
String line = scanner.nextLine();
String[] ar = line.split(",");
String userid = ar[0];
String bdcv1val = ar[1];
int lineNum = 0;
lineNum++;
if(line.equals(userid)) {
Path path = Paths.get("d:/users/joel/desktop/code/usersid.txt");
Charset charset = StandardCharsets.UTF_8;
String content = new String(Files.readAllBytes(path), charset);
content = content.replace(txtUserid.toString(), txtUserid.toString());
Files.write(path, content.getBytes(charset));
out.println(text + "," + balance);
System.out.println("Successfully printed to usersid.txt");
}
}
else {
PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("d:/users/joel/desktop/code/usersid.txt")));
out.println(text + "," + balance);
System.out.println("Successfully printed to usersid.txt");
}
} catch (IOException el) {
el.printStackTrace();
} finally {
try {
if(br != null)br.close();
} catch (IOException ex) {
ex.printStackTrace();
}
}
It all takes place in a button's action listener, and this code outputs the "Successfully printed to file" but doesn't actually print it to the file. I'm honestly perplexed, any help would be greatly appreciated.

Need to parse a string so each individual element can be compared to an element in another string

I am trying to parse the text from a file that reads "This is a test. This is a simple test." I need to parse it so I can compare it to another file which is a dictionary. This is apart of a spell check program. I am having troubles implementing a r.readline and r.split methods.
String fileName2 = "test.txt";
String line2 = null;
String[] diction2 = new String [100];
try {
// FileReader reads text files in the default encoding.
FileReader fileReader2 =
new FileReader(fileName2);
// Always wrap FileReader in BufferedReader.
BufferedReader bufferedReader2 =
new BufferedReader(fileReader2);
int j=0;
while((line = bufferedReader2.readLine()) != null) {
//System.out.println(line);
diction2[j]=line;
System.out.println(diction2[j]);
j++;
//r.readline(line);
//delimiter
//r.split
//need to parse line to get each individual word out and compare to dictionary
}
// Always close files.
bufferedReader2.close();
}
catch(FileNotFoundException ex) {
System.out.println(
"Unable to open file '" +
fileName + "'");
}
catch(IOException ex) {
System.out.println(
"Error reading file '"
+ fileName + "'");
// Or we could just do this:
// ex.printStackTrace();
}

Edit:
when you do:
for(String word : words){
//Do some action
}
it means that it will take each string inside the "words" array, one by one, store it inside "word" and execute the "Do some action" for it.
it is the same as writing:
for(int i = 0; i < words.length; i++){
String word = words[i];
//Do something
}
End of edit.
As here:
while((line = bufferedReader2.readLine()) != null) {
You are already reading the line, can't you just do:
String fileName2 = "test.txt";
String line = null;
String[] diction2 = new String [100];
try {
// FileReader reads text files in the default encoding.
FileReader fileReader2 =
new FileReader(fileName2);
// Always wrap FileReader in BufferedReader.
BufferedReader bufferedReader2 =
new BufferedReader(fileReader2);
int j=0;
while((line = bufferedReader2.readLine()) != null) {
//System.out.println(line);
diction2[j]=line;
System.out.println(diction2[j]);
j++;
//There you get the list of all the words in the line
String[] words = line.split(" ");
for(String word : words){
//Check your word here
}
}
// Always close files.
bufferedReader2.close();
}
catch(FileNotFoundException ex) {
System.out.println(
"Unable to open file '" +
fileName + "'");
}
catch(IOException ex) {
System.out.println(
"Error reading file '"
+ fileName + "'");
// Or we could just do this:
// ex.printStackTrace();
}

print a line that contains a specific pattern from a text-file in java

public class Auto
{
public static void main(String [] args) {
// The name of the file to open.
System.out.print("\nPlease enter TextfileName.txt : ");
Scanner keyboard = new Scanner(System.in);
String fileName = keyboard.next();
int counter = 0;
//Reading filename.text from code
System.out.println("\nReading '"+fileName+"' from Java Code.\n");
//Date and time stamp for the program.
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Date date = new Date();
System.out.print("Todays date: "+dateFormat.format(date)+"\n\n\n");
// This will reference one line at a time
String line = null;
FileReader fileReader = null;
//-------------------------------------------------------TAB_1----------------------------------------------//
System.out.println("\t\t\t\t TAB_1[Date on]\n");
try {
// FileReader reads text files in the default encoding.
fileReader = new FileReader(fileName);
// Always wrap FileReader in BufferedReader.
BufferedReader bufferedReader = new BufferedReader(fileReader);
while((line = bufferedReader.readLine()) != null) {
counter++;
if(counter == 1 || counter == 3 || counter == 9)
{
// print out the lines above that are found in the text
System.out.println(line);
System.out.println("----------");
}
}
}
catch(FileNotFoundException ex) {
System.out.println("Unable to open file '" + fileName + "'");
}
catch(IOException ex) {
System.out.println("Error reading file '" + fileName + "'");
// Or we could just do this:
// ex.printStackTrace();
}
finally
{
if(fileReader != null){
// Always close files.
// BufferedReader.close();
}
}
some matcher would help, but i`m not sure how it works
}}
The one i have above is working but i want to also find a specific string anywhere in the text-file and print that line

Just use the contains method of the String class to check for occurances of a substring inside a string.
while((line = bufferedReader.readLine()) != null) {
if (line.contains("some string") {
System.out.println(line);
System.out.println("----------");
}
}
If you wish to check multiple substrings and not just one then you should create a String array of all the substrings you want to look for and loop through them.
First add the following line at the beggining of the class :
public static final String[] listOfStrings = new String[] { "substring 0", "sub string 1" , "substring 2" };
Replace the substrings with your own values.
Then, loop through them to find matches:
while((line = bufferedReader.readLine()) != null) {
for (String match : listOfStrings) {
if (line.contains(match)) {
System.out.println(line);
System.out.println("----------");
break; // No need to continue after the first match
}
}
}

Java Exception Handling with Try in a method

I am trying to design two different methods for a Java application. The first method will pass in a string of the name of a file, and return the text of a text file as a string. The second method will pass in the name of a file and the text, and create a new text file and output the string into the file.
Currently my code works without the methods, but I am trying to design it with a separation of concerns and low coupling. I am trying to modify it so I can just call a method to output any sort of data I have in a string to a text file.
Here is my code without the methods:
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.*;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;
public class FileCopier {
public static void main(String[] args) {
//What file should be input for reading?
String inputFile = askForInput("Please enter the name of the file to be read in: ");
//What file should be created to display output ?
String outputFile = askForInput("Please come up with a name of the file to be written backwards: ");
//Check to make sure we got the names
System.out.println("inputFile: " + inputFile + " outputFile: " + outputFile);
// Variables to read and write the files
//Call the readTextFile method to read text file into string data
String line = null;
String total = null;
BufferedReader input = null;
try {
// FileReader reads text files in the default encoding.
FileReader fileReader = new FileReader(inputFile);
// Always wrap FileReader in BufferedReader.
input = new BufferedReader(fileReader);
total = input.readLine() + "\n";
while ((line = input.readLine()) != null && total != null) {
total += line + "\n";
System.out.println("Proof that the file says: " + line);
}
input.close();
//Check to make sure we got the text files data
System.out.println("The total string says: \n" + total);
//Call the reverseWords method to switch 'Hello' with 'World'
String info = reverseWords(total);
//Check to make sure the string was reversed
System.out.println("The reversed string says: \n" + info);
File file = new File(outputFile);
BufferedWriter output = null;
output = new BufferedWriter(new FileWriter(file));
output.write(info);
System.out.println("The output file: " + outputFile + " has been written.");
output.close();
} catch (FileNotFoundException ex) {
System.out.println("Unable to open file '" +
inputFile + "'");
} catch (IOException ex) {
System.out.println("Error reading file '" + inputFile + "'");
// Or we could just do this:
// ex.printStackTrace();
}
}
public static String reverseWords(String sentence) {
String[] parts = sentence.trim().split("\\s+");
StringBuilder builder = new StringBuilder();
builder.append(parts[parts.length - 1]);
for (int i = parts.length - 2; i >= 0; --i) {
builder.append(" ").append(parts[i]);
}
return builder.toString();
}
public static String askForInput(String question) {
System.out.println(question);
Scanner in = new Scanner(System.in);
String inputFile = in.nextLine();
return inputFile;
}
}
When creating a method for each of the "read" and "write" portions of my code, I constantly get errors that I assume are from the exception handling. Any thoughts on how to separate code that has exceptions involved?

Think in terms of single responsibility. You have two distinct operations that need to happen: reading and writing.
Let's start with reading. What you're doing right now to read the file surmises these lines:
// FileReader reads text files in the default encoding.
FileReader fileReader = new FileReader(inputFile);
// Always wrap FileReader in BufferedReader.
input = new BufferedReader(fileReader);
total = input.readLine() + "\n";
while ((line = input.readLine()) != null && total != null) {
total += line + "\n";
System.out.println("Proof that the file says: " + line);
}
input.close();
Move that to a method.
private static String readFile(String inputFile) throws IOException {
BufferedReader input;
String total;
String line;// FileReader reads text files in the default encoding.
FileReader fileReader = new FileReader(inputFile);
// Always wrap FileReader in BufferedReader.
input = new BufferedReader(fileReader);
total = input.readLine() + "\n";
while ((line = input.readLine()) != null) {
total += line + "\n";
System.out.println("Proof that the file says: " + line);
}
input.close();
return total;
}
Here's what we did:
We have a variable total which is used elsewhere in the program, so that usage has to be preserved. We're returning String and will declare total = readFile(inputFile); on the outside.
We've changed nothing. This code will run the same way as it did without the method.
Now, if we want to move the writing functionality, which is:
File file = new File(outputFile);
BufferedWriter output = null;
output = new BufferedWriter(new FileWriter(file));
output.write(info);
System.out.println("The output file: " + outputFile + " has been written.");
output.close();
...we just do.
private static void writeFile(String outputFile, String info) throws IOException {
File file = new File(outputFile);
BufferedWriter output = null;
output = new BufferedWriter(new FileWriter(file));
output.write(info);
System.out.println("The output file: " + outputFile + " has been written.");
output.close();
}
Again, nothing's changed on this method. We don't have any other usages of any of the variables in here to worry about, so we can directly bring it across.
All said, that try block looks a bit anemic:
try {
total = readFile(inputFile);
//Check to make sure we got the text files data
System.out.println("The total string says: \n" + total);
//Call the reverseWords method to switch 'Hello' with 'World'
String info = reverseWords(total);
//Check to make sure the string was reversed
System.out.println("The reversed string says: \n" + info);
writeFile(outputFile, info);
} catch (FileNotFoundException ex) {
System.out.println("Unable to open file '" +
inputFile + "'");
} catch (IOException ex) {
System.out.println("Error reading file '" + inputFile + "'");
// Or we could just do this:
// ex.printStackTrace();
}
...which is a good thing.

I am not sure what are you asking about but try to create your own Exceptions and make your methods throw them like this
package com.qmic.test;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.*;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;
public class FileCopier {
public static void main(String[] args) {
// What file should be input for reading?
String inputFile = askForInput("Please enter the name of the file to be read in: ");
// What file should be created to display output ?
String outputFile = askForInput("Please come up with a name of the file to be written backwards: ");
// Check to make sure we got the names
System.out.println("inputFile: " + inputFile + " outputFile: "
+ outputFile);
// Variables to read and write the files
// Call the readTextFile method to read text file into string data
String line = null;
String total = null;
BufferedReader input = null;
try {
String readData = readFileContents(inputFile);
// Check to make sure we got the text files data
System.out.println("The total string says: \n" + readData);
// Call the reverseWords method to switch 'Hello' with 'World'
String reversedContents = reverseWords(readData);
writeToFile(outputFile, reversedContents);
} catch (ReadException ex) {
System.out.println("Error reading file '" + inputFile + "'");
// Or we could just do this:
// ex.printStackTrace();
} catch (WriteException ex) {
System.out.println("Error Writing file '" + outputFile + "'");
// Or we could just do this:
// ex.printStackTrace();
}
}
public static String reverseWords(String sentence) {
String[] parts = sentence.trim().split("\\s+");
StringBuilder builder = new StringBuilder();
builder.append(parts[parts.length - 1]);
for (int i = parts.length - 2; i >= 0; --i) {
builder.append(" ").append(parts[i]);
}
return builder.toString();
}
public static String askForInput(String question) {
System.out.println(question);
Scanner in = new Scanner(System.in);
String inputFile = in.nextLine();
return inputFile;
}
public static void writeToFile(String fileName, String data)
throws WriteException {
BufferedWriter output = null;
try {
// Check to make sure the string was reversed
System.out.println("The reversed string says: \n" + data);
File file = new File(fileName);
output = new BufferedWriter(new FileWriter(file));
output.write(data);
System.out.println("The output file: " + fileName
+ " has been written.");
}catch(IOException e){
throw new WriteException();
}finally{
try {
output.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public static String readFileContents(String fileName) throws ReadException {
// FileReader reads text files in the default encoding.
BufferedReader input = null;
String line = null;
String total = null;
try {
FileReader fileReader = new FileReader(fileName);
// Always wrap FileReader in BufferedReader.
input = new BufferedReader(fileReader);
total = input.readLine() + "\n";
while ((line = input.readLine()) != null && total != null) {
total += line + "\n";
System.out.println("Proof that the file says: " + line);
}
} catch (IOException e) {
throw new ReadException();
}finally{
//This is ugly code, if you are using java 7 you have extra option to better this
try {
input.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return total;
}
}
//make me public and move me to a separate file
class WriteException extends IOException {
}
//make me public and move me to a separate file
class ReadException extends IOException {
}