package com.googlecode.gwt.test.internal.i18n;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.text.MessageFormat;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import com.google.gwt.i18n.client.LocalizableResource;
import com.google.gwt.i18n.client.Messages.AlternateMessage;
import com.google.gwt.i18n.client.Messages.DefaultMessage;
import com.google.gwt.i18n.client.Messages.PluralCount;
import com.google.gwt.i18n.client.Messages.PluralText;
import com.google.gwt.i18n.client.Messages.Select;
import com.google.gwt.i18n.client.PluralRule;
import com.google.gwt.i18n.client.impl.plurals.DefaultRule;
import com.google.gwt.safehtml.shared.SafeHtml;
import com.google.gwt.safehtml.shared.SafeHtmlUtils;
import com.googlecode.gwt.test.exceptions.GwtTestI18NException;
import com.googlecode.gwt.test.utils.GwtReflectionUtils;
@SuppressWarnings("deprecation")
class MessagesInvocationHandler extends LocalizableResourceInvocationHandler {
public MessagesInvocationHandler(Class<? extends LocalizableResource> proxiedClass) {
super(proxiedClass);
}
@Override
protected Object extractDefaultValue(Method method, Object[] args) throws Throwable {
DefaultMessage defaultMessage = method.getAnnotation(DefaultMessage.class);
Annotation messageAnnotation = getMessageAnnotation(method);
String valuePattern = null;
if (messageAnnotation != null) {
String key = extractPluralCountAndSelectValues(messageAnnotation, method, args,
getLocale());
String[] values = getMessageAnnotationValues(messageAnnotation);
valuePattern = getAnnotationValues(values).get(key);
}
if (valuePattern == null && defaultMessage != null) {
valuePattern = defaultMessage.value();
}
if (valuePattern != null) {
String result = format(valuePattern, args, getLocale());
// handle SafeHtml return type
return method.getReturnType() == SafeHtml.class ? SafeHtmlUtils.fromTrustedString(result)
: result;
}
return null;
}
@Override
protected Object extractFromProperties(Properties localizedProperties, Method method,
Object[] args, Locale locale) throws Throwable {
Annotation messageAnnotation = getMessageAnnotation(method);
String key = messageAnnotation == null ? getKey(method) : getSpecificKey(messageAnnotation,
method, args, locale);
String result = extractProperty(localizedProperties, key);
if (result != null) {
result = format(result, args, locale);
// handle SafeHtml return type
return method.getReturnType() == SafeHtml.class ? SafeHtmlUtils.fromTrustedString(result)
: result;
}
return null;
}
protected String extractProperty(Properties properties, String key) {
String result = properties.getProperty(key);
if (result == null) {
result = properties.getProperty(key.replaceAll("_", "."));
}
return result;
}
/**
* Get the {@link PluralCount} and/or {@link Select} value which correspond to the method call.
* if there are many @PluralCount and/or @Select annotated args, the corresponding values are
* appended with the '|' separator.
*
* @param messageAnnotation The annotation which has been detected. Can be a
* {@link AlternateMessage} or a {@link PluralText}
* @param method The i18n called method
* @param args The parameter passed to the i18n method during the call
* @param locale The locale to use
* @return A String in which are appended all the {@link PluralCount} and {@link Select} value,
* or null if there is no such annotations
*/
@SuppressWarnings("unchecked")
private String extractPluralCountAndSelectValues(Annotation messageAnnotation, Method method,
Object[] args, Locale locale) {
Annotation[][] annotations = method.getParameterAnnotations();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < annotations.length; i++) {
Annotation[] childArray = annotations[i];
for (int j = 0; j < childArray.length; j++) {
if (PluralCount.class.isAssignableFrom(childArray[j].getClass())) {
PluralCount pluralCount = (PluralCount) childArray[j];
Class<? extends PluralRule> pluralRuleClass = pluralCount.value();
int count = (Integer) args[i];
String pluralRuleClassName = pluralRuleClass != PluralRule.class
? pluralRuleClass.getName() : DefaultRule.class.getName();
pluralRuleClassName += "_" + locale.getLanguage();
try {
Class<? extends PluralRule> acutalRule = (Class<? extends PluralRule>) GwtReflectionUtils.getClass(pluralRuleClassName);
PluralRule ruleInstance = acutalRule.newInstance();
sb.append(ruleInstance.pluralForms()[ruleInstance.select(count)].getName()).append(
"|");
} catch (ClassNotFoundException e) {
throw new GwtTestI18NException("Cannot find PluralRule for method '"
+ method.getDeclaringClass().getSimpleName() + "." + method.getName()
+ "()'. Expected PluralRule : '" + pluralRuleClassName + "'");
} catch (InstantiationException e) {
throw new GwtTestI18NException("Error during instanciation of class '"
+ pluralRuleClassName + "'", e);
} catch (IllegalAccessException e) {
throw new GwtTestI18NException("Error during instanciation of class '"
+ pluralRuleClassName + "'", e);
}
} else if (Select.class.isAssignableFrom(childArray[j].getClass())) {
sb.append(args[i]).append("|");
}
}
}
if (sb.length() == 0) {
throw new GwtTestI18NException("Bad configuration of '" + method.getDeclaringClass() + "."
+ method.getName() + "' : a @" + messageAnnotation.getClass().getSimpleName()
+ " is declared but no @" + PluralCount.class.getSimpleName() + " or @"
+ Select.class.getSimpleName() + " set on any method parameter'");
} else {
return sb.substring(0, sb.length() - 1);
}
}
private String format(String pattern, Object[] args, Locale locale) {
MessageFormat format = locale == null ? new MessageFormat(pattern) : new MessageFormat(
pattern, locale);
return format.format(args);
}
/**
* Convert the {@link AlternateMessage#value()} or {@link PluralText#value()} string array to a
* map of possible values
*
* @param annotationValues the array value returned by {@link AlternateMessage#value()} or
* {@link PluralText#value()}
* @return a map of named values
*/
private Map<String, String> getAnnotationValues(String[] annotationValues) {
Map<String, String> pluralForms = new HashMap<String, String>();
for (int i = 0; i < annotationValues.length; i++) {
pluralForms.put(annotationValues[i], annotationValues[++i]);
}
return pluralForms;
}
/**
* Return an instance of {@link AlternateMessage} or {@link PluralText} if the i18n method is
* annotated, null otherwise.
*
* @param method The current processed i18n method
* @return an instance of {@link AlternateMessage} or {@link PluralText} if the i18n method is
* annotated, null otherwise.
*/
private Annotation getMessageAnnotation(Method method) {
Annotation specificMessageAnnotation = method.getAnnotation(AlternateMessage.class);
if (specificMessageAnnotation == null) {
specificMessageAnnotation = method.getAnnotation(PluralText.class);
}
return specificMessageAnnotation;
}
private String[] getMessageAnnotationValues(Annotation messageAnnotation) {
if (AlternateMessage.class.isInstance(messageAnnotation)) {
return ((AlternateMessage) messageAnnotation).value();
} else if (PluralText.class.isInstance(messageAnnotation)) {
return ((PluralText) messageAnnotation).value();
}
return null;
}
private String getSpecificKey(Annotation specificMessageAnnotation, Method method,
Object[] args, Locale locale) {
String pluralCountValue = extractPluralCountAndSelectValues(specificMessageAnnotation,
method, args, locale);
return method.getName() + "[" + pluralCountValue + "]";
}
}