JSF2.0 multi-language composite component - jsf-2

Question

To internationalize a composite component, you have to put a .properties file that has the exact same name than the component itself and in the same folder.
From the xhtml, you can access these translations through ${cc.resourceBundleMap.key}.
Until now, all is fine and works for me. Where the problems starts is when I add more .properties files for other languages. No matter which local is my computer in, the picked language is the default one (component.properties).
This seems to be a recurrent problem since Ziletka also reports the same problem in How to localize JSF 2 composite components, but remained unanswered.
I have tried all sort of possibilities:
no default .properties file
component_fr.properties
component_fr_CA.properties
component_fr_FR.properties
component_en.properties
component_en_CA.properties
component_en_US.properties
but it results in a:
javax.el.ELException: [...] /resources/component/component.xhtml default="${cc.resourceBundleMap.key}": java.lang.NullPointerException
with default .properties file plus Language specification
component.properties
component_fr.properties
component_en.properties
only the default is loaded.
with default .properties file plus Language and Country specifications
component.properties
component_fr_CA.properties
component_fr_FR.properties
component_en_CA.properties
component_en_US.properties
And again: only the default is loaded.
I would love to avoid having to rely on the backing bean to provide the translations and can't resolve into believing that it is not supported. Can anyone help?

Answer 1

This feature was implemented long time ago in MyFaces Core. See: MYFACES-3308. The test case done can be found here
The locale applied to the composite component depends on the value retrieved from UIViewRoot.getLocale().

Answer 2

Apparently the problem is still there and its root is in the javax.faces.component.UIComponent class particularly in the findComponentResourceBundleLocaleMatch method. The snipped is below
private Resource findComponentResourceBundleLocaleMatch(FacesContext context,
String resourceName, String libraryName) {
Resource result = null;
ResourceBundle resourceBundle = null;
int i;
if (-1 != (i = resourceName.lastIndexOf("."))) {
resourceName = resourceName.substring(0, i) +
".properties"; //THE PROBLEM IS HERE
if (null != context) {
result = context.getApplication().getResourceHandler().
createResource(resourceName, libraryName);
InputStream propertiesInputStream = null;
try {
propertiesInputStream = result.getInputStream();
resourceBundle = new PropertyResourceBundle(propertiesInputStream);
} catch (IOException ex) {
Logger.getLogger(UIComponent.class.getName()).log(Level.SEVERE, null, ex);
} finally{
if(null != propertiesInputStream){
try{
propertiesInputStream.close();
} catch(IOException ioe){
if (LOGGER.isLoggable(Level.SEVERE)) {
LOGGER.log(Level.SEVERE, null, ioe);
}
}
}
}
}
}
result = (null != resourceBundle) ? result : null;
return result;
}
You can see it at the line with a comment that states 'THE PROBLEM IS HERE'. Precisely when it looks for a properties file to load it does not respect any language and/or country code. It always loads a default resource.
Possible solution
The 'problematic' method is called from another method getResourceBundleMap of the same class and a part of the code you are interested in is marked with a comment (line #1000)
// Step 2: if this is a composite component, look for a
// ResourceBundle as a Resource
Which is no surprise as you need a composite component. So the solution would be to define a backing component class for your composite component and redefine resourceBundleMap loading. Below you may find the implementation that respects language only which means it would work for files like componentName_en.properties and componentName_de.properties but would not for something like componentName_en_US.properties
Your .properties files should be in the same directory as the definition of your component
testComponent.properties
testComponent_de.properties
testComponent_en.properties
testComponent_fr.properties
in your component testComponent.xhtmlspecify a definition class in componentType attribute.
<cc:interface componentType="test.component">
....
</cc:interface>
The component may look as following. I used the original code mostly with couple changes. The idea is to override the problematic method and withing the code try reading a properties file for a specified language first and if it is not found, read the default one.
#FacesComponent("test.component")
public class TestComponent extends UINamingContainer {
private static final String PROPERTIES_EXT = ".properties";
private Logger LOGGER = <use one you like>;
private Map<String, String> resourceBundleMap = null;
#Override
public Map<String, String> getResourceBundleMap() {
ResourceBundle resourceBundle = null;
if (null == resourceBundleMap) {
FacesContext context = FacesContext.getCurrentInstance();
UIViewRoot root = context.getViewRoot();
Locale currentLocale = null;
if (null != context) {
if (null != root) {
currentLocale = root.getLocale();
}
}
if (null == currentLocale) {
currentLocale = Locale.getDefault();
}
if (this.getAttributes().containsKey(Resource.COMPONENT_RESOURCE_KEY)) {
Resource ccResource = (Resource)
this.getAttributes().get(Resource.COMPONENT_RESOURCE_KEY);
if (null != ccResource) {
InputStream propertiesInputStream = null;
try {
propertiesInputStream = ccResource.getInputStream();
resourceBundle = findComponentResourceBundleLocaleMatch(ccResource.getResourceName(),
ccResource.getLibraryName(), currentLocale.getLanguage());
} catch (IOException ex) {
LOGGER.error(null, ex);
} finally {
if (null != propertiesInputStream) {
try {
propertiesInputStream.close();
} catch (IOException ioe) {
LOGGER.error(null, ioe);
}
}
}
}
}
if (null != resourceBundle) {
final ResourceBundle bundle = resourceBundle;
resourceBundleMap =
new Map() {
// this is an immutable Map
public String toString() {
StringBuffer sb = new StringBuffer();
Iterator<Map.Entry<String, Object>> entries =
this.entrySet().iterator();
Map.Entry<String, Object> cur;
while (entries.hasNext()) {
cur = entries.next();
sb.append(cur.getKey()).append(": ").append(cur.getValue()).append('\n');
}
return sb.toString();
}
// Do not need to implement for immutable Map
public void clear() {
throw new UnsupportedOperationException();
}
public boolean containsKey(Object key) {
boolean result = false;
if (null != key) {
result = (null != bundle.getObject(key.toString()));
}
return result;
}
public boolean containsValue(Object value) {
Enumeration<String> keys = bundle.getKeys();
boolean result = false;
while (keys.hasMoreElements()) {
Object curObj = bundle.getObject(keys.nextElement());
if ((curObj == value) ||
((null != curObj) && curObj.equals(value))) {
result = true;
break;
}
}
return result;
}
public Set<Map.Entry<String, Object>> entrySet() {
HashMap<String, Object> mappings = new HashMap<String, Object>();
Enumeration<String> keys = bundle.getKeys();
while (keys.hasMoreElements()) {
String key = keys.nextElement();
Object value = bundle.getObject(key);
mappings.put(key, value);
}
return mappings.entrySet();
}
#Override
public boolean equals(Object obj) {
return !((obj == null) || !(obj instanceof Map))
&& entrySet().equals(((Map) obj).entrySet());
}
public Object get(Object key) {
if (null == key) {
return null;
}
try {
return bundle.getObject(key.toString());
} catch (MissingResourceException e) {
return "???" + key + "???";
}
}
public int hashCode() {
return bundle.hashCode();
}
public boolean isEmpty() {
Enumeration<String> keys = bundle.getKeys();
return !keys.hasMoreElements();
}
public Set keySet() {
Set<String> keySet = new HashSet<String>();
Enumeration<String> keys = bundle.getKeys();
while (keys.hasMoreElements()) {
keySet.add(keys.nextElement());
}
return keySet;
}
// Do not need to implement for immutable Map
public Object put(Object k, Object v) {
throw new UnsupportedOperationException();
}
// Do not need to implement for immutable Map
public void putAll(Map t) {
throw new UnsupportedOperationException();
}
// Do not need to implement for immutable Map
public Object remove(Object k) {
throw new UnsupportedOperationException();
}
public int size() {
int result = 0;
Enumeration<String> keys = bundle.getKeys();
while (keys.hasMoreElements()) {
keys.nextElement();
result++;
}
return result;
}
public java.util.Collection values() {
ArrayList<Object> result = new ArrayList<Object>();
Enumeration<String> keys = bundle.getKeys();
while (keys.hasMoreElements()) {
result.add(
bundle.getObject(keys.nextElement()));
}
return result;
}
};
}
if (null == resourceBundleMap) {
resourceBundleMap = Collections.EMPTY_MAP;
}
}
return resourceBundleMap;
}
private ResourceBundle findComponentResourceBundleLocaleMatch(String resourceName, String libraryName, String lng) {
FacesContext context = FacesContext.getCurrentInstance();
ResourceBundle resourceBundle = null;
int i;
if (-1 != (i = resourceName.lastIndexOf("."))) {
if (null != context) {
InputStream propertiesInputStream = null;
try {
propertiesInputStream = getResourceInputStream(context, resourceName.substring(0, i), libraryName, lng);
resourceBundle = new PropertyResourceBundle(propertiesInputStream);
} catch (IOException ex) {
LOGGER.error(null, ex);
} finally {
if (null != propertiesInputStream) {
try {
propertiesInputStream.close();
} catch (IOException ioe) {
LOGGER.error(null, ioe);
}
}
}
}
}
return resourceBundle;
}
private InputStream getResourceInputStream(FacesContext context, final String resourceName, String libraryName, String lng) throws IOException {
InputStream propertiesInputStream = null;
propertiesInputStream = getPropertiesResourceInputStream(context, String.format("%s_%s%s", resourceName, lng, PROPERTIES_EXT), libraryName);
if (null == propertiesInputStream) {
propertiesInputStream = getPropertiesResourceInputStream(context, resourceName + PROPERTIES_EXT, libraryName);
}
return propertiesInputStream;
}
private InputStream getPropertiesResourceInputStream(FacesContext context, final String resourceName, String libraryName) throws IOException {
Resource result = context.getApplication().getResourceHandler().createResource(resourceName, libraryName);
if (null == result) {
return null;
}
return result.getInputStream();
}
}
Done.
However that is obviously a bug in the Mojarra and I hope it will be fixed soon. Closer look to the code related to the composite components reveals that the default .properties file for a component is read twice which I guess is not a very good idea too, but this is another story.
PS. You may easily adjust te code to respect country code as well if you wish.