package com.googlecode.gwt.test.internal.handlers;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.HashMap;
import java.util.Map;
import com.google.gwt.place.impl.AbstractPlaceHistoryMapper;
import com.google.gwt.place.shared.Place;
import com.google.gwt.place.shared.PlaceHistoryMapper;
import com.google.gwt.place.shared.PlaceTokenizer;
import com.google.gwt.place.shared.WithTokenizers;
import com.googlecode.gwt.test.GwtCreateHandler;
import com.googlecode.gwt.test.exceptions.GwtTestPatchException;
import com.googlecode.gwt.test.utils.GwtReflectionUtils;
class PlaceHistoryMapperCreateHandler implements GwtCreateHandler {
private static final class GwtTestPlaceHistoryMapper extends AbstractPlaceHistoryMapper<Object> {
private final Map<Class<?>, String> prefixMap;
private final Map<String, PlaceTokenizer<?>> tokenizerMap;
private GwtTestPlaceHistoryMapper(Class<? extends PlaceTokenizer<?>>[] placeTokenizers) {
this.prefixMap = new HashMap<Class<?>, String>();
this.tokenizerMap = new HashMap<String, PlaceTokenizer<?>>();
collectTokenizerByPrefix(placeTokenizers);
}
@Override
protected PrefixAndToken getPrefixAndToken(Place newPlace) {
String prefix = prefixMap.get(newPlace.getClass());
PlaceTokenizer<?> tokenizer = getTokenizer(prefix);
if (tokenizer == null) {
return null;
}
String token = GwtReflectionUtils.callPrivateMethod(tokenizer, "getToken", newPlace);
return new PrefixAndToken(prefix, token);
}
@Override
protected PlaceTokenizer<?> getTokenizer(String prefix) {
return tokenizerMap.get(prefix);
}
private void collectTokenizerByPrefix(Class<? extends PlaceTokenizer<?>>[] placeTokenizers) {
for (Class<? extends PlaceTokenizer<?>> tokenizerClass : placeTokenizers) {
try {
Method getPlaceMethod = tokenizerClass.getMethod("getPlace", String.class);
Class<?> placeClass = getPlaceMethod.getReturnType();
String placePrefix = createUniquePrefix(placeClass);
PlaceTokenizer<?> instance = GwtReflectionUtils.instantiateClass(tokenizerClass);
tokenizerMap.put(placePrefix, instance);
prefixMap.put(placeClass, placePrefix);
} catch (Exception e) {
// should never happened : just mute this throw
e.printStackTrace();
}
}
}
private String createUniquePrefix(Class<?> placeClass) {
String prefix = placeClass.getSimpleName();
String uniquePrefix = prefix;
int i = 1;
while (tokenizerMap.containsKey(uniquePrefix)) {
uniquePrefix = prefix + i;
i++;
}
return uniquePrefix;
}
}
private static final class PlaceHistoryInvocationHandler implements InvocationHandler {
private final GwtTestPlaceHistoryMapper placeHistoryMapper;
private PlaceHistoryInvocationHandler(Class<? extends PlaceTokenizer<?>>[] placeTokenizers) {
placeHistoryMapper = new GwtTestPlaceHistoryMapper(placeTokenizers);
}
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
if (method.getName().equals("getPlace")) {
return placeHistoryMapper.getPlace((String) args[0]);
} else if (method.getName().equals("getToken")) {
return placeHistoryMapper.getToken((Place) args[0]);
} else {
throw new GwtTestPatchException(
"Unhandled method '"
+ method.getDeclaringClass().getName()
+ "."
+ method.getName()
+ "' by the default gwt-test-utils GwtCreateHandler for PlaceHistoryMapper subtypes");
}
}
}
public Object create(Class<?> classLiteral) throws Exception {
if (!PlaceHistoryMapper.class.isAssignableFrom(classLiteral)) {
return null;
}
WithTokenizers withTokenizers = classLiteral.getAnnotation(WithTokenizers.class);
if (withTokenizers == null) {
throw new GwtTestPatchException(
"Error while trying to create an instance of "
+ classLiteral.getName()
+ " : gwt-test-utils default GwtCreateHandler for PlaceHistoryMapper is not currently able to create a valid implementation without relying on the @WithTokenizer annotation");
}
return Proxy.newProxyInstance(classLiteral.getClassLoader(), new Class<?>[]{classLiteral},
new PlaceHistoryInvocationHandler(withTokenizers.value()));
}
}