Added Change utility class for representing change events + Moved Match class to org.onlab.util
Change-Id: I08e8cd8dd92983bd2764e83016b1abc0bf29388f
diff --git a/utils/misc/src/main/java/org/onlab/util/Match.java b/utils/misc/src/main/java/org/onlab/util/Match.java
new file mode 100644
index 0000000..295e558
--- /dev/null
+++ b/utils/misc/src/main/java/org/onlab/util/Match.java
@@ -0,0 +1,157 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onlab.util;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+import java.util.Arrays;
+import java.util.Objects;
+import java.util.function.Function;
+
+/**
+ * Utility class for checking matching values.
+ *
+ * @param <T> type of value
+ */
+public final class Match<T> {
+
+ public static final Match ANY = new Match<>();
+ public static final Match NULL = new Match<>(null, false);
+ public static final Match NOT_NULL = new Match<>(null, true);
+
+ private final boolean matchAny;
+ private final T value;
+ private final boolean negation;
+
+ /**
+ * Returns a Match that matches any value including null.
+ * @param <T> match type
+ * @return new instance
+ */
+ public static <T> Match<T> any() {
+ return ANY;
+ }
+
+ /**
+ * Returns a Match that matches null values.
+ * @param <T> match type
+ * @return new instance
+ */
+ public static <T> Match<T> ifNull() {
+ return NULL;
+ }
+
+ /**
+ * Returns a Match that matches all non-null values.
+ * @param <T> match type
+ * @return new instance
+ */
+ public static <T> Match<T> ifNotNull() {
+ return NOT_NULL;
+ }
+
+ /**
+ * Returns a Match that only matches the specified value.
+ * @param value value to match
+ * @param <T> match type
+ * @return new instance
+ */
+ public static <T> Match<T> ifValue(T value) {
+ return new Match<>(value, false);
+ }
+
+ /**
+ * Returns a Match that matches any value except the specified value.
+ * @param value value to not match
+ * @param <T> match type
+ * @return new instance
+ */
+ public static <T> Match<T> ifNotValue(T value) {
+ return new Match<>(value, true);
+ }
+
+ private Match() {
+ matchAny = true;
+ negation = false;
+ value = null;
+ }
+
+ private Match(T value, boolean negation) {
+ matchAny = false;
+ this.value = value;
+ this.negation = negation;
+ }
+
+ /**
+ * Maps this instance to a Match of another type.
+ * @param mapper transformation function
+ * @param <V> new match type
+ * @return new instance
+ */
+ public <V> Match<V> map(Function<T, V> mapper) {
+ if (matchAny) {
+ return any();
+ } else if (value == null) {
+ return negation ? ifNotNull() : ifNull();
+ } else {
+ return negation ? ifNotValue(mapper.apply(value)) : ifValue(mapper.apply(value));
+ }
+ }
+
+ /**
+ * Checks if this instance matches specified value.
+ * @param other other value
+ * @return true if matches; false otherwise
+ */
+ public boolean matches(T other) {
+ if (matchAny) {
+ return true;
+ } else if (other == null) {
+ return negation ? value != null : value == null;
+ } else {
+ if (value instanceof byte[]) {
+ boolean equal = Arrays.equals((byte[]) value, (byte[]) other);
+ return negation ? !equal : equal;
+ }
+ return negation ? !Objects.equals(value, other) : Objects.equals(value, other);
+ }
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(matchAny, value, negation);
+ }
+
+ @Override
+ public boolean equals(Object other) {
+ if (!(other instanceof Match)) {
+ return false;
+ }
+ Match<T> that = (Match<T>) other;
+ return Objects.equals(this.matchAny, that.matchAny) &&
+ Objects.equals(this.value, that.value) &&
+ Objects.equals(this.negation, that.negation);
+ }
+
+ @Override
+ public String toString() {
+ return toStringHelper(this)
+ .add("matchAny", matchAny)
+ .add("negation", negation)
+ .add("value", value)
+ .toString();
+ }
+}
diff --git a/utils/misc/src/main/java/org/onlab/util/Tools.java b/utils/misc/src/main/java/org/onlab/util/Tools.java
index ffefbfd..296e14b 100644
--- a/utils/misc/src/main/java/org/onlab/util/Tools.java
+++ b/utils/misc/src/main/java/org/onlab/util/Tools.java
@@ -54,6 +54,7 @@
import org.slf4j.Logger;
+import com.google.common.base.Charsets;
import com.google.common.base.Strings;
import com.google.common.primitives.UnsignedLongs;
import com.google.common.util.concurrent.ThreadFactoryBuilder;
@@ -210,6 +211,20 @@
}
/**
+ * Returns the UTF-8 encoded byte[] representation of a String.
+ */
+ public static byte[] getBytesUtf8(String input) {
+ return input.getBytes(Charsets.UTF_8);
+ }
+
+ /**
+ * Returns the String representation of UTF-8 encoded byte[].
+ */
+ public static String toStringUtf8(byte[] input) {
+ return new String(input, Charsets.UTF_8);
+ }
+
+ /**
* Returns a copy of the input byte array.
*
* @param original input
diff --git a/utils/misc/src/test/java/org/onlab/util/MatchTest.java b/utils/misc/src/test/java/org/onlab/util/MatchTest.java
new file mode 100644
index 0000000..d0b1b78
--- /dev/null
+++ b/utils/misc/src/test/java/org/onlab/util/MatchTest.java
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onlab.util;
+
+import static junit.framework.TestCase.assertEquals;
+import static junit.framework.TestCase.assertFalse;
+import static junit.framework.TestCase.assertTrue;
+
+import org.junit.Test;
+
+import com.google.common.base.Objects;
+
+/**
+ * Unit tests for Match.
+ */
+public class MatchTest {
+
+ @Test
+ public void testMatches() {
+ Match<String> m1 = Match.any();
+ assertTrue(m1.matches(null));
+ assertTrue(m1.matches("foo"));
+ assertTrue(m1.matches("bar"));
+
+ Match<String> m2 = Match.ifNull();
+ assertTrue(m2.matches(null));
+ assertFalse(m2.matches("foo"));
+
+ Match<String> m3 = Match.ifValue("foo");
+ assertFalse(m3.matches(null));
+ assertFalse(m3.matches("bar"));
+ assertTrue(m3.matches("foo"));
+ }
+
+ @Test
+ public void testEquals() {
+ Match<String> m1 = Match.any();
+ Match<String> m2 = Match.any();
+ Match<String> m3 = Match.ifNull();
+ Match<String> m4 = Match.ifValue("bar");
+ assertEquals(m1, m2);
+ assertFalse(Objects.equal(m1, m3));
+ assertFalse(Objects.equal(m3, m4));
+ }
+
+ @Test
+ public void testMap() {
+ Match<String> m1 = Match.ifNull();
+ assertEquals(m1.map(s -> "bar"), Match.ifNull());
+ Match<String> m2 = Match.ifValue("foo");
+ Match<String> m3 = m2.map(s -> "bar");
+ assertTrue(m3.matches("bar"));
+ }
+}