use diamond operator (#628)

diamond operator is Java 7 feature. handlebars already dropped Java 6
#426

Author: xuwei-k

handlebars/src/main/java/com/github/jknack/handlebars/Context.java

@@ -218,7 +218,7 @@ public Object resolve(final Object context) {
 
     @Override
     public Set<Entry<String, Object>> propertySet(final Object context) {
-      Set<Entry<String, Object>> propertySet = new LinkedHashSet<Map.Entry<String, Object>>();
+      Set<Entry<String, Object>> propertySet = new LinkedHashSet<>();
       for (ValueResolver resolver : resolvers) {
         propertySet.addAll(resolver.propertySet(context));
       }
@@ -453,7 +453,7 @@ protected Context(final Object model) {
   private static Context root(final Object model) {
     Context root = new Context(model);
     root.extendedContext = new Context(new HashMap<String, Object>());
-    root.data = new HashMap<String, Object>();
+    root.data = new HashMap<>();
     root.data.put(PARTIALS, new HashMap<String, Template>());
     LinkedList<Map<String, Template>> partials = new LinkedList<>();
     partials.push(new HashMap<String, Template>());
@@ -738,7 +738,7 @@ public static Context newContext(final Context parent, final Object model) {
    */
   public static Context newBlockParamContext(final Context parent, final List<String> names,
       final List<Object> values) {
-    Map<String, Object> hash = new HashMap<String, Object>();
+    Map<String, Object> hash = new HashMap<>();
     for (int i = 0; i < Math.min(values.size(), names.size()); i++) {
       hash.put(names.get(i), values.get(i));
     }

handlebars/src/main/java/com/github/jknack/handlebars/Handlebars.java

@@ -310,7 +310,7 @@ public static CharSequence escapeExpression(final CharSequence input) {
   private String handlebarsJsFile = "/handlebars-v4.0.4.js";
 
   /** List of formatters. */
-  private List<Formatter> formatters = new ArrayList<Formatter>();
+  private List<Formatter> formatters = new ArrayList<>();
 
   /** Default formatter. */
   private Formatter.Chain formatter = Formatter.NOOP;

handlebars/src/main/java/com/github/jknack/handlebars/cache/HighConcurrencyTemplateCache.java

@@ -161,7 +161,7 @@ private Template cacheGet(final TemplateSource source, final Parser parser) thro
    */
   private FutureTask<Pair<TemplateSource, Template>> newTask(final TemplateSource source,
       final Parser parser) {
-    return new FutureTask<Pair<TemplateSource, Template>>(
+    return new FutureTask<>(
         new Callable<Pair<TemplateSource, Template>>() {
           @Override
           public Pair<TemplateSource, Template> call() throws IOException {

handlebars/src/main/java/com/github/jknack/handlebars/context/FieldValueResolver.java

@@ -221,7 +221,7 @@ protected Object invokeMember(final FieldWrapper field, final Object context) {
 
   @Override
   protected Set<FieldWrapper> members(final Class<?> clazz) {
-    Set<FieldWrapper> members = new LinkedHashSet<FieldWrapper>();
+    Set<FieldWrapper> members = new LinkedHashSet<>();
     if (clazz.isArray()) {
       members.add(ArrayLengthMember.LENGTH);
     } else {

handlebars/src/main/java/com/github/jknack/handlebars/context/MemberValueResolver.java

@@ -163,7 +163,7 @@ public Set<Entry<String, Object>> propertySet(final Object context) {
       return Collections.emptySet();
     }
     Collection<M> members = cache(context.getClass()).values();
-    Map<String, Object> propertySet = new LinkedHashMap<String, Object>();
+    Map<String, Object> propertySet = new LinkedHashMap<>();
     for (M member : members) {
       String name = memberName(member);
       propertySet.put(name, resolve(context, name));

handlebars/src/main/java/com/github/jknack/handlebars/context/MethodValueResolver.java

@@ -68,7 +68,7 @@ protected Object invokeMember(final Method member, final Object context) {
 
   @Override
   protected Set<Method> members(final Class<?> clazz) {
-    Set<Method> members = new LinkedHashSet<Method>();
+    Set<Method> members = new LinkedHashSet<>();
     members(clazz, members);
     return members;
   }

handlebars/src/main/java/com/github/jknack/handlebars/helper/BlockHelper.java

@@ -81,7 +81,7 @@ public Object apply(final Object context, final Options options)
       template = options.fn;
     }
     // Get hash from current block and merge partial hash (if any).
-    Map<String, Object> hash = new LinkedHashMap<String, Object>(options.hash);
+    Map<String, Object> hash = new LinkedHashMap<>(options.hash);
     Map<String, Object> partialHash = options.data(Context.PARTIALS + "#" + context + "#hash");
     if (partialHash != null) {
       hash.putAll(partialHash);

handlebars/src/main/java/com/github/jknack/handlebars/helper/DefaultHelperRegistry.java

@@ -59,7 +59,7 @@ public class DefaultHelperRegistry implements HelperRegistry {
   /**
    * The helper registry.
    */
-  private final Map<String, Helper<?>> helpers = new HashMap<String, Helper<?>>();
+  private final Map<String, Helper<?>> helpers = new HashMap<>();
 
   /** Decorators. */
   private final Map<String, Decorator> decorators = new HashMap<>();
@@ -191,7 +191,7 @@ public Set<Entry<String, Helper<?>>> helpers() {
    */
   private void registerDynamicHelper(final Object source, final Class<?> clazz) {
     if (clazz != Object.class) {
-      Set<String> overloaded = new HashSet<String>();
+      Set<String> overloaded = new HashSet<>();
       // Keep backing up the inheritance hierarchy.
       Method[] methods = clazz.getDeclaredMethods();
       for (Method method : methods) {

handlebars/src/main/java/com/github/jknack/handlebars/helper/I18nHelper.java

@@ -410,7 +410,7 @@ public DefI18nSource(final Charset charset, final String baseName, final Locale
   @Override
   public String[] keys(final String basename, final Locale locale) {
     Enumeration<String> keys = bundle.getKeys();
-    List<String> result = new ArrayList<String>();
+    List<String> result = new ArrayList<>();
     while (keys.hasMoreElements()) {
       String key = keys.nextElement();
       result.add(key);

handlebars/src/main/java/com/github/jknack/handlebars/internal/BaseTemplate.java

@@ -342,11 +342,11 @@ public Object invoke(final Object proxy, final Method method, final Object[] met
   @Override
   public List<String> collect(final TagType... tagType) {
     isTrue(tagType.length > 0, "At least one tag type is required.");
-    Set<String> tagNames = new LinkedHashSet<String>();
+    Set<String> tagNames = new LinkedHashSet<>();
     for (TagType tt : tagType) {
       collect(tagNames, tt);
     }
-    return new ArrayList<String>(tagNames);
+    return new ArrayList<>(tagNames);
   }
 
   /**
@@ -361,9 +361,9 @@ protected void collect(final Collection<String> result, final TagType tagType) {
 
   @Override
   public List<String> collectReferenceParameters() {
-    Set<String> paramNames = new LinkedHashSet<String>();
+    Set<String> paramNames = new LinkedHashSet<>();
     collectReferenceParameters(paramNames);
-    return new ArrayList<String>(paramNames);
+    return new ArrayList<>(paramNames);
   }
 
   /**