* A Java formatter for printf-style format strings,
* as seen in the C programming language. This differs from the
* C interpretation of such strings by performing much stricter
* checking of format specifications and their corresponding
* arguments. While unknown conversions will be ignored in C,
* and invalid conversions will only produce compiler warnings,
* the Java version utilises a full range of run-time exceptions to
* handle these cases. The Java version is also more customisable
* by virtue of the provision of the {@link Formattable} interface,
* which allows an arbitrary class to be formatted by the formatter.
*
* The formatter is accessible by more convienient static methods.
* For example, streams now have appropriate format methods
* (the equivalent of fprintf) as do String
* objects (the equivalent of sprintf).
*
* Note: the formatter is not thread-safe. For * multi-threaded access, external synchronization should be provided. *
* * @author Tom Tromey (tromey@redhat.com) * @author Andrew John Hughes (gnu_andrew@member.fsf.org) * @since 1.5 */ public final class Formatter implements Closeable, Flushable { /** * The output of the formatter. */ private Appendable out; /** * The locale used by the formatter. */ private Locale locale; /** * Whether or not the formatter is closed. */ private boolean closed; /** * The last I/O exception thrown by the output stream. */ private IOException ioException; // Some state used when actually formatting. /** * The format string. */ private String format; /** * The current index into the string. */ private int index; /** * The length of the format string. */ private int length; /** * The formatting locale. */ private Locale fmtLocale; // Note that we include '-' twice. The flags are ordered to // correspond to the values in FormattableFlags, and there is no // flag (in the sense of this field used when parsing) for // UPPERCASE; the second '-' serves as a placeholder. /** * A string used to index into the formattable flags. */ private static final String FLAGS = "--#+ 0,("; /** * The system line separator. */ private static final String lineSeparator = SystemProperties.getProperty("line.separator"); /** * The type of numeric output format for a {@link BigDecimal}. */ public enum BigDecimalLayoutForm { DECIMAL_FLOAT, SCIENTIFIC } /** * Constructs a newFormatter using the default
* locale and a {@link StringBuilder} as the output stream.
*/
public Formatter()
{
this(null, Locale.getDefault());
}
/**
* Constructs a new Formatter using the specified
* locale and a {@link StringBuilder} as the output stream.
* If the locale is null, then no localization
* is applied.
*
* @param loc the locale to use.
*/
public Formatter(Locale loc)
{
this(null, loc);
}
/**
* Constructs a new Formatter using the default
* locale and the specified output stream.
*
* @param app the output stream to use.
*/
public Formatter(Appendable app)
{
this(app, Locale.getDefault());
}
/**
* Constructs a new Formatter using the specified
* locale and the specified output stream. If the locale is
* null, then no localization is applied.
*
* @param app the output stream to use.
* @param loc the locale to use.
*/
public Formatter(Appendable app, Locale loc)
{
this.out = app == null ? new StringBuilder() : app;
this.locale = loc;
}
/**
* Constructs a new Formatter using the default
* locale and character set, with the specified file as the
* output stream.
*
* @param file the file to use for output.
* @throws FileNotFoundException if the file does not exist
* and can not be created.
* @throws SecurityException if a security manager is present
* and doesn't allow writing to the file.
*/
public Formatter(File file)
throws FileNotFoundException
{
this(new OutputStreamWriter(new FileOutputStream(file)));
}
/**
* Constructs a new Formatter using the default
* locale, with the specified file as the output stream
* and the supplied character set.
*
* @param file the file to use for output.
* @param charset the character set to use for output.
* @throws FileNotFoundException if the file does not exist
* and can not be created.
* @throws SecurityException if a security manager is present
* and doesn't allow writing to the file.
* @throws UnsupportedEncodingException if the supplied character
* set is not supported.
*/
public Formatter(File file, String charset)
throws FileNotFoundException, UnsupportedEncodingException
{
this(file, charset, Locale.getDefault());
}
/**
* Constructs a new Formatter using the specified
* file as the output stream with the supplied character set
* and locale. If the locale is null, then no
* localization is applied.
*
* @param file the file to use for output.
* @param charset the character set to use for output.
* @param loc the locale to use.
* @throws FileNotFoundException if the file does not exist
* and can not be created.
* @throws SecurityException if a security manager is present
* and doesn't allow writing to the file.
* @throws UnsupportedEncodingException if the supplied character
* set is not supported.
*/
public Formatter(File file, String charset, Locale loc)
throws FileNotFoundException, UnsupportedEncodingException
{
this(new OutputStreamWriter(new FileOutputStream(file), charset),
loc);
}
/**
* Constructs a new Formatter using the default
* locale and character set, with the specified output stream.
*
* @param out the output stream to use.
*/
public Formatter(OutputStream out)
{
this(new OutputStreamWriter(out));
}
/**
* Constructs a new Formatter using the default
* locale, with the specified file output stream and the
* supplied character set.
*
* @param out the output stream.
* @param charset the character set to use for output.
* @throws UnsupportedEncodingException if the supplied character
* set is not supported.
*/
public Formatter(OutputStream out, String charset)
throws UnsupportedEncodingException
{
this(out, charset, Locale.getDefault());
}
/**
* Constructs a new Formatter using the specified
* output stream with the supplied character set and locale.
* If the locale is null, then no localization is
* applied.
*
* @param out the output stream.
* @param charset the character set to use for output.
* @param loc the locale to use.
* @throws UnsupportedEncodingException if the supplied character
* set is not supported.
*/
public Formatter(OutputStream out, String charset, Locale loc)
throws UnsupportedEncodingException
{
this(new OutputStreamWriter(out, charset), loc);
}
/**
* Constructs a new Formatter using the default
* locale with the specified output stream. The character
* set used is that of the output stream.
*
* @param out the output stream to use.
*/
public Formatter(PrintStream out)
{
this((Appendable) out);
}
/**
* Constructs a new Formatter using the default
* locale and character set, with the specified file as the
* output stream.
*
* @param file the file to use for output.
* @throws FileNotFoundException if the file does not exist
* and can not be created.
* @throws SecurityException if a security manager is present
* and doesn't allow writing to the file.
*/
public Formatter(String file) throws FileNotFoundException
{
this(new OutputStreamWriter(new FileOutputStream(file)));
}
/**
* Constructs a new Formatter using the default
* locale, with the specified file as the output stream
* and the supplied character set.
*
* @param file the file to use for output.
* @param charset the character set to use for output.
* @throws FileNotFoundException if the file does not exist
* and can not be created.
* @throws SecurityException if a security manager is present
* and doesn't allow writing to the file.
* @throws UnsupportedEncodingException if the supplied character
* set is not supported.
*/
public Formatter(String file, String charset)
throws FileNotFoundException, UnsupportedEncodingException
{
this(file, charset, Locale.getDefault());
}
/**
* Constructs a new Formatter using the specified
* file as the output stream with the supplied character set
* and locale. If the locale is null, then no
* localization is applied.
*
* @param file the file to use for output.
* @param charset the character set to use for output.
* @param loc the locale to use.
* @throws FileNotFoundException if the file does not exist
* and can not be created.
* @throws SecurityException if a security manager is present
* and doesn't allow writing to the file.
* @throws UnsupportedEncodingException if the supplied character
* set is not supported.
*/
public Formatter(String file, String charset, Locale loc)
throws FileNotFoundException, UnsupportedEncodingException
{
this(new OutputStreamWriter(new FileOutputStream(file), charset),
loc);
}
/**
* Closes the formatter, so as to release used resources.
* If the underlying output stream supports the {@link Closeable}
* interface, then this is also closed. Attempts to use
* a formatter instance, via any method other than
* {@link #ioException()}, after closure results in a
* {@link FormatterClosedException}.
*/
public void close()
{
if (closed)
return;
try
{
if (out instanceof Closeable)
((Closeable) out).close();
}
catch (IOException _)
{
// FIXME: do we ignore these or do we set ioException?
// The docs seem to indicate that we should ignore.
}
closed = true;
}
/**
* Flushes the formatter, writing any cached data to the output
* stream. If the underlying output stream supports the
* {@link Flushable} interface, it is also flushed.
*
* @throws FormatterClosedException if the formatter is closed.
*/
public void flush()
{
if (closed)
throw new FormatterClosedException();
try
{
if (out instanceof Flushable)
((Flushable) out).flush();
}
catch (IOException _)
{
// FIXME: do we ignore these or do we set ioException?
// The docs seem to indicate that we should ignore.
}
}
/**
* Return the name corresponding to a flag.
*
* @param flags the flag to return the name of.
* @return the name of the flag.
*/
private String getName(int flags)
{
// FIXME: do we want all the flags in here?
// Or should we redo how this is reported?
int bit = Integer.numberOfTrailingZeros(flags);
return FLAGS.substring(bit, bit + 1);
}
/**
* Verify the flags passed to a conversion.
*
* @param flags the flags to verify.
* @param allowed the allowed flags mask.
* @param conversion the conversion character.
*/
private void checkFlags(int flags, int allowed, char conversion)
{
flags &= ~allowed;
if (flags != 0)
throw new FormatFlagsConversionMismatchException(getName(flags),
conversion);
}
/**
* Throw an exception if a precision was specified.
*
* @param precision the precision value (-1 indicates not specified).
*/
private void noPrecision(int precision)
{
if (precision != -1)
throw new IllegalFormatPrecisionException(precision);
}
/**
* Apply the numeric localization algorithm to a StringBuilder.
*
* @param builder the builder to apply to.
* @param flags the formatting flags to use.
* @param width the width of the numeric value.
* @param isNegative true if the value is negative.
*/
private void applyLocalization(CPStringBuilder builder, int flags, int width,
boolean isNegative)
{
DecimalFormatSymbols dfsyms;
if (fmtLocale == null)
dfsyms = new DecimalFormatSymbols();
else
dfsyms = new DecimalFormatSymbols(fmtLocale);
// First replace each digit.
char zeroDigit = dfsyms.getZeroDigit();
int decimalOffset = -1;
for (int i = builder.length() - 1; i >= 0; --i)
{
char c = builder.charAt(i);
if (c >= '0' && c <= '9')
builder.setCharAt(i, (char) (c - '0' + zeroDigit));
else if (c == '.')
{
assert decimalOffset == -1;
decimalOffset = i;
}
}
// Localize the decimal separator.
if (decimalOffset != -1)
{
builder.deleteCharAt(decimalOffset);
builder.insert(decimalOffset, dfsyms.getDecimalSeparator());
}
// Insert the grouping separators.
if ((flags & FormattableFlags.COMMA) != 0)
{
char groupSeparator = dfsyms.getGroupingSeparator();
int groupSize = 3; // FIXME
int offset = (decimalOffset == -1) ? builder.length() : decimalOffset;
// We use '>' because we don't want to insert a separator
// before the first digit.
for (int i = offset - groupSize; i > 0; i -= groupSize)
builder.insert(i, groupSeparator);
}
if ((flags & FormattableFlags.ZERO) != 0)
{
// Zero fill. Note that according to the algorithm we do not
// insert grouping separators here.
for (int i = width - builder.length(); i > 0; --i)
builder.insert(0, zeroDigit);
}
if (isNegative)
{
if ((flags & FormattableFlags.PAREN) != 0)
{
builder.insert(0, '(');
builder.append(')');
}
else
builder.insert(0, '-');
}
else if ((flags & FormattableFlags.PLUS) != 0)
builder.insert(0, '+');
else if ((flags & FormattableFlags.SPACE) != 0)
builder.insert(0, ' ');
}
/**
* A helper method that handles emitting a String after applying
* precision, width, justification, and upper case flags.
*
* @param arg the string to emit.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @throws IOException if the output stream throws an I/O error.
*/
private void genericFormat(String arg, int flags, int width, int precision)
throws IOException
{
if ((flags & FormattableFlags.UPPERCASE) != 0)
{
if (fmtLocale == null)
arg = arg.toUpperCase();
else
arg = arg.toUpperCase(fmtLocale);
}
if (precision >= 0 && arg.length() > precision)
arg = arg.substring(0, precision);
boolean leftJustify = (flags & FormattableFlags.LEFT_JUSTIFY) != 0;
if (leftJustify && width == -1)
throw new MissingFormatWidthException("fixme");
if (! leftJustify && arg.length() < width)
{
for (int i = width - arg.length(); i > 0; --i)
out.append(' ');
}
out.append(arg);
if (leftJustify && arg.length() < width)
{
for (int i = width - arg.length(); i > 0; --i)
out.append(' ');
}
}
/**
* Emit a boolean.
*
* @param arg the boolean to emit.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param conversion the conversion character.
* @throws IOException if the output stream throws an I/O error.
*/
private void booleanFormat(Object arg, int flags, int width, int precision,
char conversion)
throws IOException
{
checkFlags(flags,
FormattableFlags.LEFT_JUSTIFY | FormattableFlags.UPPERCASE,
conversion);
String result;
if (arg instanceof Boolean)
result = String.valueOf((Boolean) arg);
else
result = arg == null ? "false" : "true";
genericFormat(result, flags, width, precision);
}
/**
* Emit a hash code.
*
* @param arg the hash code to emit.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param conversion the conversion character.
* @throws IOException if the output stream throws an I/O error.
*/
private void hashCodeFormat(Object arg, int flags, int width, int precision,
char conversion)
throws IOException
{
checkFlags(flags,
FormattableFlags.LEFT_JUSTIFY | FormattableFlags.UPPERCASE,
conversion);
genericFormat(arg == null ? "null" : Integer.toHexString(arg.hashCode()),
flags, width, precision);
}
/**
* Emit a String or Formattable conversion.
*
* @param arg the String or Formattable to emit.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param conversion the conversion character.
* @throws IOException if the output stream throws an I/O error.
*/
private void stringFormat(Object arg, int flags, int width, int precision,
char conversion)
throws IOException
{
if (arg instanceof Formattable)
{
checkFlags(flags,
(FormattableFlags.LEFT_JUSTIFY
| FormattableFlags.UPPERCASE
| FormattableFlags.ALTERNATE),
conversion);
Formattable fmt = (Formattable) arg;
fmt.formatTo(this, flags, width, precision);
}
else
{
checkFlags(flags,
FormattableFlags.LEFT_JUSTIFY | FormattableFlags.UPPERCASE,
conversion);
genericFormat(arg == null ? "null" : arg.toString(), flags, width,
precision);
}
}
/**
* Emit a character.
*
* @param arg the character to emit.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param conversion the conversion character.
* @throws IOException if the output stream throws an I/O error.
*/
private void characterFormat(Object arg, int flags, int width, int precision,
char conversion)
throws IOException
{
checkFlags(flags,
FormattableFlags.LEFT_JUSTIFY | FormattableFlags.UPPERCASE,
conversion);
noPrecision(precision);
int theChar;
if (arg instanceof Character)
theChar = ((Character) arg).charValue();
else if (arg instanceof Byte)
theChar = (char) (((Byte) arg).byteValue ());
else if (arg instanceof Short)
theChar = (char) (((Short) arg).shortValue ());
else if (arg instanceof Integer)
{
theChar = ((Integer) arg).intValue();
if (! Character.isValidCodePoint(theChar))
throw new IllegalFormatCodePointException(theChar);
}
else
throw new IllegalFormatConversionException(conversion, arg.getClass());
String result = new String(Character.toChars(theChar));
genericFormat(result, flags, width, precision);
}
/**
* Emit a '%'.
*
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @throws IOException if the output stream throws an I/O error.
*/
private void percentFormat(int flags, int width, int precision)
throws IOException
{
checkFlags(flags, FormattableFlags.LEFT_JUSTIFY, '%');
noPrecision(precision);
genericFormat("%", flags, width, precision);
}
/**
* Emit a newline.
*
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @throws IOException if the output stream throws an I/O error.
*/
private void newLineFormat(int flags, int width, int precision)
throws IOException
{
checkFlags(flags, 0, 'n');
noPrecision(precision);
if (width != -1)
throw new IllegalFormatWidthException(width);
genericFormat(lineSeparator, flags, width, precision);
}
/**
* Helper method to do initial formatting and checking for integral
* conversions.
*
* @param arg the formatted argument.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param radix the radix of the number.
* @param conversion the conversion character.
* @return the result.
*/
private CPStringBuilder basicIntegralConversion(Object arg, int flags,
int width, int precision,
int radix, char conversion)
{
assert radix == 8 || radix == 10 || radix == 16;
noPrecision(precision);
// Some error checking.
if ((flags & FormattableFlags.PLUS) != 0
&& (flags & FormattableFlags.SPACE) != 0)
throw new IllegalFormatFlagsException(getName(flags));
if ((flags & FormattableFlags.LEFT_JUSTIFY) != 0 && width == -1)
throw new MissingFormatWidthException("fixme");
// Do the base translation of the value to a string.
String result;
int basicFlags = (FormattableFlags.LEFT_JUSTIFY
// We already handled any possible error when
// parsing.
| FormattableFlags.UPPERCASE
| FormattableFlags.ZERO);
if (radix == 10)
basicFlags |= (FormattableFlags.PLUS
| FormattableFlags.SPACE
| FormattableFlags.COMMA
| FormattableFlags.PAREN);
else
basicFlags |= FormattableFlags.ALTERNATE;
if (arg instanceof BigInteger)
{
checkFlags(flags,
(basicFlags
| FormattableFlags.PLUS
| FormattableFlags.SPACE
| FormattableFlags.PAREN),
conversion);
BigInteger bi = (BigInteger) arg;
result = bi.toString(radix);
}
else if (arg instanceof Number
&& ! (arg instanceof Float)
&& ! (arg instanceof Double))
{
checkFlags(flags, basicFlags, conversion);
long value = ((Number) arg).longValue ();
if (radix == 8)
result = Long.toOctalString(value);
else if (radix == 16)
result = Long.toHexString(value);
else
result = Long.toString(value);
}
else
throw new IllegalFormatConversionException(conversion, arg.getClass());
return new CPStringBuilder(result);
}
/**
* Emit a hex or octal value.
*
* @param arg the hexadecimal or octal value.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param radix the radix of the number.
* @param conversion the conversion character.
* @throws IOException if the output stream throws an I/O error.
*/
private void hexOrOctalConversion(Object arg, int flags, int width,
int precision, int radix,
char conversion)
throws IOException
{
assert radix == 8 || radix == 16;
CPStringBuilder builder = basicIntegralConversion(arg, flags, width,
precision, radix,
conversion);
int insertPoint = 0;
// Insert the sign.
if (builder.charAt(0) == '-')
{
// Already inserted. Note that we don't insert a sign, since
// the only case where it is needed it BigInteger, and it has
// already been inserted by toString.
++insertPoint;
}
else if ((flags & FormattableFlags.PLUS) != 0)
{
builder.insert(insertPoint, '+');
++insertPoint;
}
else if ((flags & FormattableFlags.SPACE) != 0)
{
builder.insert(insertPoint, ' ');
++insertPoint;
}
// Insert the radix prefix.
if ((flags & FormattableFlags.ALTERNATE) != 0)
{
builder.insert(insertPoint, radix == 8 ? "0" : "0x");
insertPoint += radix == 8 ? 1 : 2;
}
// Now justify the result.
int resultWidth = builder.length();
if (resultWidth < width)
{
char fill = ((flags & FormattableFlags.ZERO) != 0) ? '0' : ' ';
if ((flags & FormattableFlags.LEFT_JUSTIFY) != 0)
{
// Left justify.
if (fill == ' ')
insertPoint = builder.length();
}
else
{
// Right justify. Insert spaces before the radix prefix
// and sign.
insertPoint = 0;
}
while (resultWidth++ < width)
builder.insert(insertPoint, fill);
}
String result = builder.toString();
if ((flags & FormattableFlags.UPPERCASE) != 0)
{
if (fmtLocale == null)
result = result.toUpperCase();
else
result = result.toUpperCase(fmtLocale);
}
out.append(result);
}
/**
* Emit a decimal value.
*
* @param arg the hexadecimal or octal value.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param conversion the conversion character.
* @throws IOException if the output stream throws an I/O error.
*/
private void decimalConversion(Object arg, int flags, int width,
int precision, char conversion)
throws IOException
{
CPStringBuilder builder = basicIntegralConversion(arg, flags, width,
precision, 10,
conversion);
boolean isNegative = false;
if (builder.charAt(0) == '-')
{
// Sign handling is done during localization.
builder.deleteCharAt(0);
isNegative = true;
}
applyLocalization(builder, flags, width, isNegative);
genericFormat(builder.toString(), flags, width, precision);
}
/**
* Emit a single date or time conversion to a StringBuilder.
*
* @param builder the builder to write to.
* @param cal the calendar to use in the conversion.
* @param conversion the formatting character to specify the type of data.
* @param syms the date formatting symbols.
*/
private void singleDateTimeConversion(CPStringBuilder builder, Calendar cal,
char conversion,
DateFormatSymbols syms)
{
int oldLen = builder.length();
int digits = -1;
switch (conversion)
{
case 'H':
builder.append(cal.get(Calendar.HOUR_OF_DAY));
digits = 2;
break;
case 'I':
builder.append(cal.get(Calendar.HOUR));
digits = 2;
break;
case 'k':
builder.append(cal.get(Calendar.HOUR_OF_DAY));
break;
case 'l':
builder.append(cal.get(Calendar.HOUR));
break;
case 'M':
builder.append(cal.get(Calendar.MINUTE));
digits = 2;
break;
case 'S':
builder.append(cal.get(Calendar.SECOND));
digits = 2;
break;
case 'N':
// FIXME: nanosecond ...
digits = 9;
break;
case 'p':
{
int ampm = cal.get(Calendar.AM_PM);
builder.append(syms.getAmPmStrings()[ampm]);
}
break;
case 'z':
{
int zone = cal.get(Calendar.ZONE_OFFSET) / (1000 * 60);
builder.append(zone);
digits = 4;
// Skip the '-' sign.
if (zone < 0)
++oldLen;
}
break;
case 'Z':
{
// FIXME: DST?
int zone = cal.get(Calendar.ZONE_OFFSET) / (1000 * 60 * 60);
String[][] zs = syms.getZoneStrings();
builder.append(zs[zone + 12][1]);
}
break;
case 's':
{
long val = cal.getTime().getTime();
builder.append(val / 1000);
}
break;
case 'Q':
{
long val = cal.getTime().getTime();
builder.append(val);
}
break;
case 'B':
{
int month = cal.get(Calendar.MONTH);
builder.append(syms.getMonths()[month]);
}
break;
case 'b':
case 'h':
{
int month = cal.get(Calendar.MONTH);
builder.append(syms.getShortMonths()[month]);
}
break;
case 'A':
{
int day = cal.get(Calendar.DAY_OF_WEEK);
builder.append(syms.getWeekdays()[day]);
}
break;
case 'a':
{
int day = cal.get(Calendar.DAY_OF_WEEK);
builder.append(syms.getShortWeekdays()[day]);
}
break;
case 'C':
builder.append(cal.get(Calendar.YEAR) / 100);
digits = 2;
break;
case 'Y':
builder.append(cal.get(Calendar.YEAR));
digits = 4;
break;
case 'y':
builder.append(cal.get(Calendar.YEAR) % 100);
digits = 2;
break;
case 'j':
builder.append(cal.get(Calendar.DAY_OF_YEAR));
digits = 3;
break;
case 'm':
builder.append(cal.get(Calendar.MONTH) + 1);
digits = 2;
break;
case 'd':
builder.append(cal.get(Calendar.DAY_OF_MONTH));
digits = 2;
break;
case 'e':
builder.append(cal.get(Calendar.DAY_OF_MONTH));
break;
case 'R':
singleDateTimeConversion(builder, cal, 'H', syms);
builder.append(':');
singleDateTimeConversion(builder, cal, 'M', syms);
break;
case 'T':
singleDateTimeConversion(builder, cal, 'H', syms);
builder.append(':');
singleDateTimeConversion(builder, cal, 'M', syms);
builder.append(':');
singleDateTimeConversion(builder, cal, 'S', syms);
break;
case 'r':
singleDateTimeConversion(builder, cal, 'I', syms);
builder.append(':');
singleDateTimeConversion(builder, cal, 'M', syms);
builder.append(':');
singleDateTimeConversion(builder, cal, 'S', syms);
builder.append(' ');
singleDateTimeConversion(builder, cal, 'p', syms);
break;
case 'D':
singleDateTimeConversion(builder, cal, 'm', syms);
builder.append('/');
singleDateTimeConversion(builder, cal, 'd', syms);
builder.append('/');
singleDateTimeConversion(builder, cal, 'y', syms);
break;
case 'F':
singleDateTimeConversion(builder, cal, 'Y', syms);
builder.append('-');
singleDateTimeConversion(builder, cal, 'm', syms);
builder.append('-');
singleDateTimeConversion(builder, cal, 'd', syms);
break;
case 'c':
singleDateTimeConversion(builder, cal, 'a', syms);
builder.append(' ');
singleDateTimeConversion(builder, cal, 'b', syms);
builder.append(' ');
singleDateTimeConversion(builder, cal, 'd', syms);
builder.append(' ');
singleDateTimeConversion(builder, cal, 'T', syms);
builder.append(' ');
singleDateTimeConversion(builder, cal, 'Z', syms);
builder.append(' ');
singleDateTimeConversion(builder, cal, 'Y', syms);
break;
default:
throw new UnknownFormatConversionException(String.valueOf(conversion));
}
if (digits > 0)
{
int newLen = builder.length();
int delta = newLen - oldLen;
while (delta++ < digits)
builder.insert(oldLen, '0');
}
}
/**
* Emit a date or time value.
*
* @param arg the date or time value.
* @param flags the formatting flags to use.
* @param width the width to use.
* @param precision the precision to use.
* @param conversion the conversion character.
* @param subConversion the sub conversion character.
* @throws IOException if the output stream throws an I/O error.
*/
private void dateTimeConversion(Object arg, int flags, int width,
int precision, char conversion,
char subConversion)
throws IOException
{
noPrecision(precision);
checkFlags(flags,
FormattableFlags.LEFT_JUSTIFY | FormattableFlags.UPPERCASE,
conversion);
Calendar cal;
if (arg instanceof Calendar)
cal = (Calendar) arg;
else
{
Date date;
if (arg instanceof Date)
date = (Date) arg;
else if (arg instanceof Long)
date = new Date(((Long) arg).longValue());
else
throw new IllegalFormatConversionException(conversion,
arg.getClass());
if (fmtLocale == null)
cal = Calendar.getInstance();
else
cal = Calendar.getInstance(fmtLocale);
cal.setTime(date);
}
// We could try to be more efficient by computing this lazily.
DateFormatSymbols syms;
if (fmtLocale == null)
syms = new DateFormatSymbols();
else
syms = new DateFormatSymbols(fmtLocale);
CPStringBuilder result = new CPStringBuilder();
singleDateTimeConversion(result, cal, subConversion, syms);
genericFormat(result.toString(), flags, width, precision);
}
/**
* Advance the internal parsing index, and throw an exception
* on overrun.
*
* @throws IllegalArgumentException on overrun.
*/
private void advance()
{
++index;
if (index >= length)
{
// FIXME: what exception here?
throw new IllegalArgumentException();
}
}
/**
* Parse an integer appearing in the format string. Will return -1
* if no integer was found.
*
* @return the parsed integer.
*/
private int parseInt()
{
int start = index;
while (Character.isDigit(format.charAt(index)))
advance();
if (start == index)
return -1;
return Integer.decode(format.substring(start, index));
}
/**
* Parse the argument index. Returns -1 if there was no index, 0 if
* we should re-use the previous index, and a positive integer to
* indicate an absolute index.
*
* @return the parsed argument index.
*/
private int parseArgumentIndex()
{
int result = -1;
int start = index;
if (format.charAt(index) == '<')
{
result = 0;
advance();
}
else if (Character.isDigit(format.charAt(index)))
{
result = parseInt();
if (format.charAt(index) == '$')
advance();
else
{
// Reset.
index = start;
result = -1;
}
}
return result;
}
/**
* Parse a set of flags and return a bit mask of values from
* FormattableFlags. Will throw an exception if a flag is
* duplicated.
*
* @return the parsed flags.
*/
private int parseFlags()
{
int value = 0;
int start = index;
while (true)
{
int x = FLAGS.indexOf(format.charAt(index));
if (x == -1)
break;
int newValue = 1 << x;
if ((value & newValue) != 0)
throw new DuplicateFormatFlagsException(format.substring(start,
index + 1));
value |= newValue;
advance();
}
return value;
}
/**
* Parse the width part of a format string. Returns -1 if no width
* was specified.
*
* @return the parsed width.
*/
private int parseWidth()
{
return parseInt();
}
/**
* If the current character is '.', parses the precision part of a
* format string. Returns -1 if no precision was specified.
*
* @return the parsed precision.
*/
private int parsePrecision()
{
if (format.charAt(index) != '.')
return -1;
advance();
int precision = parseInt();
if (precision == -1)
// FIXME
throw new IllegalArgumentException();
return precision;
}
/**
* Outputs a formatted string based on the supplied specification,
* fmt, and its arguments using the specified locale.
* The locale of the formatter does not change as a result; the
* specified locale is just used for this particular formatting
* operation. If the locale is null, then no
* localization is applied.
*
* @param loc the locale to use for this format.
* @param fmt the format specification.
* @param args the arguments to apply to the specification.
* @throws IllegalFormatException if there is a problem with
* the syntax of the format
* specification or a mismatch
* between it and the arguments.
* @throws FormatterClosedException if the formatter is closed.
*/
public Formatter format(Locale loc, String fmt, Object... args)
{
if (closed)
throw new FormatterClosedException();
// Note the arguments are indexed starting at 1.
int implicitArgumentIndex = 1;
int previousArgumentIndex = 0;
try
{
fmtLocale = loc;
format = fmt;
length = format.length();
for (index = 0; index < length; ++index)
{
char c = format.charAt(index);
if (c != '%')
{
out.append(c);
continue;
}
int start = index;
advance();
// We do the needed post-processing of this later, when we
// determine whether an argument is actually needed by
// this conversion.
int argumentIndex = parseArgumentIndex();
int flags = parseFlags();
int width = parseWidth();
int precision = parsePrecision();
char origConversion = format.charAt(index);
char conversion = origConversion;
if (Character.isUpperCase(conversion))
{
flags |= FormattableFlags.UPPERCASE;
conversion = Character.toLowerCase(conversion);
}
Object argument = null;
if (conversion == '%' || conversion == 'n')
{
if (argumentIndex != -1)
{
// FIXME: not sure about this.
throw new UnknownFormatConversionException("FIXME");
}
}
else
{
if (argumentIndex == -1)
argumentIndex = implicitArgumentIndex++;
else if (argumentIndex == 0)
argumentIndex = previousArgumentIndex;
// Argument indices start at 1 but array indices at 0.
--argumentIndex;
if (argumentIndex < 0 || argumentIndex >= args.length)
throw new MissingFormatArgumentException(format.substring(start, index));
argument = args[argumentIndex];
}
switch (conversion)
{
case 'b':
booleanFormat(argument, flags, width, precision,
origConversion);
break;
case 'h':
hashCodeFormat(argument, flags, width, precision,
origConversion);
break;
case 's':
stringFormat(argument, flags, width, precision,
origConversion);
break;
case 'c':
characterFormat(argument, flags, width, precision,
origConversion);
break;
case 'd':
checkFlags(flags & FormattableFlags.UPPERCASE, 0, 'd');
decimalConversion(argument, flags, width, precision,
origConversion);
break;
case 'o':
checkFlags(flags & FormattableFlags.UPPERCASE, 0, 'o');
hexOrOctalConversion(argument, flags, width, precision, 8,
origConversion);
break;
case 'x':
hexOrOctalConversion(argument, flags, width, precision, 16,
origConversion);
case 'e':
// scientificNotationConversion();
break;
case 'f':
// floatingDecimalConversion();
break;
case 'g':
// smartFloatingConversion();
break;
case 'a':
// hexFloatingConversion();
break;
case 't':
advance();
char subConversion = format.charAt(index);
dateTimeConversion(argument, flags, width, precision,
origConversion, subConversion);
break;
case '%':
percentFormat(flags, width, precision);
break;
case 'n':
newLineFormat(flags, width, precision);
break;
default:
throw new UnknownFormatConversionException(String.valueOf(origConversion));
}
}
}
catch (IOException exc)
{
ioException = exc;
}
return this;
}
/**
* Outputs a formatted string based on the supplied specification,
* fmt, and its arguments using the formatter's locale.
*
* @param format the format specification.
* @param args the arguments to apply to the specification.
* @throws IllegalFormatException if there is a problem with
* the syntax of the format
* specification or a mismatch
* between it and the arguments.
* @throws FormatterClosedException if the formatter is closed.
*/
public Formatter format(String format, Object... args)
{
return format(locale, format, args);
}
/**
* Returns the last I/O exception thrown by the
* append() operation of the underlying
* output stream.
*
* @return the last I/O exception.
*/
public IOException ioException()
{
return ioException;
}
/**
* Returns the locale used by this formatter.
*
* @return the formatter's locale.
* @throws FormatterClosedException if the formatter is closed.
*/
public Locale locale()
{
if (closed)
throw new FormatterClosedException();
return locale;
}
/**
* Returns the output stream used by this formatter.
*
* @return the formatter's output stream.
* @throws FormatterClosedException if the formatter is closed.
*/
public Appendable out()
{
if (closed)
throw new FormatterClosedException();
return out;
}
/**
* Returns the result of applying {@link Object#toString()}
* to the underlying output stream. The results returned
* depend on the particular {@link Appendable} being used.
* For example, a {@link StringBuilder} will return the
* formatted output but an I/O stream will not.
*
* @throws FormatterClosedException if the formatter is closed.
*/
public String toString()
{
if (closed)
throw new FormatterClosedException();
return out.toString();
}
}