Message Formatting Examples
Contents
MessageFormat Class
ICU’s MessageFormat class can be used to format messages in a locale-independent manner to localize the user interface (UI) strings.
C++
/* The strings below can be isolated into a resource bundle
* and retrieved dynamically
*/
#define LANGUAGE_NAMES "{0}<{1}languages {2}>\n"
#define LANG_ATTRIB "{0}<language id=\"{1}\" >{2}</language>\n"
#define MONTH_NAMES "{0}<monthNames>\n"
#define END_MONTH_NAMES "{0}</monthNames>\n"
#define MONTH "{0}<month id=\"{1}\">{2}</month>\n"
#define MONTH_ABBR "{0}<monthAbbr>\n"
#define END_MONTH_ABBR "{0}</monthAbbr>\n"
UnicodeString CXMLGenerator::formatString(UnicodeString& str,UnicodeString&
argument){
Formattable args[] ={ argument};
UnicodeString result;
MessageFormat format(str,mError);
FieldPosition fpos=0;
format.format(args,1, result,fpos,mError);
if(U_FAILURE(mError)) {
return UnicodeString("Illegal argument");
}
return result;
}
void CXMLGenerator::writeLanguage(UnicodeString& xmlString){
UnicodeString *itemTags, *items;
char* key="Languages";
int32_t numItems;
if(U_FAILURE(mError)) {
return;
}
mRBundle.getTaggedArray(key,itemTags, items, numItems, mError);
if(mError!=U_USING_DEFAULT_ERROR && U_SUCCESS(mError) &&
mError!=U_ERROR_INFO_START){
Formattable args[]={indentOffset,"",""};
xmlString= formatString(UnicodeString(LANGUAGE_NAMES),args,3);
indentOffset.append("\t");
for(int32_t i=0;i<numItems;i++){
args[0] = indentOffset;
args[1] =itemTags[i] ;
args[2] = items[i] ;
xmlString.append(formatString(UnicodeString(LANG_ATTRIB),args,3));
}
chopIndent();
args[0]=indentOffset;
args[1] =(UnicodeString(XML_END_SLASH));
args[2] = "";
xmlString.append(formatString(UnicodeString(LANGUAGE_NAMES),args,3));
return;
}
mError=U_ZERO_ERROR;
xmlString.remove();
}
void CXMLGenerator::writeMonthNames(UnicodeString& xmlString){
int32_t lNum;
const UnicodeString* longMonths=
mRBundle.getStringArray("MonthNames",lNum,mError);
if(mError!=U_USING_DEFAULT_ERROR && mError!=U_ERROR_INFO_START && mError !=
U_MISSING_RESOURCE_ERROR){
xmlString.append(formatString(UnicodeString(MONTH_NAMES),indentOffset));
indentOffset.append("\t");
for(int i=0;i<lNum;i++){
char c;
itoa(i+1,&c,10);
Formattable args[]={indentOffset,UnicodeString(&c),longMonths[i]};
xmlString.append(formatString(UnicodeString(MONTH),args,3));
}
chopIndent();
xmlString.append(formatString(UnicodeString(END_MONTH_NAMES),indentOffset));
mError=U_ZERO_ERROR;
return;
}
xmlString.remove();
mError= U_ZERO_ERROR;
}
C
void msgSample1(){
UChar *result, *tzID, *str;
UChar pattern[100];
int32_t resultLengthOut, resultlength;
UCalendar *cal;
UDate d1;
UErrorCode status = U_ZERO_ERROR;
str=(UChar*)malloc(sizeof(UChar) * (strlen("disturbance in force") +1));
u_uastrcpy(str, "disturbance in force");
tzID=(UChar*)malloc(sizeof(UChar) * 4);
u_uastrcpy(tzID, "PST");
cal=ucal_open(tzID, u_strlen(tzID), "en_US", UCAL_TRADITIONAL, &status);
ucal_setDateTime(cal, 1999, UCAL_MARCH, 18, 0, 0, 0, &status);
d1=ucal_getMillis(cal, &status);
u_uastrcpy(pattern, "On {0, date, long}, there was a {1} on planet
{2,number,integer}");
resultlength=0;
resultLengthOut=u_formatMessage( "en_US", pattern, u_strlen(pattern),
NULL,
resultlength, &status, d1, str, 7);
if(status==U_BUFFER_OVERFLOW_ERROR){
status=U_ZERO_ERROR;
resultlength=resultLengthOut+1;
result=(UChar*)realloc(result, sizeof(UChar) * resultlength);
u_formatMessage( "en_US", pattern, u_strlen(pattern), result,
resultlength, &status, d1, str, 7);
}
printf("%s\n",austrdup(result) ); //austrdup( a function used to convert
UChar* to char*)
free(tzID);
free(str);
free(result);
}
char *austrdup(const UChar* unichars)
{
int length;
char *newString;
length = u_strlen ( unichars );
newString = (char*)malloc ( sizeof( char ) * 4 * ( length + 1 ) );
if ( newString == NULL )
return NULL;
u_austrcpy ( newString, unichars );
return newString;
}
This is a more practical sample which retrieves data from a resource bundle
and
feeds the data
to u_formatMessage to produce a formatted string
void msgSample3(){
char* key="Languages";
int32_t numItems;
/* This constant string can also be in the resouce bundle and retrieved at
the time
* of formatting
* eg:
* UResouceBundle* myResB = ures_open("myResources",currentLocale,&err);
* UChar* Lang_Attrib = ures_getString(myResb,"LANG_ATTRIB",&err);
*/
UChar* LANG_ATTRIB =(UChar*) "{0}<language id=\"{1}\"
>{2}</language>\n";
UChar *result;
UResourceBundle* pResB,*pDeltaResB=NULL;
UErrorCode err=U_ZERO_ERROR;
UChar* indentOffset = (UChar*)"\t\t\t";
pResB = ures_open("","en",&err);
if(U_FAILURE(err)) {
return;
}
ures_getByKey(pResB, key, pDeltaResB, &err);
if(U_SUCCESS(err)) {
const UChar *value = 0;
const char *key = 0;
int32_t len = 0;
int16_t indexR = -1;
int32_t resultLength=0,resultLengthOut=0;
numItems = ures_getSize(pDeltaResB);
for(;numItems-->0;){
key= ures_getKey(pDeltaResB);
value = ures_get(pDeltaResB,key,&err);
resultLength=0;
resultLengthOut=u_formatMessage( "en_US", LANG_ATTRIB,
u_strlen(LANG_ATTRIB),
NULL, resultLength, &err,
indentOffset, value, key);
if(err==U_BUFFER_OVERFLOW_ERROR){
err=U_ZERO_ERROR;
resultLength=resultLengthOut+1;
result=(UChar*)realloc(result, sizeof(UChar) * resultLength);
u_formatMessage("en_US",LANG_ATTRIB,u_strlen(LANG_ATTRIB),
result,resultLength,&err,indentOffset,
value,key);
printf("%s\n", austrdup(result) );
}
}
return;
}
err=U_ZERO_ERROR;
}
Java
import com.ibm.icu.text.*;
import java.util.Date;
import java.text.FieldPosition;
public class TestMessageFormat{
public void runTest() {
String format = "At {1,time,::jmm} on {1,date,::dMMMM}, there was {2} on planet {3,number,integer}.";
MessageFormat mf = new MessageFormat(format);
Object objectsToFormat[] = { new Date(System.currentTimeMillis()), new Date(System.currentTimeMillis()), "a Disturbance in the Force", new Integer(5)};
FieldPosition fp = new FieldPosition(1);
StringBuffer sb = new StringBuffer();
try{
sb = mf.format(objectsToFormat, sb, fp);
System.out.println(sb.toString());
}catch(IllegalArgumentException e){
System.out.println("Exception during formatting of type :" +e);
}
}
public static void main(String args[]){
try{
new TestMessageFormat().runTest();
}catch(Exception e){
System.out.println("Exception of type: "+e);
}
}
}
ChoiceFormat Class
Important: The following documentation is outdated. ChoiceFormat is probably not what you need. Please use MessageFormat with plural arguments for proper plural selection, and select arguments for simple selection among a fixed set of choices!
ICU’s ChoiceFormat class provides more flexibility than the printf() and scanf() style functions for formatting UI strings. This interface can be useful if you would like a message to change according to the number of items you are displaying.
Note: Some Asian languages do not have plural words or phrases.
C++
void msgSample1(){
UChar *result, *tzID, *str;
UChar pattern[100];
int32_t resultLengthOut, resultlength;
UCalendar *cal;
UDate d1;
UErrorCode status = U_ZERO_ERROR;
str=(UChar*)malloc(sizeof(UChar) * (strlen("disturbance in force") +1));
u_uastrcpy(str, "disturbance in force");
tzID=(UChar*)malloc(sizeof(UChar) * 4);
u_uastrcpy(tzID, "PST");
cal=ucal_open(tzID, u_strlen(tzID), "en_US", UCAL_TRADITIONAL, &status);
ucal_setDateTime(cal, 1999, UCAL_MARCH, 18, 0, 0, 0, &status);
d1=ucal_getMillis(cal, &status);
u_uastrcpy(pattern, "On {0, date, long}, there was a {1} on planet
{2,number,integer}");
resultlength=0;
resultLengthOut=u_formatMessage( "en_US", pattern, u_strlen(pattern),
NULL,
resultlength, &status, d1, str, 7);
if(status==U_BUFFER_OVERFLOW_ERROR){
status=U_ZERO_ERROR;
resultlength=resultLengthOut+1;
result=(UChar*)realloc(result, sizeof(UChar) * resultlength);
u_formatMessage( "en_US", pattern, u_strlen(pattern), result,
resultlength, &status, d1, str, 7);
}
printf("%s\n",austrdup(result) ); //austrdup( a function used to convert
UChar* to char*)
free(tzID);
free(str);
double filelimits[] = {0,1,2};
UErrorCode err;
UnicodeString filepart[] = {"are no files","is one file","are {2} files"};
ChoiceFormat fileform(filelimits, filepart,err);
Format testFormats[] = {fileform, null, NumberFormat.getInstance()};
MessageFormat pattform("There {0} on {1}",err);
pattform.setFormats(testFormats);
Formattable testArgs[] = {null, "ADisk", null};
for (int i = 0; i < 4; ++i) {
testArgs[0] = i;
testArgs[2] = testArgs[0];
FieldPosition fpos=0;
format.format(args,1, result,fpos,mError);
UnicodeString result = pattform.format(testArgs);
}
C
void msgSample2(){
UChar* str;
UErrorCode status = U_ZERO_ERROR;
UChar *result;
UChar pattern[100];
int32_t resultlength,resultLengthOut, i;
double testArgs[3]= { 100.0, 1.0, 0.0};
str=(UChar*)malloc(sizeof(UChar) * 10);
u_uastrcpy(str, "MyDisk");
u_uastrcpy(pattern, "The disk {1} contains {0,choice,0#no files|1#one
file|1<{0,number,integer} files}");
for(i=0; i<3; i++){
resultlength=0;
resultLengthOut=u_formatMessage( "en_US", pattern, u_strlen(pattern),
NULL, resultlength, &status, testArgs[i], str);
if(status==U_BUFFER_OVERFLOW_ERROR){
status=U_ZERO_ERROR;
resultlength=resultLengthOut+1;
result=(UChar*)malloc(sizeof(UChar) * resultlength);
u_formatMessage( "en_US", pattern, u_strlen(pattern), result,
resultlength, &status, testArgs[i], str);
}
}
printf("%s\n", austrdup(result) ); //austrdup( a function used to
convert
UChar* to char*)
free(result);
}
Java
import java.text.ChoiceFormat;
import com.ibm.icu.text.*;
import java.text.Format;
public class TestChoiceFormat{
public void run(){
double[] filelimits = {0,1,2};
String[] filepart = {"are no files","is one file","are {2} files"};
ChoiceFormat fileform = new ChoiceFormat(filelimits,filepart);
Format[] testFormats = {fileform,null,NumberFormat.getInstance()};
MessageFormat pattform = new MessageFormat("There {0} on {1}");
Object[] testArgs = {null,"ADisk",null};
for(int i=0;i<4;++i) {
testArgs[0] = new Integer(i);
testArgs[2] = testArgs[0];
System.out.println(pattform.format(testArgs));
}
}
public static void main(String args[]){
new TestChoiceFormat().run();
}
}