#6286 Container filtering improvements: Not (negation) filter and unit test

svn changeset:17750/svn branch:6.6

2 files changed, 106 insertions, 0 deletions

diff --git a/src/com/vaadin/data/util/filter/Not.java b/src/com/vaadin/data/util/filter/Not.java
new file mode 100644
index 0000000000..0e2ec4c55e
--- /dev/null
+++ b/src/com/vaadin/data/util/filter/Not.java
@@ -0,0 +1,64 @@
+package com.vaadin.data.util.filter;
+
+import com.vaadin.data.Container.Filter;
+import com.vaadin.data.Item;
+
+/**
+ * Negating filter that accepts the items rejected by another filter.
+ * 
+ * This filter directly supports in-memory filtering when the negated filter
+ * does so.
+ * 
+ * @since 6.6
+ */
+public class Not implements Filter {
+    private final Filter filter;
+
+    /**
+     * Constructs a filter that negates a filter.
+     * 
+     * @param filter
+     *            {@link Filter} to negate, not-null
+     */
+    public Not(Filter filter) {
+        this.filter = filter;
+    }
+
+    /**
+     * Returns the negated filter.
+     * 
+     * @return Filter
+     */
+    public Filter getFilter() {
+        return filter;
+    }
+
+    public boolean passesFilter(Item item) throws UnsupportedOperationException {
+        return !filter.passesFilter(item);
+    }
+
+    /**
+     * Returns true if a change in the named property may affect the filtering
+     * result. Return value is the same as {@link #appliesToProperty(Object)}
+     * for the negated filter.
+     * 
+     * @return boolean
+     */
+    public boolean appliesToProperty(Object propertyId) {
+        return filter.appliesToProperty(propertyId);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null || !getClass().equals(obj.getClass())) {
+            return false;
+        }
+        return filter.equals(((Not) obj).getFilter());
+    }
+
+    @Override
+    public int hashCode() {
+        return filter.hashCode();
+    }
+
+}
diff --git a/tests/src/com/vaadin/tests/server/container/filter/NotFilterTest.java b/tests/src/com/vaadin/tests/server/container/filter/NotFilterTest.java
new file mode 100644
index 0000000000..983b4cf60a
--- /dev/null
+++ b/tests/src/com/vaadin/tests/server/container/filter/NotFilterTest.java
@@ -0,0 +1,42 @@
+package com.vaadin.tests.server.container.filter;
+
+import junit.framework.Assert;
+
+import com.vaadin.data.Container.Filter;
+import com.vaadin.data.Item;
+import com.vaadin.data.util.BeanItem;
+import com.vaadin.data.util.filter.And;
+import com.vaadin.data.util.filter.Not;
+
+public class NotFilterTest extends AbstractFilterTest {
+
+    protected Item item1 = new BeanItem<Integer>(1);
+    protected Item item2 = new BeanItem<Integer>(2);
+
+    public void testNot() {
+        Filter origFilter = new SameItemFilter(item1);
+        Filter filter = new Not(origFilter);
+
+        Assert.assertTrue(origFilter.passesFilter(item1));
+        Assert.assertFalse(origFilter.passesFilter(item2));
+        Assert.assertFalse(filter.passesFilter(item1));
+        Assert.assertTrue(filter.passesFilter(item2));
+    }
+
+    public void testNotEqualsHashCode() {
+        Filter origFilter = new SameItemFilter(item1);
+        Filter filter1 = new Not(origFilter);
+        Filter filter1b = new Not(new SameItemFilter(item1));
+        Filter filter2 = new Not(new SameItemFilter(item2));
+
+        // equals()
+        Assert.assertEquals(filter1, filter1b);
+        Assert.assertFalse(filter1.equals(filter2));
+        Assert.assertFalse(filter1.equals(origFilter));
+        Assert.assertFalse(filter1.equals(new And()));
+
+        // hashCode()
+        Assert.assertEquals(filter1.hashCode(), filter1b.hashCode());
+    }
+
+}