Using diamond operator

src/main/java/io/airlift/airline/Accessor.java

@@ -146,10 +146,10 @@ public String toString()
     private static Collection<Object> newCollection(Class<?> type)
     {
         if (Collection.class.equals(type) || List.class.equals(type)) {
-            return new ArrayList<Object>();
+            return new ArrayList<>();
         }
         if (Set.class.equals(type)) {
-            return new HashSet<Object>();
+            return new HashSet<>();
         }
         if (SortedSet.class.equals(type)) {
             return new TreeSet();

src/main/java/io/airlift/airline/Cli.java

@@ -43,7 +43,7 @@ public class Cli<C>
     public static <T> CliBuilder<T> builder(String name)
     {
         Preconditions.checkNotNull(name, "name is null");
-        return new CliBuilder<T>(name);
+        return new CliBuilder<>(name);
     }
 
     @Deprecated
@@ -281,14 +281,14 @@ public GroupBuilder<C> withGroup(String name)
                 return groups.get(name);
             }
 
-            GroupBuilder<C> group = new GroupBuilder<C>(name);
+            GroupBuilder<C> group = new GroupBuilder<>(name);
             groups.put(name, group);
             return group;
         }
 
         public Cli<C> build()
         {
-            return new Cli<C>(name, description, typeConverter, defaultCommand, defaultCommandGroupCommands, groups.values());
+            return new Cli<>(name, description, typeConverter, defaultCommand, defaultCommandGroupCommands, groups.values());
         }
     }
 

src/main/java/io/airlift/airline/CommandUsage.java

@@ -147,7 +147,7 @@ public void usage(@Nullable String programName, @Nullable String groupName, Stri
     private List<OptionMetadata> sortOptions(List<OptionMetadata> options)
     {
         if (optionComparator != null) {
-            options = new ArrayList<OptionMetadata>(options);
+            options = new ArrayList<>(options);
             Collections.sort(options, optionComparator);
         }
         return options;

src/main/java/io/airlift/airline/SingleCommand.java

@@ -34,7 +34,7 @@ public class SingleCommand<C>
 {
     public static <C> SingleCommand<C> singleCommand(Class<C> command)
     {
-        return new SingleCommand<C>(command);
+        return new SingleCommand<>(command);
     }
 
     private final CommandMetadata commandMetadata;