Connect some in Java Txt file [closed]

I have some Txt file I want to connect them and generate a text file How will I execute in Java?

file1.txt file2.txt

Connection results

file3.txt

So file1 Txt followed by File2 txt

Solution

Read and write the target file one by one As follows:

OutputStream out = new FileOutputStream(outFile);
    byte[] buf = new byte[n];
    for (String file : files) {
        InputStream in = new FileInputStream(file);
        int b = 0;
        while ( (b = in.read(buf)) >= 0) {
            out.write(buf,b);
            out.flush();
        }
    }
    out.close();