UnicodeBOMInputStreamUsage.java

// (‑●‑●)> released under the WTFPL v2 license, by Gregory Pakosz (@gpakosz)

package net.pempek.unicode;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.io.PrintStream;

public final class UnicodeBOMInputStreamUsage
{
  public static void main(final String[] args) throws Exception
  {
    // here we're setting the output encoding to US-ASCII on purpose
    // would you choose UTF-8, Java would read it with U+FEFF, see
    // http://www.fileformat.info/info/unicode/char/feff/
    //
    // with US-ASCII, the BOM is replaced by ?
    PrintStream out = new PrintStream(System.out, true, "US-ASCII");

    FileInputStream fis = new FileInputStream("offending_bom.txt");
    UnicodeBOMInputStream ubis = new UnicodeBOMInputStream(fis);

    out.println("Detected BOM: " + ubis.getBOM());

    out.print("Reading the content of the file without skipping the BOM: ");
    InputStreamReader isr = new InputStreamReader(ubis);
    BufferedReader br = new BufferedReader(isr);

    out.println(br.readLine());

    br.close();
    isr.close();
    ubis.close();
    fis.close();

    fis = new FileInputStream("offending_bom.txt");
    ubis = new UnicodeBOMInputStream(fis);
    ubis.skipBOM();

    out.print("Reading the content of the file after skipping the BOM: ");
    isr = new InputStreamReader(ubis);
    br = new BufferedReader(isr);

    out.println(br.readLine());

    br.close();
    isr.close();
    ubis.close();
    fis.close();
  }

} // UnicodeBOMInputStreamUsage