Add ApplicationArguments and ApplicationRunner

Add ApplicationArguments interface which allows SpringApplication.run
arguments to be injected into any bean. The interface provides access
to both the raw String[] arguments and also provides some convenience
methods to access the parsed 'option' and 'non-option' arguments.

A new ApplicationRunner interface has also been added which is
similar to the existing CommandLineRunner.

Fixes gh-1990

spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -184,12 +184,49 @@ TIP: It is often desirable to call `setWebEnvironment(false)` when using
 
 
 
+[[boot-features-application-arguments]]
+=== Accessing application arguments
+If you need to access the application arguments that were passed to
+`SpringApplication.run(...)` you can inject a
+`org.springframework.boot.ApplicationArguments` bean. The `ApplicationArguments` interface
+provides access to both the raw `String[]` arguments as well as parsed `option` and
+`non-option` arguments:
+
+[source,java,indent=0]
+----
+	import org.springframework.boot.*
+	import org.springframework.beans.factory.annotation.*
+	import org.springframework.stereotype.*
+
+	@Component
+	public class MyBean {
+
+		@Autowired
+		public MyBean(ApplicationArguments args) {
+			boolean debug = args.containsOption("debug");
+			List<String> files = args.getNonOptionArgs();
+			// if run with "--debug logfile.txt" debug=true, files=["logfile.txt"]
+		}
+
+	}
+----
+
+TIP: Spring Boot will also register a `CommandLinePropertySource` with the Spring
+`Environment`. This allows you to also inject single application arguments using the
+`@Value` annotation.
+
+
+
 [[boot-features-command-line-runner]]
-=== Using the CommandLineRunner
-If you want access to the raw command line arguments, or you need to run some specific
-code once the `SpringApplication` has started you can implement the `CommandLineRunner`
-interface. The `run(String... args)` method will be called on all Spring beans
-implementing this interface.
+=== Using the ApplicationRunner or CommandLineRunner
+If you need to run some specific code once the `SpringApplication` has started, you can
+implement the `ApplicationRunner` or `CommandLineRunner` interfaces. Both interfaces work
+in the same way and offer a single `run` method which will be called just before
+`SpringApplication.run(...)` completes.
+
+The `CommandLineRunner` interfaces provides access to application arguments as a simple
+string array, whereas the `ApplicationRunner` uses the `ApplicationArguments` interface
+discussed above.
 
 [source,java,indent=0]
 ----
@@ -199,16 +236,16 @@ implementing this interface.
 	@Component
 	public class MyBean implements CommandLineRunner {
 
-	    public void run(String... args) {
-	        // Do something...
-	    }
+		public void run(String... args) {
+			// Do something...
+		}
 
 	}
 ----
 
 You can additionally implement the `org.springframework.core.Ordered` interface or use the
-`org.springframework.core.annotation.Order` annotation if several `CommandLineRunner`
-beans are defined that must be called in a specific order.
+`org.springframework.core.annotation.Order` annotation if several `CommandLineRunner` or
+`ApplicationRunner` beans are defined that must be called in a specific order.
 
 
 

spring-boot/src/main/java/org/springframework/boot/ApplicationArguments.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2012-2015 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;
+
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Provides access to the arguments that were used run a {@link SpringApplication}.
+ *
+ * @author Phillip Webb
+ * @since 1.3.0
+ */
+public interface ApplicationArguments {
+
+	/**
+	 * Return the raw unprocessed arguments that were passed to the application.
+	 * @return the arguments
+	 */
+	public String[] getSourceArgs();
+
+	/**
+	 * Return then names of all option arguments. For example, if the arguments were
+	 * "--foo=bar --debug" would return the values {@code ["foo", "bar"]}.
+	 * @return the option names or an empty set
+	 */
+	public Set<String> getOptionNames();
+
+	/**
+	 * Return whether the set of option arguments parsed from the arguments contains an
+	 * option with the given name.
+	 * @param name the name to check
+	 * @return {@code true} if the arguments contains an option with the given name
+	 */
+	boolean containsOption(String name);
+
+	/**
+	 * Return the collection of values associated with the arguments option having the
+	 * given name.
+	 * <ul>
+	 * <li>if the option is present and has no argument (e.g.: "--foo"), return an empty
+	 * collection ({@code []})</li>
+	 * <li>if the option is present and has a single value (e.g. "--foo=bar"), return a
+	 * collection having one element ({@code ["bar"]})</li>
+	 * <li>if the option is present and has multiple values (e.g. "--foo=bar --foo=baz"),
+	 * return a collection having elements for each value ({@code ["bar", "baz"]})</li>
+	 * <li>if the option is not present, return {@code null}</li>
+	 * </ul>
+	 * @param name the name of the option
+	 * @return a list of option values for the given name
+	 */
+	List<String> getOptionValues(String name);
+
+	/**
+	 * Return the collection of non-option arguments parsed.
+	 * @return the non-option arguments or an empty list
+	 */
+	List<String> getNonOptionArgs();
+
+}

spring-boot/src/main/java/org/springframework/boot/ApplicationRunner.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2012-2015 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;
+
+import org.springframework.core.Ordered;
+import org.springframework.core.annotation.Order;
+
+/**
+ * Interface used to indicate that a bean should <em>run</em> when it is contained within
+ * a {@link SpringApplication}. Multiple {@link ApplicationArguments} beans can be defined
+ * within the same application context and can be ordered using the {@link Ordered}
+ * interface or {@link Order @Order} annotation.
+ *
+ * @author Phillip Webb
+ * @see CommandLineRunner
+ * @since 1.3.0
+ */
+public interface ApplicationRunner {
+
+	/**
+	 * Callback used to run the bean.
+	 * @param args incoming application arguments
+	 * @throws Exception on error
+	 */
+	void run(ApplicationArguments args) throws Exception;
+
+}

spring-boot/src/main/java/org/springframework/boot/CommandLineRunner.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2013 the original author or authors.
+ * Copyright 2012-2015 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.
@@ -24,8 +24,12 @@ import org.springframework.core.annotation.Order;
  * a {@link SpringApplication}. Multiple {@link CommandLineRunner} beans can be defined
  * within the same application context and can be ordered using the {@link Ordered}
  * interface or {@link Order @Order} annotation.
+ * <p>
+ * If you need access to {@link ApplicationArguments} instead of the raw String array
+ * consider using {@link ApplicationRunner}.
  *
  * @author Dave Syer
+ * @see ApplicationRunner
  */
 public interface CommandLineRunner {
 

spring-boot/src/main/java/org/springframework/boot/DefaultApplicationArguments.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2012-2015 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;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.springframework.core.env.SimpleCommandLinePropertySource;
+import org.springframework.util.Assert;
+
+/**
+ * Default internal implementation of {@link ApplicationArguments}.
+ *
+ * @author Phillip Webb
+ */
+class DefaultApplicationArguments implements ApplicationArguments {
+
+	private final Source source;
+
+	private final String[] args;
+
+	public DefaultApplicationArguments(String[] args) {
+		Assert.notNull(args, "Args must not be null");
+		this.source = new Source(args);
+		this.args = args;
+	}
+
+	@Override
+	public String[] getSourceArgs() {
+		return this.args;
+	}
+
+	@Override
+	public Set<String> getOptionNames() {
+		String[] names = this.source.getPropertyNames();
+		return Collections.unmodifiableSet(new HashSet<String>(Arrays.asList(names)));
+	}
+
+	@Override
+	public boolean containsOption(String name) {
+		return this.source.containsProperty(name);
+	}
+
+	@Override
+	public List<String> getOptionValues(String name) {
+		List<String> values = this.source.getOptionValues(name);
+		return (values == null ? null : Collections.unmodifiableList(values));
+	}
+
+	@Override
+	public List<String> getNonOptionArgs() {
+		return this.source.getNonOptionArgs();
+	}
+
+	private static class Source extends SimpleCommandLinePropertySource {
+
+		public Source(String[] args) {
+			super(args);
+		}
+
+		@Override
+		public List<String> getNonOptionArgs() {
+			return super.getNonOptionArgs();
+		}
+
+		@Override
+		public List<String> getOptionValues(String name) {
+			return super.getOptionValues(name);
+		}
+
+	}
+
+}

spring-boot/src/main/java/org/springframework/boot/SpringApplication.java

@@ -271,7 +271,6 @@ public class SpringApplication {
 		listeners.started();
 		try {
 			context = doRun(listeners, args);
-
 			stopWatch.stop();
 			if (this.logStartupInfo) {
 				new StartupInfoLogger(this.mainApplicationClass).logStarted(
@@ -328,6 +327,11 @@ public class SpringApplication {
 			logStartupInfo(context.getParent() == null);
 		}
 
+		// Add boot specific singleton beans
+		ApplicationArguments applicationArguments = new DefaultApplicationArguments(args);
+		context.getBeanFactory().registerSingleton("springApplicationArguments",
+				applicationArguments);
+
 		// Load the sources
 		Set<Object> sources = getSources();
 		Assert.notEmpty(sources, "Sources must not be empty");
@@ -336,7 +340,7 @@ public class SpringApplication {
 
 		// Refresh the context
 		refresh(context);
-		afterRefresh(context, args);
+		afterRefresh(context, applicationArguments);
 		listeners.finished(context, null);
 		return context;
 	}
@@ -654,20 +658,6 @@ public class SpringApplication {
 		return new BeanDefinitionLoader(registry, sources);
 	}
 
-	private void runCommandLineRunners(ApplicationContext context, String... args) {
-		List<CommandLineRunner> runners = new ArrayList<CommandLineRunner>(context
-				.getBeansOfType(CommandLineRunner.class).values());
-		AnnotationAwareOrderComparator.sort(runners);
-		for (CommandLineRunner runner : runners) {
-			try {
-				runner.run(args);
-			}
-			catch (Exception ex) {
-				throw new IllegalStateException("Failed to execute CommandLineRunner", ex);
-			}
-		}
-	}
-
 	/**
 	 * Refresh the underlying {@link ApplicationContext}.
 	 * @param applicationContext the application context to refresh
@@ -677,8 +667,59 @@ public class SpringApplication {
 		((AbstractApplicationContext) applicationContext).refresh();
 	}
 
+	/**
+	 * Called after the context has been refreshed.
+	 * @param context the application context
+	 * @param args the application argumments
+	 */
+	protected void afterRefresh(ConfigurableApplicationContext context,
+			ApplicationArguments args) {
+		afterRefresh(context, args.getSourceArgs());
+		callRunners(context, args);
+	}
+
+	private void callRunners(ApplicationContext context, ApplicationArguments args) {
+		List<Object> runners = new ArrayList<Object>();
+		runners.addAll(context.getBeansOfType(ApplicationRunner.class).values());
+		runners.addAll(context.getBeansOfType(CommandLineRunner.class).values());
+		AnnotationAwareOrderComparator.sort(runners);
+		for (Object runner : new LinkedHashSet<Object>(runners)) {
+			if (runner instanceof ApplicationRunner) {
+				callRunner((ApplicationRunner) runner, args);
+			}
+			if (runner instanceof CommandLineRunner) {
+				callRunner((CommandLineRunner) runner, args);
+			}
+		}
+	}
+
+	private void callRunner(ApplicationRunner runner, ApplicationArguments args) {
+		try {
+			(runner).run(args);
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException("Failed to execute ApplicationRunner", ex);
+		}
+	}
+
+	private void callRunner(CommandLineRunner runner, ApplicationArguments args) {
+		try {
+			(runner).run(args.getSourceArgs());
+		}
+		catch (Exception ex) {
+			throw new IllegalStateException("Failed to execute CommandLineRunner", ex);
+		}
+	}
+
+	/**
+	 * Called after the context has been refreshed.
+	 * @param context the application context
+	 * @param args the application argumments
+	 * @deprecated in 1.3 in favor of
+	 * {@link #afterRefresh(ConfigurableApplicationContext, ApplicationArguments)}
+	 */
+	@Deprecated
 	protected void afterRefresh(ConfigurableApplicationContext context, String[] args) {
-		runCommandLineRunners(context, args);
 	}
 
 	/**

spring-boot/src/test/java/org/springframework/boot/DefaultApplicationArgumentsTests.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright 2012-2015 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;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Set;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Tests for {@link DefaultApplicationArguments}.
+ *
+ * @author Phillip Webb
+ */
+public class DefaultApplicationArgumentsTests {
+
+	private static final String[] ARGS = new String[] { "--foo=bar", "--foo=baz",
+			"--debug", "spring", "boot" };
+
+	@Rule
+	public ExpectedException thrown = ExpectedException.none();
+
+	@Test
+	public void argumentsMustNoBeNull() throws Exception {
+		this.thrown.expect(IllegalArgumentException.class);
+		this.thrown.expectMessage("Args must not be null");
+		new DefaultApplicationArguments(null);
+	}
+
+	@Test
+	public void getArgs() throws Exception {
+		ApplicationArguments arguments = new DefaultApplicationArguments(ARGS);
+		assertThat(arguments.getSourceArgs(), equalTo(ARGS));
+	}
+
+	@Test
+	public void optionNames() throws Exception {
+		ApplicationArguments arguments = new DefaultApplicationArguments(ARGS);
+		Set<String> expected = new HashSet<String>(Arrays.asList("foo", "debug"));
+		assertThat(arguments.getOptionNames(), equalTo(expected));
+	}
+
+	@Test
+	public void containsOption() throws Exception {
+		ApplicationArguments arguments = new DefaultApplicationArguments(ARGS);
+		assertThat(arguments.containsOption("foo"), equalTo(true));
+		assertThat(arguments.containsOption("debug"), equalTo(true));
+		assertThat(arguments.containsOption("spring"), equalTo(false));
+	}
+
+	@Test
+	public void getOptionValues() throws Exception {
+		ApplicationArguments arguments = new DefaultApplicationArguments(ARGS);
+		assertThat(arguments.getOptionValues("foo"), equalTo(Arrays.asList("bar", "baz")));
+		assertThat(arguments.getOptionValues("debug"),
+				equalTo(Collections.<String> emptyList()));
+		assertThat(arguments.getOptionValues("spring"), equalTo(null));
+	}
+
+	@Test
+	public void getNonOptionArgs() throws Exception {
+		ApplicationArguments arguments = new DefaultApplicationArguments(ARGS);
+		assertThat(arguments.getNonOptionArgs(), equalTo(Arrays.asList("spring", "boot")));
+	}
+
+	@Test
+	public void getNoNonOptionArgs() throws Exception {
+		ApplicationArguments arguments = new DefaultApplicationArguments(
+				new String[] { "--debug" });
+		assertThat(arguments.getNonOptionArgs(),
+				equalTo(Collections.<String> emptyList()));
+	}
+
+}

spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java

@@ -442,12 +442,13 @@ public class SpringApplicationTests {
 	}
 
 	@Test
-	public void runCommandLineRunners() throws Exception {
+	public void runCommandLineRunnersAndApplicationRunners() throws Exception {
 		SpringApplication application = new SpringApplication(CommandLineRunConfig.class);
 		application.setWebEnvironment(false);
 		this.context = application.run("arg");
 		assertTrue(this.context.getBean("runnerA", TestCommandLineRunner.class).hasRun());
-		assertTrue(this.context.getBean("runnerB", TestCommandLineRunner.class).hasRun());
+		assertTrue(this.context.getBean("runnerB", TestApplicationRunner.class).hasRun());
+		assertTrue(this.context.getBean("runnerC", TestCommandLineRunner.class).hasRun());
 	}
 
 	@Test
@@ -604,6 +605,16 @@ public class SpringApplicationTests {
 		assertThat(System.getProperty("java.awt.headless"), equalTo("false"));
 	}
 
+	@Test
+	public void getApplicationArgumentsBean() throws Exception {
+		TestSpringApplication application = new TestSpringApplication(ExampleConfig.class);
+		application.setWebEnvironment(false);
+		this.context = application.run("--debug", "spring", "boot");
+		ApplicationArguments args = this.context.getBean(ApplicationArguments.class);
+		assertThat(args.getNonOptionArgs(), equalTo(Arrays.asList("spring", "boot")));
+		assertThat(args.containsOption("debug"), equalTo(true));
+	}
+
 	private boolean hasPropertySource(ConfigurableEnvironment environment,
 			Class<?> propertySourceClass, String name) {
 		for (PropertySource<?> source : environment.getPropertySources()) {
@@ -715,8 +726,14 @@ public class SpringApplicationTests {
 	static class CommandLineRunConfig {
 
 		@Bean
-		public TestCommandLineRunner runnerB() {
-			return new TestCommandLineRunner(Ordered.LOWEST_PRECEDENCE, "runnerA");
+		public TestCommandLineRunner runnerC() {
+			return new TestCommandLineRunner(Ordered.LOWEST_PRECEDENCE, "runnerB",
+					"runnerA");
+		}
+
+		@Bean
+		public TestApplicationRunner runnerB() {
+			return new TestApplicationRunner(Ordered.LOWEST_PRECEDENCE - 1, "runnerA");
 		}
 
 		@Bean
@@ -725,18 +742,17 @@ public class SpringApplicationTests {
 		}
 	}
 
-	static class TestCommandLineRunner implements CommandLineRunner,
-			ApplicationContextAware, Ordered {
+	static class AbstractTestRunner implements ApplicationContextAware, Ordered {
 
 		private final String[] expectedBefore;
 
 		private ApplicationContext applicationContext;
 
-		private String[] args;
-
 		private final int order;
 
-		public TestCommandLineRunner(int order, String... expectedBefore) {
+		private boolean run;
+
+		public AbstractTestRunner(int order, String... expectedBefore) {
 			this.expectedBefore = expectedBefore;
 			this.order = order;
 		}
@@ -752,18 +768,45 @@ public class SpringApplicationTests {
 			return this.order;
 		}
 
-		@Override
-		public void run(String... args) {
-			this.args = args;
+		public void markAsRan() {
+			this.run = true;
 			for (String name : this.expectedBefore) {
-				TestCommandLineRunner bean = this.applicationContext.getBean(name,
-						TestCommandLineRunner.class);
+				AbstractTestRunner bean = this.applicationContext.getBean(name,
+						AbstractTestRunner.class);
 				assertTrue(bean.hasRun());
 			}
 		}
 
 		public boolean hasRun() {
-			return this.args != null;
+			return this.run;
+		}
+
+	}
+
+	private static class TestCommandLineRunner extends AbstractTestRunner implements
+			CommandLineRunner {
+
+		public TestCommandLineRunner(int order, String... expectedBefore) {
+			super(order, expectedBefore);
+		}
+
+		@Override
+		public void run(String... args) {
+			markAsRan();
+		}
+
+	}
+
+	private static class TestApplicationRunner extends AbstractTestRunner implements
+			ApplicationRunner {
+
+		public TestApplicationRunner(int order, String... expectedBefore) {
+			super(order, expectedBefore);
+		}
+
+		@Override
+		public void run(ApplicationArguments args) {
+			markAsRan();
 		}
 
 	}