add FirstNetwork, in line with FirstRegion, etc., for use in FGCP provider

core/src/main/java/org/jclouds/location/suppliers/implicit/FirstNetwork.java

@@ -0,0 +1,67 @@
+/**
+ * Licensed to jclouds, Inc. (jclouds) under one or more
+ * contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  jclouds licenses this file
+ * to you 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.jclouds.location.suppliers.implicit;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static com.google.common.collect.Iterables.find;
+import static com.google.common.collect.Iterables.transform;
+import static org.jclouds.location.predicates.LocationPredicates.isNetwork;
+
+import java.util.NoSuchElementException;
+import java.util.Set;
+
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+import org.jclouds.collect.Memoized;
+import org.jclouds.domain.Location;
+import org.jclouds.location.functions.ToIdAndScope;
+import org.jclouds.location.suppliers.ImplicitLocationSupplier;
+
+import com.google.common.base.Supplier;
+
+/**
+ * 
+ * @author Dies Koper
+ * 
+ */
+@Singleton
+public class FirstNetwork implements ImplicitLocationSupplier {
+
+    private final Supplier<Set<? extends Location>> locationsSupplier;
+
+    @Inject
+    FirstNetwork(@Memoized Supplier<Set<? extends Location>> locationsSupplier) {
+        this.locationsSupplier = checkNotNull(locationsSupplier,
+                "locationsSupplierSupplier");
+    }
+
+    @Override
+    public Location get() {
+        Set<? extends Location> locations = locationsSupplier.get();
+        try {
+            return find(locations, isNetwork());
+        } catch (NoSuchElementException e) {
+            throw new NoSuchElementException(
+                    "none of the locations are scope NETWORK: "
+                            + transform(locations, ToIdAndScope.INSTANCE));
+        }
+    }
+
+}

core/src/test/java/org/jclouds/location/suppliers/implicit/FirstNetworkTest.java

@@ -0,0 +1,71 @@
+/**
+ * Licensed to jclouds, Inc. (jclouds) under one or more
+ * contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  jclouds licenses this file
+ * to you 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.jclouds.location.suppliers.implicit;
+
+import static org.testng.Assert.assertEquals;
+
+import java.util.NoSuchElementException;
+import java.util.Set;
+
+import org.jclouds.domain.Location;
+import org.jclouds.domain.LocationBuilder;
+import org.jclouds.domain.LocationScope;
+import org.testng.annotations.Test;
+
+import com.google.common.base.Supplier;
+import com.google.common.base.Suppliers;
+import com.google.common.collect.ImmutableSet;
+
+/**
+ * Tests behavior of {@code FirstNetwork}
+ * 
+ * @author Adrian Cole
+ * @author Dies Koper
+ */
+@Test(groups = "unit", testName = "FirstNetworkTest")
+public class FirstNetworkTest {
+   Location provider = new LocationBuilder().scope(LocationScope.PROVIDER).id("servo").description("http://servo")
+         .build();
+   Location region = new LocationBuilder().scope(LocationScope.REGION).id("servo-r").description("http://r.servo")
+         .parent(provider).build();
+   Location network = new LocationBuilder().scope(LocationScope.NETWORK).id("servo-n").description("http://z.r.servo")
+         .parent(region).build();
+
+   @Test
+   public void testDidntFindNetworkThrowsNSEEWithReasonableMessage() {
+      Supplier<Set<? extends Location>> supplier = Suppliers.<Set<? extends Location>> ofInstance(ImmutableSet
+            .<Location> of(provider, region));
+      FirstNetwork fn = new FirstNetwork(supplier);
+
+      try {
+         fn.get();
+         assert false;
+      } catch (NoSuchElementException e) {
+         assertEquals(e.getMessage(), "none of the locations are scope NETWORK: [servo:PROVIDER, servo-r:REGION]");
+      }
+   }
+
+   @Test
+   public void testFirstNetwork() {
+      Supplier<Set<? extends Location>> supplier = Suppliers.<Set<? extends Location>> ofInstance(ImmutableSet
+            .<Location> of(provider, region, network));
+      FirstNetwork fn = new FirstNetwork(supplier);
+      assertEquals(fn.get(), network);
+   }
+}