binaryfile.java

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        return inputReader.skipBytes(n);
    }

    /**
     * Get the index of the next character to be read
     * 
     * @return the index
     * @exception IOException Any IO errors that occur in accessing the
     *            underlying file
     */
    public long getFilePointer() throws IOException {
        return inputReader.getFilePointer();
    }

    /**
     * Set the index of the next character to be read.
     * 
     * @param pos the position to seek to.
     * @exception IOException Any IO Errors that occur in seeking the underlying
     *            file.
     */
    public void seek(long pos) throws IOException {
        inputReader.seek(pos);
    }

    /**
     * The length of the InputReader source.
     */
    public long length() throws IOException {
        return inputReader.length();
    }

    /**
     * Return how many bytes left to be read in the file.
     * 
     * @return the number of bytes remaining to be read (counted in bytes)
     * @exception IOException Any IO errors encountered in accessing the file
     */
    public long available() throws IOException {
        return inputReader.available();
    }

    /**
     * Closes the underlying file, but with a chance for re-opening if accessed
     * again.
     * 
     * @exception IOException Any IO errors encountered in accessing the file
     */
    public void close() throws IOException {
        if (inputReader != null) {
            inputReader.close();
            openCount--;
        }
    }

    /**
     * Closes underlying file, get rid of resources and knowledge of file. To be
     * called when you don't need the file any more.
     * 
     * @throws IOException
     */
    public void dispose() throws IOException {
        close();
        inputReader = null;
    }

    /**
     * Read from the file.
     * 
     * @return one byte from the file. -1 for EOF
     * @exception IOException Any IO errors encountered in reading from the file
     */
    public int read() throws IOException {
        return inputReader.read();
    }

    /**
     * Read from the file
     * 
     * @param b The byte array to read into
     * @param off the first array position to read into
     * @param len the number of bytes to read
     * @return the number of bytes read
     * @exception IOException Any IO errors encountered in reading from the file
     */
    public int read(byte b[], int off, int len) throws IOException {
        return inputReader.read(b, off, len);
    }

    /**
     * Read from the file.
     * 
     * @param b the byte array to read into. Equivelent to
     *        <code>read(b, 0, b.length)</code>
     * @return the number of bytes read
     * @exception IOException Any IO errors encountered in reading from the file
     * @see java.io.RandomAccessFile#read(byte[])
     */
    public int read(byte b[]) throws IOException {
        return inputReader.read(b);
    }

    /**
     * Read from the file.
     * 
     * @param howmany the number of bytes to read
     * @param allowless if we can return fewer bytes than requested
     * @return the array of bytes read.
     * @exception FormatException Any IO Exceptions, plus an end-of-file
     *            encountered after reading some, but now enough, bytes when
     *            allowless was <code>false</code>
     * @exception EOFException Encountered an end-of-file while allowless was
     *            <code>false</code>, but NO bytes had been read.
     */
    public byte[] readBytes(int howmany, boolean allowless)
            throws EOFException, FormatException {

        return inputReader.readBytes(howmany, allowless);
    }

    /**
     * Reads and returns a single byte, cast to a char
     * 
     * @return the byte read from the file, cast to a char
     * @exception EOFException the end-of-file has been reached, so no chars
     *            where available
     * @exception FormatException a rethrown IOException
     */
    public char readChar() throws EOFException, FormatException {
        try {
            int retv = inputReader.read();

            if (retv == -1) {
                throw new EOFException("Error in ReadChar, EOF reached");
            }
            return (char) retv;
        } catch (IOException i) {
            throw new FormatException("readChar IOException: " + i.getMessage());
        }
    }

    /**
     * Read a byte from the file, return an unsigned integer.
     * 
     * @return one byte from the file. -1 for EOF causes EOFException
     * @exception IOException Any IO errors encountered in reading from the file
     */
    public int readUnsigned() throws IOException, EOFException {
        byte b = (byte) read();
        if (b == -1) {
            throw new EOFException();
        }
        return MoreMath.signedToInt(b);
    }

    /**
     * Reads and returns a short.
     * 
     * @return the 2 bytes merged into a short, according to the current byte
     *         ordering
     * @exception EOFException there were less than 2 bytes left in the file
     * @exception FormatException rethrow of IOExceptions encountered while
     *            reading the bytes for the short
     * @see #read(byte[])
     */
    public short readShort() throws EOFException, FormatException {
        // MSBFirst must be set when we are called
        return MoreMath.BuildShort(readBytes(2, false), MSBFirst);
    }

    /**
     * Code for reading shorts that are two-byte integers, high order first, and
     * negatives are signed magnitude. Users may have to switch the bytes and
     * convert negatives to the complement they use. This can be done by putting
     * the low order byte first, then turning off bit 15 (the high order bit),
     * and then multiplying by -1." Basically they are encoded as positive
     * numbers, but bit 15 is set to 1.
     * 
     * @return
     * @throws EOFException
     * @throws FormatException
     */
    public short readShortData() throws EOFException, FormatException {
        // read in the two bytes
        byte[] bytevec = readBytes(2, false);

        // check for negative values - bit 7 of byte 0
        if (bytevec[0] < 0) {
            // mask bit 7
            bytevec[0] &= 0x7f;
            // create the short and multiply the result by -1
            return ((short) (MoreMath.BuildShort(bytevec, true) * -1));
        }
        return MoreMath.BuildShort(bytevec, true);
    }

    /**
     * Reads and returns a integer from 2 bytes.
     * 
     * @return the 2 bytes merged into a short, according to the current byte
     *         ordering, and then unsigned to int.
     * @exception EOFException there were less than 2 bytes left in the file
     * @exception FormatException rethrow of IOExceptions encountered while
     *            reading the bytes for the short
     * @see #read(byte[])
     */
    public int readUnsignedShort() throws EOFException, FormatException {
        // MSBFirst must be set when we are called
        return MoreMath.signedToInt(readShort());
    }

    /**
     * Reads and returns a long
     * 
     * @return the 4 bytes merged into a long, according to the current byte
     *         ordering
     * @exception EOFException there were less than 4 bytes left in the file
     * @exception FormatException rethrow of IOExceptions encountered while
     *            reading the bytes for the integer
     * @see #read(byte[])
     */
    public int readInteger() throws EOFException, FormatException {
        // MSBFirst must be set when we are called
        return MoreMath.BuildInteger(readBytes(4, false), MSBFirst);
    }

    public void readIntegerArray(int vec[], int offset, int len)
            throws EOFException, FormatException {
        for (int i = 0; i < len; i++) {
            vec[offset++] = readInteger();
        }
    }

    /**
     * Reads and returns a long
     * 
     * @return the 8 bytes merged into a long, according to the current byte
     *         ordering
     * @exception EOFException there were less than 8 bytes left in the file
     * @exception FormatException rethrow of IOExceptions encountered while
     *            reading the bytes for the long
     * @see #read(byte[])
     */
    public long readLong() throws EOFException, FormatException {
        return MoreMath.BuildLong(readBytes(8, false), MSBFirst);
    }

    /**
     * Reads and returns a float
     * 
     * @return the 4 bytes merged into a float, according to the current byte
     *         ordering
     * @exception EOFException there were less than 4 bytes left in the file
     * @exception FormatException rethrow of IOExceptions encountered while
     *            reading the bytes for the float
     * @see #read(byte[])
     */
    public float readFloat() throws EOFException, FormatException {
        return Float.intBitsToFloat(readInteger());
    }

    public void readFloatArray(float vec[], int offset, int len)
            throws EOFException, FormatException {
        for (int i = 0; i < len; i++) {
            vec[offset++] = readFloat();
        }
    }

    /**
     * Reads and returns a double
     * 
     * @return the 8 bytes merged into a double, according to the current byte
     *         ordering
     * @exception EOFException there were less than 8 bytes left in the file
     * @exception FormatException rethrow of IOExceptions encountered while
     *            reading the bytes for the short
     * @see #read(byte[])
     */
    public double readDouble() throws EOFException, FormatException {
        return Double.longBitsToDouble(readLong());
    }

    /**
     * Reads <code>length</code> bytes and returns a string composed of the
     * bytes cast to chars
     * 
     * @param length the number of bytes to read into the string
     * @return the composed string
     * @exception EOFException there were less than <code>length</code> bytes
     *            left in the file
     * @exception FormatException rethrow of IOExceptions encountered while
     *            reading the bytes for the short
     */
    public String readFixedLengthString(int length) throws EOFException,
            FormatException {

        byte foo[] = readBytes(length, false);
        return new String(foo, 0, length);
    }

    /**
     * Read a bytes and throw an InvalidCharException if it doesn't match
     * <code>expected</code>
     * 
     * @param expected what the next char is claimed to be
     * @exception EOFException there wasn't a byte, so we can't check for a
     *            match
     * @exception InvalidCharException throws when the character read doesn't
     *            match <code>expected</code> The .c member of the thrown
     *            exception is the actual char read
     * @exception FormatException some other error from reading the file
     */
    public void assertChar(char expected) throws EOFException, FormatException {
        char c = readChar();
        if (c != expected) {
            throw new InvalidCharException("AssertChar: expected " + expected
                    + " got " + c, c);
        }
    }

    /**
     * Reads a string until the specified delimiter or EOF is encountered
     * 
     * @param delim the end-of-string delimiter
     * @return the string that was read
     * @exception FormatException rethrow of IOExceptions from the read methods
     */
    public String readToDelimiter(char delim) throws FormatException {
        StringBuffer buildretval = new StringBuffer();
        char tmp;
        try {
            while ((tmp = readChar()) != delim)
                buildretval.append(tmp);
        } catch (EOFException e) {
            // allowable
        } catch (FormatException fe) {
            if (buildretval.length() == 0) {
                throw fe;
            }
        }
        return buildretval.toString();
    }

    /**
     * Makes sure that the file has been closed.
     * 
     * @exception Throwable what it throws.
     */
    public void finalize() throws Throwable {
        close();
        classCount--;
    }

    /**
     * Maintains a list of objects that can be closed so that other files can be
     * opened.
     */
    private static Vector closableList = new Vector();

    /**
     * Add an object that can be closed if needed. Duplicates are allowed. Only
     * holds a WeakReference, so that the object can still be garbage-collected.
     * 
     * @param it the object that can be closed
     */
    public static synchronized void addClosable(Closable it) {
        closableList.addElement(new WeakReference(it));
    }

    /**
     * Remove an object from the closable list.
     * 
     * @param it the object to remove
     */
    public static synchronized void removeClosable(Closable it) {
        for (int i = 0; i < closableList.size(); i++) {
            Object o = ((WeakReference) closableList.elementAt(i)).get();
            if ((o == it) || (o == null)) {
                closableList.removeElementAt(i);
                i--; // in case its in the list more than once
            }
        }
    }

    public static synchronized void closeClosable() {
        System.out.println("closeClosable " + closableList.size());
        for (int i = 0; i < closableList.size(); i++) {
            Closable c = (Closable) ((WeakReference) closableList.elementAt(i)).get();
            if ((c == null) || !c.close(false)) {
                closableList.removeElementAt(i);
                i--;
            }
        }
    }
}