Add detailed download reporting to AetherGrapeEngine

Groovy's Grape allows a user to enable download reports using the
system property groovy.grape.report.downloads. This commit updates
AetherGrapeEngine to honour this property and produce a detailed
download report when the system property is set to true. In the
absence of the system property, or when it's set to a value other than
true, the existing summary report is still produced.

[bs-344]
[60145094]

spring-boot-cli/src/test/java/org/springframework/boot/cli/compiler/grape/AetherGrapeEngineTests.java

@@ -92,7 +92,11 @@ public class AetherGrapeEngineTests {
 		Map<String, Object> args = new HashMap<String, Object>();
 		System.setProperty("disableSpringSnapshotRepos", "true");
 		try {
-			new AetherGrapeEngine(this.groovyClassLoader).grab(args,
+			AetherGrapeEngine aetherGrapeEngine = new AetherGrapeEngine(
+					this.groovyClassLoader);
+			aetherGrapeEngine.addResolver(createResolver("restlet.org",
+					"http://maven.restlet.org"));
+			aetherGrapeEngine.grab(args,
 					createDependency("org.springframework", "spring-jdbc", "3.2.0.M1"));
 		}
 		finally {

spring-boot-cli/src/test/java/org/springframework/boot/cli/compiler/grape/DetailedProgressReporterTests.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2012-2013 the original author or authors.
+ *
+ * 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.springframework.boot.cli.compiler.grape;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+
+import org.eclipse.aether.DefaultRepositorySystemSession;
+import org.eclipse.aether.transfer.TransferCancelledException;
+import org.eclipse.aether.transfer.TransferEvent;
+import org.eclipse.aether.transfer.TransferResource;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public final class DetailedProgressReporterTests {
+
+	private static final String REPOSITORY = "http://my.repository.com/";
+
+	private static final String ARTIFACT = "org/alpha/bravo/charlie/1.2.3/charlie-1.2.3.jar";
+
+	private final TransferResource resource = new TransferResource(REPOSITORY, ARTIFACT,
+			null, null);
+
+	private final ByteArrayOutputStream baos = new ByteArrayOutputStream();
+
+	private final PrintStream out = new PrintStream(this.baos);
+
+	private final DefaultRepositorySystemSession session = new DefaultRepositorySystemSession();
+
+	@Before
+	public void initialize() {
+		new DetailedProgressReporter(this.session, this.out);
+	}
+
+	@Test
+	public void downloading() throws TransferCancelledException {
+		TransferEvent startedEvent = new TransferEvent.Builder(this.session,
+				this.resource).build();
+		this.session.getTransferListener().transferStarted(startedEvent);
+
+		assertEquals(String.format("Downloading: %s%s%n", REPOSITORY, ARTIFACT),
+				new String(this.baos.toByteArray()));
+	}
+
+	@Test
+	public void downloaded() throws InterruptedException {
+		// Ensure some transfer time
+		Thread.sleep(100);
+
+		TransferEvent completedEvent = new TransferEvent.Builder(this.session,
+				this.resource).addTransferredBytes(4096).build();
+		this.session.getTransferListener().transferSucceeded(completedEvent);
+
+		assertTrue(new String(this.baos.toByteArray()).matches(String.format(
+				"Downloaded: %s%s \\(4KB at [0-9]+\\.[0-9]KB/sec\\)\\n", REPOSITORY,
+				ARTIFACT)));
+	}
+}