Initial sketch and implementaion of Objectives.

These objective will be used to provide a layer of abstraction
that isolates applications for device pipeline details.

initial objective support

Change-Id: I019302822421f0fe1f508f2f7527d91578e30116

initial implemetation of a simple pipeline behaviour

Change-Id: Id0d9167896c717d05cda90e1524fc24c76e9fc9b

initial implementation of objectives

Change-Id: I768fa2020308d5feb95eaaff355aa511b323beca
diff --git a/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultFilteringObjective.java b/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultFilteringObjective.java
new file mode 100644
index 0000000..4c1b71f
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultFilteringObjective.java
@@ -0,0 +1,186 @@
+/*
+ * 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.onosproject.net.flowobjective;
+
+import com.google.common.collect.ImmutableList;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.net.flow.criteria.Criterion;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Objects;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Default implementation of a filtering objective.
+ */
+public final class DefaultFilteringObjective implements FilteringObjective {
+
+
+    private final Criterion key;
+    private final boolean permanent;
+    private final int timeout;
+    private final ApplicationId appId;
+    private final int priority;
+    private final List<Criterion> conditions;
+    private final int id;
+    private final Operation op;
+
+    private DefaultFilteringObjective(Criterion key, boolean permanent, int timeout,
+                                      ApplicationId appId, int priority,
+                                      List<Criterion> conditions, Operation op) {
+        this.key = key;
+        this.permanent = permanent;
+        this.timeout = timeout;
+        this.appId = appId;
+        this.priority = priority;
+        this.conditions = conditions;
+        this.op = op;
+
+        this.id = Objects.hash(key, conditions, permanent,
+                               timeout, appId, priority);
+    }
+
+
+    @Override
+    public Criterion key() {
+        return key;
+    }
+
+    @Override
+    public Collection<Criterion> conditions() {
+        return conditions;
+    }
+
+    @Override
+    public int id() {
+        return id;
+    }
+
+    @Override
+    public int priority() {
+        return priority;
+    }
+
+    @Override
+    public ApplicationId appId() {
+        return appId;
+    }
+
+    @Override
+    public int timeout() {
+        return timeout;
+    }
+
+    @Override
+    public boolean permanent() {
+        return permanent;
+    }
+
+    @Override
+    public Operation op() {
+        return op;
+    }
+
+    /**
+     * Returns a new builder.
+     *
+     * @return new builder
+     */
+    public static Builder builder() {
+        return new Builder();
+    }
+
+
+    public static final class Builder implements FilteringObjective.Builder {
+        private final ImmutableList.Builder<Criterion> listBuilder
+                = ImmutableList.builder();
+
+        private Criterion key;
+        private boolean permanent = DEFAULT_PERMANENT;
+        private int timeout = DEFAULT_TIMEOUT;
+        private ApplicationId appId;
+        private int priority = DEFAULT_PRIORITY;
+
+        @Override
+        public Builder addCondition(Criterion criterion) {
+            listBuilder.add(criterion);
+            return this;
+        }
+
+        @Override
+        public Builder withKey(Criterion criterion) {
+            key = criterion;
+            return this;
+        }
+
+        @Override
+        public Builder makeTemporary(int timeout) {
+            this.timeout = timeout;
+            permanent = false;
+            return this;
+        }
+
+        @Override
+        public Builder makePermanent() {
+            permanent = true;
+            return this;
+        }
+
+        @Override
+        public Builder fromApp(ApplicationId appId) {
+            this.appId = appId;
+            return this;
+        }
+
+        @Override
+        public Builder withPriority(int priority) {
+            this.priority = priority;
+            return this;
+        }
+
+        @Override
+        public FilteringObjective add() {
+            List<Criterion> conditions = listBuilder.build();
+            checkNotNull(key, "Must have a key.");
+            checkArgument(!conditions.isEmpty(), "Must have at least one condition.");
+            checkNotNull(appId, "Must supply an application id");
+
+            return new DefaultFilteringObjective(key, permanent, timeout,
+                                                appId, priority, conditions,
+                                                Operation.ADD);
+
+        }
+
+        @Override
+        public FilteringObjective remove() {
+            List<Criterion> conditions = listBuilder.build();
+            checkNotNull(key, "Must have a key.");
+            checkArgument(!conditions.isEmpty(), "Must have at least one condition.");
+            checkNotNull(appId, "Must supply an application id");
+
+            return new DefaultFilteringObjective(key, permanent, timeout,
+                                                 appId, priority, conditions,
+                                                 Operation.REMOVE);
+
+        }
+
+
+    }
+
+}