Package blbutil

Class FileUtil

java.lang.Object
blbutil.FileUtil
public class FileUtil extends Object
Class FileUtil contains static methods for working with files.

  • Method Details

    • randomAccessFile

      public static RandomAccessFile randomAccessFile(File file, String mode)
      Returns a java.io.RandomAccessFile to read from or optionally to write to the specified file. If the input stream cannot be opened, an error message will be printed and the java interpreter will exit.
      Parameters:
      file - a file
      mode - the access mode as described in the documentation for the java.io.RandomAccessFile constructors
      Returns:
      a java.io.RandomAccessFile
      Throws:
      NullPointerException - if file == null || mode == null

    • bufferedInputStream

      public static InputStream bufferedInputStream(File file)
      Returns an buffered java.io.InputStream with default buffer size reading from the specified file. If the input stream cannot be opened, an error message will be printed and the java interpreter will exit.
      Parameters:
      file - a file
      Returns:
      an buffered java.io.InputStream
      Throws:
      NullPointerException - if file == null

    • bufferedOutputStream

      public static OutputStream bufferedOutputStream(File file)
      Returns an buffered java.io.OutputStream with default buffer size writing to the specified file. If the file cannot be opened for writing, an error message will be printed and the Java Virtual Machine will exit.
      Parameters:
      file - a file
      Returns:
      a buffered java.io.OutputStream
      Throws:
      NullPointerException - if file == null

    • bufferedOutputStream

      public static OutputStream bufferedOutputStream(File file, boolean append)
      Returns an buffered java.io.OutputStream with default buffer size writing to the specified file. If the file cannot be opened for writing, an error message will be printed and the Java Virtual Machine will exit. If the specified file exists and append is false, bytes written by the returned java.io.OutputStream will overwrite the previously existing file.
      Parameters:
      file - a file
      append - true if bytes will be appended to the end of the file
      Returns:
      an buffered java.io.OutputStream
      Throws:
      NullPointerException - if file == null

    • stdOutPrintWriter

      public static PrintWriter stdOutPrintWriter()
      Returns a java.io.PrintWriter that writes to standard out.
      Returns:
      a java.io.PrintWriter that writes to standard out

    • gzipPrintWriter

      public static PrintWriter gzipPrintWriter(File file)
      Returns a buffered java.io.PrintWriter writing to the specified file. The resulting file will be compressed using the GZIP compression algorithm. If the file cannot be opened, an error message will be printed and the java interpreter will exit. If the specified file exists, bytes written by the returned PrintWriter will overwrite the previously existing file.
      Parameters:
      file - a file
      Returns:
      a java.io.PrintWriter writing to the specified file
      Throws:
      NullPointerException - if file == null

    • gzipPrintWriter

      public static PrintWriter gzipPrintWriter(File file, boolean append)
      Returns a buffered java.io.PrintWriter writing to the specified file. The resulting file will be compressed using the GZIP compression algorithm. If the file cannot be opened, an error message will be printed and the java interpreter will exit. If the specified file exists and append is false, bytes written by the returned PrintWriter will overwrite the previously existing file.
      Parameters:
      file - a file
      append - true if bytes will be appended to the end of the file
      Returns:
      a java.io.PrintWriter writing to the specified file
      Throws:
      NullPointerException - if file == null

    • bgzipPrintWriter

      public static PrintWriter bgzipPrintWriter(File file)
      Returns a buffered java.io.PrintWriter that compresses data using the BGZIP algorithm and writes the compressed data to the specified file. The close() method of the returned PrintWriter will write an empty BGZIP block to the end of the output stream. If the file cannot be opened for writing, an error message will be printed and the Java Virtual Machine will exit. If the specified file exists, bytes written by the returned PrintWriter will overwrite the previously existing file.
      Parameters:
      file - a file
      Returns:
      a buffered java.io.PrintWriter
      Throws:
      NullPointerException - if file == null

    • bgzipPrintWriter

      public static PrintWriter bgzipPrintWriter(File file, boolean append)
      Returns a buffered java.io.PrintWriter that compresses data using the BGZIP algorithm and writes the compressed data to the specified file. The close() method of the returned PrintWriter will write an empty BGZIP block to the end of the output stream. If the file cannot be opened for writing, an error message will be printed and the Java Virtual Machine will exit. If the specified file exists and append is false, bytes written by the returned PrintWriter will overwrite the previously existing file.
      Parameters:
      file - a file
      append - true if bytes will be appended to the end of the file
      Returns:
      a buffered java.io.PrintWriter
      Throws:
      NullPointerException - if file == null

    • printWriter

      public static PrintWriter printWriter(File file)
      Returns a buffered java.io.PrintWriter writing to the specified file. If the file cannot be opened, an error message will be printed and the Java Virtual Machine will exit. If the specified file exists, bytes written by the returned PrintWriter will overwrite the previously existing file.
      Parameters:
      file - a file
      Returns:
      a buffered java.io.PrintWriter writing to the specified file
      Throws:
      NullPointerException - if file == null

    • printWriter

      public static PrintWriter printWriter(File file, boolean append)
      Returns a buffered java.io.PrintWriter writing to the specified file. If the file cannot be opened, an error message will be printed and the Java Virtual Machine will exit. If the specified file exists and append is false, bytes written by the returned PrintWriter will overwrite the previously existing file.
      Parameters:
      file - a file
      append - true if the data will be appended to the end of any existing file
      Returns:
      a buffered java.io.PrintWriter writing to the specified file
      Throws:
      NullPointerException - if file == null

    • nonBufferedPrintWriter

      public static PrintWriter nonBufferedPrintWriter(File file, boolean append)
      Returns an unbuffered java.io.PrintWriter writing to the specified file. If the file cannot be opened, an error message will be printed and the Java Virtual Machine will exit. If the specified file exists and append is false, bytes written by the returned PrintWriter will overwrite the previously existing file.
      Parameters:
      file - a file
      append - true if the data will be appended to the end of any existing file
      Returns:
      a non-buffered java.io.PrintWriter writing to the specified file
      Throws:
      NullPointerException - if file == null

    • skipNBytes

      public static void skipNBytes(InputStream is, long nBytes, String source)
      Skips and discards the specified number of bytes of data from the specified input stream. No bytes are skipped if the specified number of bytes is negative or 0. The method blocks until the specified number of bytes have been skipped or an IOException exception is thrown. The Java Virtual Machine will exit with an error message if the end of file is reached before the specified number of bytes are skipped or if an IOException is thrown.
      Parameters:
      is - an input stream
      nBytes - the number of bytes to skip
      source - a string description of the input stream source

    • tempFile

      public static File tempFile(String prefix)
      Returns a temporary File that will be deleted when the Java virtual machine exits.
      Parameters:
      prefix - the filename prefix.
      Returns:
      a File a new empty file.
      Throws:
      IllegalArgumentException - if prefix contains fewer than three characters

    • tempFile

      public static File tempFile(String prefix, File directory)
      Creates and returns a new empty temporary file in the specified directory. The temporary file will be deleted when the JVM terminates if the JVM terminates normally.
      Parameters:
      prefix - a prefix of at least 3 characters for the temporary filename
      directory - the directory in which the temporary file is to be created.
      Returns:
      a new empty temporary file in the specified directory.
      Throws:
      NullPointerException - if prefix == null || directory == null