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Retrieving variables from a text file through a hashmap

I am creating a school program for a project in which I a writing words and translations to a file, (separated by a character). I have read that I can read them via a hash map into an array. I was just wondering if someone could point me in the right direction as how to do this.
If anyone has a better idea of how to store and retrieve the words I would love to learn. The reason I am writing to a file is so the user can store as many words as they want.
Thank-you so much :D

You can use java.util.HashMap to store user words and related translations:
String userWord = null;
String translation = null, translation1 = null;
Map<String, String[]> map = new HashMap();
map.put(userWord, new String[] { translation, translation1 });
String[] translations = map.get(userWord);
This map lets you map single userWord to multiple translations.

Here's a reference for learning how to use BufferedReader: BufferedReader
Here's a reference for learning how to use FileReader: FileReader
import java.io.*;
class YourClass
{
public static void main() throws IOException
{
File f = new File("FilePath"); // Replace every '\' with '/' in the file path
FileReader fr = new FileReader(f);
BufferedReader br = new BufferedReader(fr);
String line = "";
String FileString = "";
while((line = br.readLine()) != null)
{
// Now 'line' contains each line of the file
// If you want, you can store the entire file in a String, like this:
FileString += line + "\n"; // '\n' to register each new line
}
System.out.println(FileString);
}
} // End of class
I'm still a newbie, and don't understand much about HashMap, but I can tell you how to store it in a String array:
FileString = FileString.replaceAll("\\s+", " ");
String[] Words = FileString.split(" ");
FileString.replaceAll("\\s+", " ") - Replaces 1 or more spaces with 1 space, so as to avoid any logical errors.
FileString.split(" ") - Returns a String array of each String separated by a space.

You can try something like this
File f = new File("/Desktop/Codes/Text.txt");
// enter your file location
HashMap<String, String[]> hs = new HashMap<String, String[]>();
// throw exception in main method
Scanner sc = new Scanner(f);
String s="";
while(sc.hasNext()){
s = sc.next();
// create a method to search translation
String []trans = searchTrans(s);
hs.put(s, trans);
}

How to read a multiple String values from text line and store them to a String variable(java)

I want to read line by line from a text file in java, one line consist of 4 fields but one field can contain multiple words, For Ex.:
I have this line: Screen Commercial Problem with product
How can I store this three fields of my line into 3 String variables in java?
var1 -> "Screen"
var2 -> "Commercial"
var3 -> "Problem with product"

This splits the input. Use System.in instead of inputStream if reading from standard input:
BufferedReader in = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = in.readLine()) != null) {
String[] split = line.split(" ", 3);
String var1 = split[0]; String var2 = split[1]; String var3 = split[2];
// do whatever is needed...
}

Ideally, you'll want to use some specific character to indicate the breaks between fields. For example, Screen|Commercial|Problem with product. Then you could write code that reads the entire line as input and then divides it into substrings. For example:
File yourFile = new File(/*file path goes here*/);
Scanner sc = new Scanner(yourFile);
String input;
String var1;
String var2;
String var3;
int breakIndex;
while (sc.hasNextLine()) {
input = sc.nextLine();
breakIndex = input.indexOf("|");
var1 = input.substring(0, breakIndex);
input = input.substring(breakIndex+1);
breakIndex = input.indexOf("|");
var2 = input.substring(0, breakIndex);
var3 = input.substring(breakIndex+1);
// do whatever it is you plan to do with those variables here
}

Retrieving part of a string using a delimiter

Okay So I am creating an application but I'm not sure how to get certain parts of the string. I have read In a file as such:
*tp*|21394398437984|163600
*2*|AAA|1234567894561236|STOP|20140527|Success||Automated|DSPRN1234567
*2*|AAA|1234567894561237|STOP|20140527|Success||Automated|DPSRN1234568
*3*|2
I need to read the lines beginning with 2 so I done:
s = new Scanner(new BufferedReader(new FileReader("example.dat")));
while (s.hasNext()) {
String str1 = s.nextLine ();
if(str1.startsWith("*2*")) {
System.out.print(str1);
}
}
So this will read the whole line I'm fine with that, Now my issue is I need to extract the 2nd line beginning with numbers the 4th with numbers the 5th with success and the 7th(DPSRN).
I was thinking about using a String delimiter with | as the delimiter but I'm not sure where to go after this any help would be great.

You should use String.split("|"), it will give you an array - String[]

Try following:
String test="*2*|AAA|1234567894561236|STOP|20140527|Success||Automated|DSPRN1234567";
String tok[]=test.split("\\|");
for(String s:tok){
System.out.println(s);
}
Output :
*2*
AAA
1234567894561236
STOP
20140527
Success
Automated
DSPRN1234567
What you require will be placed at tok[2], tok[4], tok[5] and tok[8].

Just split the returned line based on your search, which would return an array of String elements where you can retrieve your elements based on their index:
s = new Scanner(new BufferedReader(new FileReader("example.dat")));
String searchLine = "";
while (s.hasNext()) {
searchLine = s.nextLine();
if(searchLine.startsWith("*2*")) {
break;
}
}
String[] strs = searchLine.split("|");
String secondArgument = strs[2];
String forthArgument = strs[4];
String fifthArgument = strs[5];
String seventhArgument = strs[7];
System.out.println(secondArgument);
System.out.println(forthArgument);
System.out.println(fifthArgument);
System.out.println(seventhArgument);

Scanning, spliting and assigning values from a text file

I'm having trouble scanning a given file for certain words and assigning them to variables, so far I've chosen to use Scanner over BufferedReader because It's more familiar. I'm given a text file and this particular part I'm trying to read the first two words of each line (potentially unlimited lines) and maybe add them to an array of sorts. This is what I have:
File file = new File("example.txt");
Scanner sc = new Scanner(file);
while (sc.hasNextLine()) {
String line = sc.nextLine();
String[] ary = line.split(",");
I know It' a fair distance off, however I'm new to coding and cannot get past this wall...
An example input would be...
ExampleA ExampleAA, <other items seperated by ",">
ExampleB ExampleBB, <other items spereated by ",">
...
and the proposed output
VariableA = ExampleA ExampleAA
VariableB = ExampleB ExampleBB
...

You can try something like this
File file = new File("D:\\test.txt");
Scanner sc = new Scanner(file);
List<String> list =new ArrayList<>();
int i=0;
while (sc.hasNextLine()) {
list.add(sc.nextLine().split(",",2)[0]);
i++;
}
char point='A';
for(String str:list){
System.out.println("Variable"+point+" = "+str);
point++;
}
My input:
ExampleA ExampleAA, <other items seperated by ",">
ExampleB ExampleBB, <other items spereated by ",">
Out put:
VariableA = ExampleA ExampleAA
VariableB = ExampleB ExampleBB

To rephrase, you are looking to read the first 2 words of a line (everything before the first comma) and store it in a variable to process further.
To do so, your current code looks fine, however, when you grab the line's data, use the substring function in conjunction with indexOf to just get the first part of the String before the comma. After that, you can do whatever processing you want to do with it.
In your current code, ary[0] should give you the first 2 words.

public static void main(String[] args)
{
File file = new File("example.txt");
FileReader fr = new FileReader(file);
BufferedReader br = new BufferedReader(fr);
String line = "";
List l = new ArrayList();
while ((line = br.readLine()) != null) {
System.out.println(line);
line = line.trim(); // remove unwanted characters at the end of line
String[] arr = line.split(",");
String[] ary = arr[0].split(" ");
String firstTwoWords[] = new String[2];
firstTwoWords[0] = ary[0];
firstTwoWords[1] = ary[1];
l.add(firstTwoWords);
}
Iterator it = l.iterator();
while (it.hasNext()) {
String firstTwoWords[] = (String[]) it.next();
System.out.println(firstTwoWords[0] + " " + firstTwoWords[1]);
}
}

How to read data from a text file into arrays in Java

I am having trouble with a programming assignment. I need to read data from a txt file and store it in parallel arrays. The txt file contents are formatted like this:
Line1: Stringwith466numbers
Line2: String with a few words
Line3(int): 4
Line4: Stringwith4643numbers
Line5: String with another few words
Line6(int): 9
Note: The "Line1: ", "Line2: ", etc is just for display purposes and isn't actually in the txt file.
As you can see it goes in a pattern of threes. Each entry to the txt file is three lines, two strings and one int.
I would like to read the first line into an array, the second into another, and the third into an int array. Then the fourth line would be added to the first array, the 5th line to the second array and the 6th line into the third array.
I have tried to write the code for this but can't get it working:
//Create Parallel Arrays
String[] moduleCodes = new String[3];
String[] moduleNames = new String[3];
int[] numberOfStudents = new int[3];
String fileName = "myfile.txt";
readFileContent(fileName, moduleCodes, moduleNames, numberOfStudents);
private static void readFileContent(String fileName, String[] moduleCodes, String[] moduleNames, int[] numberOfStudents) throws FileNotFoundException {
// Create File Object
File file = new File(fileName);
if (file.exists())
{
Scanner scan = new Scanner(file);
int counter = 0;
while(scan.hasNext())
{
String code = scan.next();
String moduleName = scan.next();
int totalPurchase = scan.nextInt();
moduleCodes[counter] = code;
moduleNames[counter] = moduleName;
numberOfStudents[counter] = totalPurchase;
counter++;
}
}
}
The above code doesn't work properly. When I try to print out an element of the array. it returns null for the string arrays and 0 for the int arrays suggesting that the code to read the data in isn't working.
Any suggestions or guidance much appreciated as it's getting frustrating at this point.

The fact that only null's get printed suggests that the file doesn't exist or is empty (if you print it correctly).
It's a good idea to put in some checking to make sure everything is fine:
if (!file.exists())
System.out.println("The file " + fileName + " doesn't exist!");
Or you can actually just skip the above and also take out the if (file.exists()) line in your code and let the FileNotFoundException get thrown.
Another problem is that next splits things by white-space (by default), the problem is that there is white-space on that second line.
nextLine should work:
String code = scan.nextLine();
String moduleName = scan.nextLine();
int totalPurchase = Integer.parseInt(scan.nextLine());
Or, changing the delimiter should also work: (with your code as is)
scan.useDelimiter("\\r?\\n");

You are reading line so try this:
while(scan.hasNextLine()){
String code = scan.nextLine();
String moduleName = scan.nextLine();
int totalPurchase = Integer.pasreInt(scan.nextLine().trim());
moduleCodes[counter] = code;
moduleNames[counter] = moduleName;
numberOfStudents[counter] = totalPurchase;
counter++;
}

String code = scan.nextLine();
String moduleName = scan.nextLine();
int totalPurchase = scan.nextInt();
scan.nextLine()
This will move scanner to proper position after reading int.