gcc/libjava/java/text/MessageFormat.java

545 lines
14 KiB
Java

// MessageFormat.java - Localized message formatting.
/* Copyright (C) 1999 Red Hat, Inc.
This file is part of libgcj.
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.text;
import java.util.Date;
import java.util.Locale;
import java.util.Vector;
/**
* @author Tom Tromey <tromey@cygnus.com>
* @date March 3, 1999
*/
/* Written using "Java Class Libraries", 2nd edition, plus online
* API docs for JDK 1.2 from http://www.javasoft.com.
* Status: Believed complete and correct to 1.2, except serialization.
* and parsing.
*/
final class MessageFormatElement
{
// Argument number.
int argNumber;
// Formatter to be used. This is the format set by setFormat.
Format setFormat;
// Formatter to be used based on the type.
Format format;
// Argument will be checked to make sure it is an instance of this
// class.
Class formatClass;
// Formatter type.
String type;
// Formatter style.
String style;
// Text to follow this element.
String trailer;
// FIXME: shouldn't need this.
Class forName (String name)
{
try
{
return Class.forName (name);
}
catch (ClassNotFoundException x)
{
}
return null;
}
// Recompute the locale-based formatter.
void setLocale (Locale loc)
{
if (type == null)
;
else if (type.equals("number"))
{
// FIXME: named class literal.
// formatClass = Number.class;
formatClass = forName ("java.lang.Number");
if (style == null)
format = NumberFormat.getInstance(loc);
else if (style.equals("currency"))
format = NumberFormat.getCurrencyInstance(loc);
else if (style.equals("percent"))
format = NumberFormat.getPercentInstance(loc);
else if (style.equals("integer"))
{
NumberFormat nf = NumberFormat.getNumberInstance(loc);
nf.setMaximumFractionDigits(0);
nf.setGroupingUsed(false);
format = nf;
}
else
{
format = NumberFormat.getNumberInstance(loc);
DecimalFormat df = (DecimalFormat) format;
try
{
df.applyPattern(style);
}
catch (ParseException x)
{
throw new IllegalArgumentException (x.getMessage());
}
}
}
else if (type.equals("time") || type.equals("date"))
{
// FIXME: named class literal.
// formatClass = Date.class;
formatClass = forName ("java.util.Date");
int val = DateFormat.DEFAULT;
if (style == null)
;
if (style.equals("short"))
val = DateFormat.SHORT;
else if (style.equals("medium"))
val = DateFormat.MEDIUM;
else if (style.equals("long"))
val = DateFormat.LONG;
else if (style.equals("full"))
val = DateFormat.FULL;
if (type.equals("time"))
format = DateFormat.getTimeInstance(val, loc);
else
format = DateFormat.getDateInstance(val, loc);
if (style != null && val == DateFormat.DEFAULT)
{
SimpleDateFormat sdf = (SimpleDateFormat) format;
sdf.applyPattern(style);
}
}
else if (type.equals("choice"))
{
// FIXME: named class literal.
// formatClass = Number.class;
formatClass = forName ("java.lang.Number");
if (style == null)
throw new
IllegalArgumentException ("style required for choice format");
format = new ChoiceFormat (style);
}
}
}
public class MessageFormat extends Format
{
// Helper that returns the text up to the next format opener. The
// text is put into BUFFER. Returns index of character after end of
// string. Throws IllegalArgumentException on error.
private static final int scanString (String pat, int index,
StringBuffer buffer)
{
int max = pat.length();
buffer.setLength(0);
for (; index < max; ++index)
{
char c = pat.charAt(index);
if (c == '\'' && index + 2 < max && pat.charAt(index + 2) == '\'')
{
buffer.append(pat.charAt(index + 1));
index += 2;
}
else if (c == '\'' && index + 1 < max
&& pat.charAt(index + 1) == '\'')
{
buffer.append(c);
++index;
}
else if (c == '{')
break;
else if (c == '}')
throw new IllegalArgumentException ();
else
buffer.append(c);
}
return index;
}
// This helper retrieves a single part of a format element. Returns
// the index of the terminating character.
private static final int scanFormatElement (String pat, int index,
StringBuffer buffer,
char term)
{
int max = pat.length();
buffer.setLength(0);
int brace_depth = 1;
for (; index < max; ++index)
{
char c = pat.charAt(index);
if (c == '\'' && index + 2 < max && pat.charAt(index + 2) == '\'')
{
buffer.append(c);
buffer.append(pat.charAt(index + 1));
buffer.append(c);
index += 2;
}
else if (c == '\'' && index + 1 < max
&& pat.charAt(index + 1) == '\'')
{
buffer.append(c);
++index;
}
else if (c == '{')
{
buffer.append(c);
++brace_depth;
}
else if (c == '}')
{
if (--brace_depth == 0)
break;
buffer.append(c);
}
// Check for TERM after braces, because TERM might be `}'.
else if (c == term)
break;
else
buffer.append(c);
}
return index;
}
// This is used to parse a format element and whatever non-format
// text might trail it.
private static final int scanFormat (String pat, int index,
StringBuffer buffer, Vector elts,
Locale locale)
{
MessageFormatElement mfe = new MessageFormatElement ();
elts.addElement(mfe);
int max = pat.length();
// Skip the opening `{'.
++index;
// Fetch the argument number.
index = scanFormatElement (pat, index, buffer, ',');
try
{
mfe.argNumber = Integer.parseInt(buffer.toString());
}
catch (NumberFormatException nfx)
{
throw new IllegalArgumentException ();
}
// Extract the element format.
if (index < max && pat.charAt(index) == ',')
{
index = scanFormatElement (pat, index + 1, buffer, ',');
mfe.type = buffer.toString();
// Extract the style.
if (index < max && pat.charAt(index) == ',')
{
index = scanFormatElement (pat, index + 1, buffer, '}');
mfe.style = buffer.toString ();
}
}
// Advance past the last terminator.
if (index >= max || pat.charAt(index) != '}')
throw new IllegalArgumentException ();
++index;
// Now fetch trailing string.
index = scanString (pat, index, buffer);
mfe.trailer = buffer.toString ();
mfe.setLocale(locale);
return index;
}
public void applyPattern (String newPattern)
{
pattern = newPattern;
StringBuffer tempBuffer = new StringBuffer ();
int index = scanString (newPattern, 0, tempBuffer);
leader = tempBuffer.toString();
Vector elts = new Vector ();
while (index < newPattern.length())
index = scanFormat (newPattern, index, tempBuffer, elts, locale);
elements = new MessageFormatElement[elts.size()];
elts.copyInto(elements);
}
public Object clone ()
{
MessageFormat c = new MessageFormat ();
c.setLocale(locale);
c.applyPattern(pattern);
return (Object) c;
}
public boolean equals (Object obj)
{
if (! (obj instanceof MessageFormat))
return false;
MessageFormat mf = (MessageFormat) obj;
return (pattern.equals(mf.pattern)
&& locale.equals(mf.locale));
}
public static String format (String pattern, Object arguments[])
{
MessageFormat mf = new MessageFormat (pattern);
StringBuffer sb = new StringBuffer ();
FieldPosition fp = new FieldPosition (NumberFormat.INTEGER_FIELD);
return mf.format(arguments, sb, fp).toString();
}
public final StringBuffer format (Object arguments[], StringBuffer appendBuf,
FieldPosition ignore)
{
appendBuf.append(leader);
for (int i = 0; i < elements.length; ++i)
{
if (elements[i].argNumber >= arguments.length)
throw new IllegalArgumentException ();
Object thisArg = arguments[elements[i].argNumber];
Format formatter = null;
if (elements[i].setFormat != null)
formatter = elements[i].setFormat;
else if (elements[i].format != null)
{
if (elements[i].formatClass != null
&& ! elements[i].formatClass.isInstance(thisArg))
throw new IllegalArgumentException ();
formatter = elements[i].format;
}
else if (thisArg instanceof Number)
formatter = NumberFormat.getInstance(locale);
else if (thisArg instanceof Date)
formatter = DateFormat.getTimeInstance(DateFormat.DEFAULT, locale);
else
appendBuf.append(thisArg);
if (formatter != null)
{
// Special-case ChoiceFormat.
if (formatter instanceof ChoiceFormat)
{
StringBuffer buf = new StringBuffer ();
// FIXME: don't actually know what is correct here.
// Can a sub-format refer to any argument, or just
// the single argument passed to it? Must test
// against JDK.
formatter.format(thisArg, buf, ignore);
MessageFormat mf = new MessageFormat ();
mf.setLocale(locale);
mf.applyPattern(buf.toString());
formatter = mf;
}
formatter.format(thisArg, appendBuf, ignore);
}
appendBuf.append(elements[i].trailer);
}
return appendBuf;
}
public final StringBuffer format (Object singleArg, StringBuffer appendBuf,
FieldPosition ignore)
{
Object[] args = new Object[1];
args[0] = singleArg;
return format (args, appendBuf, ignore);
}
public Format[] getFormats ()
{
Format[] f = new Format[elements.length];
for (int i = elements.length - 1; i >= 0; --i)
f[i] = elements[i].setFormat;
return f;
}
public Locale getLocale ()
{
return locale;
}
public int hashCode ()
{
// FIXME: not a very good hash.
return pattern.hashCode() + locale.hashCode();
}
private MessageFormat ()
{
}
public MessageFormat (String pattern)
{
locale = Locale.getDefault();
applyPattern (pattern);
}
public Object[] parse (String sourceStr, ParsePosition pos)
{
// Check initial text.
int index = pos.getIndex();
if (! sourceStr.startsWith(leader, index))
{
pos.setErrorIndex(index);
return null;
}
index += leader.length();
Vector results = new Vector (elements.length, 1);
// Now check each format.
for (int i = 0; i < elements.length; ++i)
{
Format formatter = null;
if (elements[i].setFormat != null)
formatter = elements[i].setFormat;
else if (elements[i].format != null)
formatter = elements[i].format;
Object value = null;
if (formatter instanceof ChoiceFormat)
{
// We must special-case a ChoiceFormat because it might
// have recursive formatting.
ChoiceFormat cf = (ChoiceFormat) formatter;
String[] formats = (String[]) cf.getFormats();
double[] limits = (double[]) cf.getLimits();
MessageFormat subfmt = new MessageFormat ();
subfmt.setLocale(locale);
ParsePosition subpos = new ParsePosition (index);
int j;
for (j = 0; value == null && j < limits.length; ++j)
{
subfmt.applyPattern(formats[j]);
subpos.setIndex(index);
value = subfmt.parse(sourceStr, subpos);
}
if (value != null)
{
index = subpos.getIndex();
value = new Double (limits[j]);
}
}
else if (formatter != null)
{
pos.setIndex(index);
value = formatter.parseObject(sourceStr, pos);
if (value != null)
index = pos.getIndex();
}
else
{
// We have a String format. This can lose in a number
// of ways, but we give it a shot.
int next_index = sourceStr.indexOf(elements[i].trailer, index);
if (next_index == -1)
{
pos.setErrorIndex(index);
return null;
}
value = sourceStr.substring(index, next_index);
index = next_index;
}
if (value == null
|| ! sourceStr.startsWith(elements[i].trailer, index))
{
pos.setErrorIndex(index);
return null;
}
if (elements[i].argNumber >= results.size())
results.setSize(elements[i].argNumber + 1);
results.setElementAt(value, elements[i].argNumber);
index += elements[i].trailer.length();
}
Object[] r = new Object[results.size()];
results.copyInto(r);
return r;
}
public Object[] parse (String sourceStr) throws ParseException
{
ParsePosition pp = new ParsePosition (0);
Object[] r = parse (sourceStr, pp);
if (r == null)
throw new ParseException ("couldn't parse string", pp.getErrorIndex());
return r;
}
public Object parseObject (String sourceStr, ParsePosition pos)
{
return parse (sourceStr, pos);
}
public void setFormat (int variableNum, Format newFormat)
{
elements[variableNum].setFormat = newFormat;
}
public void setFormats (Format[] newFormats)
{
if (newFormats.length < elements.length)
throw new IllegalArgumentException ();
int len = Math.min(newFormats.length, elements.length);
for (int i = 0; i < len; ++i)
elements[i].setFormat = newFormats[i];
}
public void setLocale (Locale loc)
{
locale = loc;
if (elements != null)
{
for (int i = 0; i < elements.length; ++i)
elements[i].setLocale(loc);
}
}
public String toPattern ()
{
return pattern;
}
// The pattern string.
private String pattern;
// The locale.
private Locale locale;
// Variables.
private MessageFormatElement[] elements;
// Leader text.
private String leader;
}