File Android

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
class Main {
  public static String inputStream2String(InputStream inputStream) throws IOException{
    byte[] buffer = new byte[8192];
    int bytesRead;
    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    
    while((bytesRead = inputStream.read(buffer)) != -1){
      outputStream.write(buffer, 0, bytesRead);
    }
    return outputStream.toString("US-ASCII");
  }
}