From bd2e8599a3a462582745723743ddb13f00b7dc99 Mon Sep 17 00:00:00 2001
From: =?utf8?q?David=20=E2=80=98Bombe=E2=80=99=20Roden?=
 <bombe@pterodactylus.net>
Date: Fri, 15 Jul 2011 11:15:57 +0200
Subject: [PATCH] Add filter that uniquifies collections.

---
 .../sone/template/UniqueElementFilter.java         | 46 ++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 src/main/java/net/pterodactylus/sone/template/UniqueElementFilter.java

diff --git a/src/main/java/net/pterodactylus/sone/template/UniqueElementFilter.java b/src/main/java/net/pterodactylus/sone/template/UniqueElementFilter.java
new file mode 100644
index 0000000..70dae70
--- /dev/null
+++ b/src/main/java/net/pterodactylus/sone/template/UniqueElementFilter.java
@@ -0,0 +1,46 @@
+/*
+ * Sone - UniqueElementFilter.java - Copyright © 2011 David Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sone.template;
+
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+import net.pterodactylus.util.template.Filter;
+import net.pterodactylus.util.template.TemplateContext;
+
+/**
+ * Filter that reduces a collection to a {@link Set}, removing duplicates.
+ *
+ * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
+ */
+public class UniqueElementFilter implements Filter {
+
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public Object format(TemplateContext templateContext, Object data, Map<String, String> parameters) {
+		if (!(data instanceof Collection<?>)) {
+			return data;
+		}
+		return new HashSet<Object>((Collection<?>) data);
+	}
+
+}
-- 
2.7.4