1 files changed, 49 insertions, 0 deletions
diff --git a/hamcrest-core/src/org/hamcrest/core/IsNot.java b/hamcrest-core/src/org/hamcrest/core/IsNot.java
new file mode 100644
index 0000000..cb6946c
--- /dev/null
+++ b/hamcrest-core/src/org/hamcrest/core/IsNot.java
@@ -0,0 +1,49 @@
+/*  Copyright (c) 2000-2006 hamcrest.org
+ */
+package org.hamcrest.core;
+
+import static org.hamcrest.core.IsEqual.equalTo;
+import org.hamcrest.Description;
+import org.hamcrest.Matcher;
+import org.hamcrest.Factory;
+import org.hamcrest.BaseMatcher;
+
+
+/**
+ * Calculates the logical negation of a matcher.
+ */
+public class IsNot<T> extends BaseMatcher<T> {
+    private final Matcher<T> matcher;
+
+    public IsNot(Matcher<T> matcher) {
+        this.matcher = matcher;
+    }
+
+    public boolean matches(Object arg) {
+        return !matcher.matches(arg);
+    }
+
+    public void describeTo(Description description) {
+        description.appendText("not ").appendDescriptionOf(matcher);
+    }
+
+    /**
+     * Inverts the rule.
+     */
+    @Factory
+    public static <T> Matcher<T> not(Matcher<T> matcher) {
+        return new IsNot<T>(matcher);
+    }
+
+    /**
+     * This is a shortcut to the frequently used not(equalTo(x)).
+     *
+     * eg. assertThat(cheese, is(not(equalTo(smelly))))
+     * vs  assertThat(cheese, is(not(smelly)))
+     */
+    @Factory
+    public static <T> Matcher<T> not(T value) {
+        return not(equalTo(value));
+    }
+
+}