How to best format input read from a file to a string

Question

I am trying to set up a class to convert input read from an xml-file to a java-string, which I can pass on to a web service.
My attempt is probably not the smartest, but what I did was to set up a for-loop, which iterates through each line in the xml, appending "\n" to the end of each line, before storing them in a variable, which is loaded into an arraylist. When there are no more lines to read in the xml-file, the for-loop should terminate and the contents of the ArrayList should be written to a string, which is then returned.
Below is my attempt to implement this - thanks in advance!
import java.io.*;
import java.util.*;
public class RequestBuilder {
     private String _filename, output;
     //Constructor method
     RequestBuilder(String filename){
          String line;
          _filename = filename;
          //Sets up a array to store each line of XML read from a file
          ArrayList<String> lineList;
     lineList = new ArrayList<String>();
          try {
               //Sets up a filereader and a buffer
               FileReader fr = new FileReader(_filename);
               BufferedReader br = new BufferedReader(fr);
               //Iterates through each element of the arraylist until empty
               for (String o : lineList){
               //Stores a single linein a variable and appends a line-break
               line = br.readLine() + "\n";
               //Addseach line to the arraylist
               lineList.add(line);
               //Closes the filereader
               fr.close();
               //Writes the arraylist to a string
               output = lineList.toString();
          } catch (FileNotFoundException e) {
               e.printStackTrace();
          } catch (IOException e) {
               e.printStackTrace();
     public String getRequest(){
          return output;
}

Answer 1

799992 wrote:
Well, the reason for doing an ArrayList was that I had to process each line with line breaks and escape characters, but I know realize that I can do the same thing by summing the lines for each iteration directly intro a string like below - it works :-)
Apparently the filereader takes care of double-quotes as I don't see any difference in the output when I disable the logic I made, which substitutes " with \", can anyone confirm this?
The code I ended up using:
     //Sets up a filereader and a buffer
               FileReader fr = new FileReader(_filename);
               BufferedReader br = new BufferedReader(fr); 
               //initializes the output variable with the first line from the file
               output = br.readLine() + "\n";
               while (br.ready() == true) {
                    //reads each line, saves it in a variable and appends line breaks
                    line = br.readLine() + "\n";
                    //Replaces adds escape character to any double-quotes (apparently not neccessary?)
                    tmpLine = line.replaceAll("\"", "\\\"");
                    line = tmpLine;
                    //sums each line in the current string
                    output = output + line;
As EJP said you can directly write to the webservice. If you want to check for yourself what the result looks like just read the file without adding anything.
public String readFile(){
     String xmlString = "";
          try{
               String line = null;
               xmlFile = new File(//file);
               reader = new BufferedReader(new FileReader(xmlFile));
                    while((line = reader.readLine()) != null){
                         xmlString += line;
          catch(FileNotFoundException e){
                    e.printStackTrace();
          catch(IOException e){
                    e.printStackTrace();
     return xmlString.replaceAll("\\s+"," ").trim();//remove spaces
}