com.ibm.icu.message2.MFDataModelFormatter Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of icu4j Show documentation
Show all versions of icu4j Show documentation
International Component for Unicode for Java (ICU4J) is a mature, widely used Java library
providing Unicode and Globalization support
The newest version!
// © 2022 and later: Unicode, Inc. and others.
// License & terms of use: https://www.unicode.org/copyright.html
package com.ibm.icu.message2;
import java.time.temporal.Temporal;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import com.ibm.icu.message2.MFDataModel.Annotation;
import com.ibm.icu.message2.MFDataModel.CatchallKey;
import com.ibm.icu.message2.MFDataModel.Declaration;
import com.ibm.icu.message2.MFDataModel.Expression;
import com.ibm.icu.message2.MFDataModel.FunctionAnnotation;
import com.ibm.icu.message2.MFDataModel.FunctionExpression;
import com.ibm.icu.message2.MFDataModel.InputDeclaration;
import com.ibm.icu.message2.MFDataModel.Literal;
import com.ibm.icu.message2.MFDataModel.LiteralExpression;
import com.ibm.icu.message2.MFDataModel.LiteralOrCatchallKey;
import com.ibm.icu.message2.MFDataModel.LiteralOrVariableRef;
import com.ibm.icu.message2.MFDataModel.LocalDeclaration;
import com.ibm.icu.message2.MFDataModel.Option;
import com.ibm.icu.message2.MFDataModel.Pattern;
import com.ibm.icu.message2.MFDataModel.SelectMessage;
import com.ibm.icu.message2.MFDataModel.StringPart;
import com.ibm.icu.message2.MFDataModel.VariableRef;
import com.ibm.icu.message2.MFDataModel.Variant;
import com.ibm.icu.message2.MessageFormatter.ErrorHandlingBehavior;
import com.ibm.icu.util.Calendar;
import com.ibm.icu.util.CurrencyAmount;
/**
* Takes an {@link MFDataModel} and formats it to a {@link String}
* (and later on we will also implement formatting to a {@code FormattedMessage}).
*/
// TODO: move this in the MessageFormatter?
class MFDataModelFormatter {
private final Locale locale;
private final ErrorHandlingBehavior errorHandlingBehavior;
private final MFDataModel.Message dm;
private final MFFunctionRegistry standardFunctions;
private final MFFunctionRegistry customFunctions;
private static final MFFunctionRegistry EMPTY_REGISTY = MFFunctionRegistry.builder().build();
MFDataModelFormatter(
MFDataModel.Message dm,
Locale locale,
ErrorHandlingBehavior errorHandlingBehavior,
MFFunctionRegistry customFunctionRegistry) {
this.locale = locale;
this.errorHandlingBehavior = errorHandlingBehavior == null
? ErrorHandlingBehavior.BEST_EFFORT : errorHandlingBehavior;
this.dm = dm;
this.customFunctions =
customFunctionRegistry == null ? EMPTY_REGISTY : customFunctionRegistry;
standardFunctions =
MFFunctionRegistry.builder()
// Date/time formatting
.setFormatter("datetime", new DateTimeFormatterFactory("datetime"))
.setFormatter("date", new DateTimeFormatterFactory("date"))
.setFormatter("time", new DateTimeFormatterFactory("time"))
.setDefaultFormatterNameForType(Date.class, "datetime")
.setDefaultFormatterNameForType(Calendar.class, "datetime")
.setDefaultFormatterNameForType(java.util.Calendar.class, "datetime")
.setDefaultFormatterNameForType(Temporal.class, "datetime")
// Number formatting
.setFormatter("number", new NumberFormatterFactory("number"))
.setFormatter("integer", new NumberFormatterFactory("integer"))
.setDefaultFormatterNameForType(Integer.class, "number")
.setDefaultFormatterNameForType(Double.class, "number")
.setDefaultFormatterNameForType(Number.class, "number")
.setDefaultFormatterNameForType(CurrencyAmount.class, "number")
// Format that returns "to string"
.setFormatter("string", new IdentityFormatterFactory())
.setDefaultFormatterNameForType(String.class, "string")
.setDefaultFormatterNameForType(CharSequence.class, "string")
// Register the standard selectors
.setSelector("number", new NumberFormatterFactory("number"))
.setSelector("integer", new NumberFormatterFactory("integer"))
.setSelector("string", new TextSelectorFactory())
.setSelector("icu:gender", new TextSelectorFactory())
.build();
}
String format(Map arguments) {
MFDataModel.Pattern patternToRender = null;
if (arguments == null) {
arguments = new HashMap<>();
}
Map variables;
if (dm instanceof MFDataModel.PatternMessage) {
MFDataModel.PatternMessage pm = (MFDataModel.PatternMessage) dm;
variables = resolveDeclarations(pm.declarations, arguments);
if (pm.pattern == null) {
fatalFormattingError("The PatternMessage is null.");
}
patternToRender = pm.pattern;
} else if (dm instanceof MFDataModel.SelectMessage) {
MFDataModel.SelectMessage sm = (MFDataModel.SelectMessage) dm;
variables = resolveDeclarations(sm.declarations, arguments);
patternToRender = findBestMatchingPattern(sm, variables, arguments);
if (patternToRender == null) {
fatalFormattingError("Cannor find a match for the selector.");
}
} else {
fatalFormattingError("Unknown message type.");
// formattingError throws, so the return does not actually happen
return "ERROR!";
}
StringBuilder result = new StringBuilder();
for (MFDataModel.PatternPart part : patternToRender.parts) {
if (part instanceof MFDataModel.StringPart) {
MFDataModel.StringPart strPart = (StringPart) part;
result.append(strPart.value);
} else if (part instanceof MFDataModel.Expression) {
FormattedPlaceholder formattedExpression =
formatExpression((Expression) part, variables, arguments);
result.append(formattedExpression.getFormattedValue().toString());
} else if (part instanceof MFDataModel.Markup) {
// Ignore
} else {
fatalFormattingError("Unknown part type: " + part);
}
}
return result.toString();
}
private Pattern findBestMatchingPattern(
SelectMessage sm, Map variables, Map arguments) {
Pattern patternToRender = null;
// ====================================
// spec: ### Resolve Selectors
// ====================================
// Collect all the selector functions in an array, to reuse
List selectors = sm.selectors;
// spec: Let `res` be a new empty list of resolved values that support selection.
List res = new ArrayList<>(selectors.size());
// spec: For each _selector_ `sel`, in source order,
for (Expression sel : selectors) {
// spec: Let `rv` be the resolved value of `sel`.
FormattedPlaceholder fph = formatExpression(sel, variables, arguments);
String functionName = null;
Object argument = null;
Map options = new HashMap<>();
if (fph.getInput() instanceof ResolvedExpression) {
ResolvedExpression re = (ResolvedExpression) fph.getInput();
argument = re.argument;
functionName = re.functionName;
options.putAll(re.options);
} else if (fph.getInput() instanceof MFDataModel.VariableExpression) {
MFDataModel.VariableExpression ve = (MFDataModel.VariableExpression) fph.getInput();
argument = resolveLiteralOrVariable(ve.arg, variables, arguments);
if (ve.annotation instanceof FunctionAnnotation) {
functionName = ((FunctionAnnotation) ve.annotation).name;
}
} else if (fph.getInput() instanceof LiteralExpression) {
LiteralExpression le = (LiteralExpression) fph.getInput();
argument = le.arg;
if (le.annotation instanceof FunctionAnnotation) {
functionName = ((FunctionAnnotation) le.annotation).name;
}
}
SelectorFactory funcFactory = standardFunctions.getSelector(functionName);
if (funcFactory == null) {
funcFactory = customFunctions.getSelector(functionName);
}
// spec: If selection is supported for `rv`:
if (funcFactory != null) {
Selector selectorFunction = funcFactory.createSelector(locale, options);
ResolvedSelector rs = new ResolvedSelector(argument, options, selectorFunction);
// spec: Append `rv` as the last element of the list `res`.
res.add(rs);
} else {
fatalFormattingError("Unknown selector type: " + functionName);
}
}
// This should not be possible, we added one function for each selector,
// or we have thrown an exception.
// But just in case someone removes the throw above?
if (res.size() != selectors.size()) {
fatalFormattingError(
"Something went wrong, not enough selector functions, "
+ res.size() + " vs. " + selectors.size());
}
// ====================================
// spec: ### Resolve Preferences
// ====================================
// spec: Let `pref` be a new empty list of lists of strings.
List> pref = new ArrayList<>();
// spec: For each index `i` in `res`:
for (int i = 0; i < res.size(); i++) {
// spec: Let `keys` be a new empty list of strings.
List keys = new ArrayList<>();
// spec: For each _variant_ `var` of the message:
for (Variant var : sm.variants) {
// spec: Let `key` be the `var` key at position `i`.
LiteralOrCatchallKey key = var.keys.get(i);
// spec: If `key` is not the catch-all key `'*'`:
if (key instanceof CatchallKey) {
keys.add("*");
} else if (key instanceof Literal) {
// spec: Assert that `key` is a _literal_.
// spec: Let `ks` be the resolved value of `key`.
String ks = ((Literal) key).value;
// spec: Append `ks` as the last element of the list `keys`.
keys.add(ks);
} else {
fatalFormattingError("Literal expected, but got " + key);
}
}
// spec: Let `rv` be the resolved value at index `i` of `res`.
ResolvedSelector rv = res.get(i);
// spec: Let `matches` be the result of calling the method MatchSelectorKeys(`rv`, `keys`)
List matches = matchSelectorKeys(rv, keys);
// spec: Append `matches` as the last element of the list `pref`.
pref.add(matches);
}
// ====================================
// spec: ### Filter Variants
// ====================================
// spec: Let `vars` be a new empty list of _variants_.
List vars = new ArrayList<>();
// spec: For each _variant_ `var` of the message:
for (Variant var : sm.variants) {
// spec: For each index `i` in `pref`:
int found = 0;
for (int i = 0; i < pref.size(); i++) {
// spec: Let `key` be the `var` key at position `i`.
LiteralOrCatchallKey key = var.keys.get(i);
// spec: If `key` is the catch-all key `'*'`:
if (key instanceof CatchallKey) {
// spec: Continue the inner loop on `pref`.
found++;
continue;
}
// spec: Assert that `key` is a _literal_.
if (!(key instanceof Literal)) {
fatalFormattingError("Literal expected");
}
// spec: Let `ks` be the resolved value of `key`.
String ks = ((Literal) key).value;
// spec: Let `matches` be the list of strings at index `i` of `pref`.
List matches = pref.get(i);
// spec: If `matches` includes `ks`:
if (matches.contains(ks)) {
// spec: Continue the inner loop on `pref`.
found++;
continue;
} else {
// spec: Else:
// spec: Continue the outer loop on message _variants_.
break;
}
}
if (found == pref.size()) {
// spec: Append `var` as the last element of the list `vars`.
vars.add(var);
}
}
// ====================================
// spec: ### Sort Variants
// ====================================
// spec: Let `sortable` be a new empty list of (integer, _variant_) tuples.
List sortable = new ArrayList<>();
// spec: For each _variant_ `var` of `vars`:
for (Variant var : vars) {
// spec: Let `tuple` be a new tuple (-1, `var`).
IntVarTuple tuple = new IntVarTuple(-1, var);
// spec: Append `tuple` as the last element of the list `sortable`.
sortable.add(tuple);
}
// spec: Let `len` be the integer count of items in `pref`.
int len = pref.size();
// spec: Let `i` be `len` - 1.
int i = len - 1;
// spec: While `i` >= 0:
while (i >= 0) {
// spec: Let `matches` be the list of strings at index `i` of `pref`.
List matches = pref.get(i);
// spec: Let `minpref` be the integer count of items in `matches`.
int minpref = matches.size();
// spec: For each tuple `tuple` of `sortable`:
for (IntVarTuple tuple : sortable) {
// spec: Let `matchpref` be an integer with the value `minpref`.
int matchpref = minpref;
// spec: Let `key` be the `tuple` _variant_ key at position `i`.
LiteralOrCatchallKey key = tuple.variant.keys.get(i);
// spec: If `key` is not the catch-all key `'*'`:
if (!(key instanceof CatchallKey)) {
// spec: Assert that `key` is a _literal_.
if (!(key instanceof Literal)) {
fatalFormattingError("Literal expected");
}
// spec: Let `ks` be the resolved value of `key`.
String ks = ((Literal) key).value;
// spec: Let `matchpref` be the integer position of `ks` in `matches`.
matchpref = matches.indexOf(ks);
}
// spec: Set the `tuple` integer value as `matchpref`.
tuple.integer = matchpref;
}
// spec: Set `sortable` to be the result of calling the method `SortVariants(sortable)`.
sortable.sort(MFDataModelFormatter::sortVariants);
// spec: Set `i` to be `i` - 1.
i--;
}
// spec: Let `var` be the _variant_ element of the first element of `sortable`.
IntVarTuple var = sortable.get(0);
// spec: Select the _pattern_ of `var`.
patternToRender = var.variant.value;
// And should do that only once, when building the data model.
if (patternToRender == null) {
// If there was a case with all entries in the keys `*` this should not happen
fatalFormattingError("The selection went wrong, cannot select any option.");
}
return patternToRender;
}
/* spec:
* `SortVariants` is a method whose single argument is
* a list of (integer, _variant_) tuples.
* It returns a list of (integer, _variant_) tuples.
* Any implementation of `SortVariants` is acceptable
* as long as it satisfies the following requirements:
*
* 1. Let `sortable` be an arbitrary list of (integer, _variant_) tuples.
* 1. Let `sorted` be `SortVariants(sortable)`.
* 1. `sorted` is the result of sorting `sortable` using the following comparator:
* 1. `(i1, v1)` <= `(i2, v2)` if and only if `i1 <= i2`.
* 1. The sort is stable (pairs of tuples from `sortable` that are equal
* in their first element have the same relative order in `sorted`).
*/
private static int sortVariants(IntVarTuple o1, IntVarTuple o2) {
int result = Integer.compare(o1.integer, o2.integer);
if (result != 0) {
return result;
}
List v1 = o1.variant.keys;
List v2 = o1.variant.keys;
if (v1.size() != v2.size()) {
fatalFormattingError("The number of keys is not equal.");
}
for (int i = 0; i < v1.size(); i++) {
LiteralOrCatchallKey k1 = v1.get(i);
LiteralOrCatchallKey k2 = v2.get(i);
String s1 = k1 instanceof Literal ? ((Literal) k1).value : "*";
String s2 = k2 instanceof Literal ? ((Literal) k2).value : "*";
int cmp = s1.compareTo(s2);
if (cmp != 0) {
return cmp;
}
}
return 0;
}
/**
* spec:
* The method MatchSelectorKeys is determined by the implementation.
* It takes as arguments a resolved _selector_ value `rv` and a list of string keys `keys`,
* and returns a list of string keys in preferential order.
* The returned list MUST contain only unique elements of the input list `keys`.
* The returned list MAY be empty.
* The most-preferred key is first,
* with each successive key appearing in order by decreasing preference.
*/
@SuppressWarnings("static-method")
private List matchSelectorKeys(ResolvedSelector rv, List keys) {
return rv.selectorFunction.matches(rv.argument, keys, rv.options);
}
private static class ResolvedSelector {
final Object argument;
final Map options;
final Selector selectorFunction;
public ResolvedSelector(
Object argument, Map options, Selector selectorFunction) {
this.argument = argument;
this.options = new HashMap<>(options);
this.selectorFunction = selectorFunction;
}
}
private static void fatalFormattingError(String message) throws IllegalArgumentException {
throw new IllegalArgumentException(message);
}
private FormatterFactory getFormattingFunctionFactoryByName(
Object toFormat, String functionName) {
// Get a function name from the type of the object to format
if (functionName == null || functionName.isEmpty()) {
if (toFormat == null) {
// The object to format is null, and no function provided.
return null;
}
Class clazz = toFormat.getClass();
functionName = standardFunctions.getDefaultFormatterNameForType(clazz);
if (functionName == null) {
functionName = customFunctions.getDefaultFormatterNameForType(clazz);
}
if (functionName == null) {
fatalFormattingError(
"Object to format without a function, and unknown type: "
+ toFormat.getClass().getName());
}
}
FormatterFactory func = standardFunctions.getFormatter(functionName);
if (func == null) {
func = customFunctions.getFormatter(functionName);
}
return func;
}
private static Object resolveLiteralOrVariable(
LiteralOrVariableRef value,
Map localVars,
Map arguments) {
if (value instanceof Literal) {
String val = ((Literal) value).value;
// "The resolution of a text or literal MUST resolve to a string."
// https://github.com/unicode-org/message-format-wg/blob/main/spec/formatting.md#literal-resolution
return val;
} else if (value instanceof VariableRef) {
String varName = ((VariableRef) value).name;
Object val = localVars.get(varName);
if (val == null) {
val = localVars.get(varName);
}
if (val == null) {
val = arguments.get(varName);
}
return val;
}
return value;
}
private static Map convertOptions(
Map options,
Map localVars,
Map arguments) {
Map result = new HashMap<>();
for (Option option : options.values()) {
result.put(option.name, resolveLiteralOrVariable(option.value, localVars, arguments));
}
return result;
}
/**
* Formats an expression.
*
* @param expression the expression to format
* @param variables local variables, created from declarations (`.input` and `.local`)
* @param arguments the arguments passed at runtime to be formatted (`mf.format(arguments)`)
*/
private FormattedPlaceholder formatExpression(
Expression expression, Map variables, Map arguments) {
Annotation annotation = null; // function name
String functionName = null;
Object toFormat = null;
Map options = new HashMap<>();
String fallbackString = "{\uFFFD}";
if (expression instanceof MFDataModel.VariableExpression) {
MFDataModel.VariableExpression varPart = (MFDataModel.VariableExpression) expression;
fallbackString = "{$" + varPart.arg.name + "}";
annotation = varPart.annotation; // function name & options
Object resolved = resolveLiteralOrVariable(varPart.arg, variables, arguments);
if (resolved instanceof FormattedPlaceholder) {
Object input = ((FormattedPlaceholder) resolved).getInput();
if (input instanceof ResolvedExpression) {
ResolvedExpression re = (ResolvedExpression) input;
toFormat = re.argument;
functionName = re.functionName;
options.putAll(re.options);
} else {
toFormat = input;
}
} else {
toFormat = resolved;
}
} else if (expression
instanceof MFDataModel.FunctionExpression) { // Function without arguments
MFDataModel.FunctionExpression fe = (FunctionExpression) expression;
fallbackString = "{:" + fe.annotation.name + "}";
annotation = fe.annotation;
} else if (expression instanceof MFDataModel.LiteralExpression) {
MFDataModel.LiteralExpression le = (LiteralExpression) expression;
annotation = le.annotation;
fallbackString = "{|" + le.arg.value + "|}";
toFormat = resolveLiteralOrVariable(le.arg, variables, arguments);
} else if (expression instanceof MFDataModel.Markup) {
// No output on markup, for now (we only format to string)
return new FormattedPlaceholder(expression, new PlainStringFormattedValue(""));
} else {
if (expression == null) {
fatalFormattingError("unexpected null expression");
} else {
fatalFormattingError("unknown expression type "
+ expression.getClass().getName());
}
}
if (annotation instanceof FunctionAnnotation) {
FunctionAnnotation fa = (FunctionAnnotation) annotation;
if (functionName != null && !functionName.equals(fa.name)) {
fatalFormattingError(
"invalid function overrides, '" + functionName + "' <> '" + fa.name + "'");
}
functionName = fa.name;
Map newOptions = convertOptions(fa.options, variables, arguments);
options.putAll(newOptions);
}
FormatterFactory funcFactory = getFormattingFunctionFactoryByName(toFormat, functionName);
if (funcFactory == null) {
if (errorHandlingBehavior == ErrorHandlingBehavior.STRICT) {
fatalFormattingError("unable to find function at " + fallbackString);
}
return new FormattedPlaceholder(expression, new PlainStringFormattedValue(fallbackString));
}
Formatter ff = funcFactory.createFormatter(locale, options);
String res = ff.formatToString(toFormat, arguments);
if (res == null) {
if (errorHandlingBehavior == ErrorHandlingBehavior.STRICT) {
fatalFormattingError("unable to format string at " + fallbackString);
}
res = fallbackString;
}
ResolvedExpression resExpression = new ResolvedExpression(toFormat, functionName, options);
return new FormattedPlaceholder(resExpression, new PlainStringFormattedValue(res));
}
static class ResolvedExpression implements Expression {
final Object argument;
final String functionName;
final Map options;
public ResolvedExpression(
Object argument, String functionName, Map options) {
this.argument = argument;
this.functionName = functionName;
this.options = options;
}
}
private Map resolveDeclarations(
List declarations, Map arguments) {
Map variables = new HashMap<>();
String name;
Expression value;
if (declarations != null) {
for (Declaration declaration : declarations) {
if (declaration instanceof InputDeclaration) {
name = ((InputDeclaration) declaration).name;
value = ((InputDeclaration) declaration).value;
} else if (declaration instanceof LocalDeclaration) {
name = ((LocalDeclaration) declaration).name;
value = ((LocalDeclaration) declaration).value;
} else {
continue;
}
try {
// There it no need to succeed in solving everything.
// For example there is no problem is `$b` is not defined below:
// .local $a = {$b :number}
// {{ Hello {$user}! }}
FormattedPlaceholder fmt = formatExpression(value, variables, arguments);
// If it works, all good
variables.put(name, fmt);
} catch (Exception e) {
// It's OK to ignore the failure in this context, see comment above.
}
}
}
return variables;
}
private static class IntVarTuple {
int integer;
final Variant variant;
public IntVarTuple(int integer, Variant variant) {
this.integer = integer;
this.variant = variant;
}
}
}