Simplest way to concatenate multi lines of text in java through File Handling

I tried concatenating 2 lines of text in a given text file and printing the output to the console. My code is very complicated, is there a simpler method to achieve this by using FileHandling basic concepts ?

import java.io.*;


public class ConcatText{

    public static void main(String[] args){
    
        BufferedReader br = null;
        try{
            String currentLine;
            br = new BufferedReader(new FileReader("C:\\Users\\123\\Documents\\CS105\\FileHandling\\concat.file.text"));
            
            StringBuffer text1 = new StringBuffer (br.readLine());
            StringBuffer text2 = new StringBuffer(br.readLine()); 
            text1.append(text2);
            String str = text1.toString();
            str = str.trim();
            String array[] = str.split(" ");
            StringBuffer result = new StringBuffer();
            for(int i=0; i<array.length; i++) {
               result.append(array[i]);
              }
              System.out.println(result);
            }
        catch(IOException e){
            e.printStackTrace();
        }finally{
            try{
                if(br != null){
                    br.close();
                }
                }catch(IOException e){
                    e.printStackTrace();
                    
                }
            }   
                
        }
        
    
    
    }

The text file is as follows :
GTAGCTAGCTAGC
AGCCACGTA

the output should be as follows (concatenation of the text file Strings) :
GTAGCTAGCTAGCAGCCACGTA

If you are using java 8 or newer, the simplest way would be:

List<String> lines = Files.readAllLines(Paths.get(filePath));
String result = String.join("", lines);

If you are using java 7, at least you can use try with resources to reduce the clutter in the code, like this:

try (BufferedReader br = new BufferedReader(new FileReader(filePath))) {
   StringBuffer text1 = new StringBuffer (br.readLine());
   StringBuffer text2 = new StringBuffer(br.readLine()); 
   // ...
}catch(IOException e){
   e.printStackTrace();
}

This way, resources will be autoclosed and you don't need to call br.close().