Extract some code samples from docs

See gh-6313

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/externalizedconfiguration/constructorbinding/AcmeProperties.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.externalizedconfiguration.constructorbinding;
+
+//tag::code[]
+import java.net.InetAddress;
+import java.util.List;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.context.properties.ConstructorBinding;
+import org.springframework.boot.context.properties.bind.DefaultValue;
+
+@ConstructorBinding
+@ConfigurationProperties("acme")
+public class AcmeProperties {
+
+	private final boolean enabled;
+
+	private final InetAddress remoteAddress;
+
+	private final Security security;
+
+	public AcmeProperties(boolean enabled, InetAddress remoteAddress, Security security) {
+		this.enabled = enabled;
+		this.remoteAddress = remoteAddress;
+		this.security = security;
+	}
+
+	public boolean isEnabled() {
+		return this.enabled;
+	}
+
+	public InetAddress getRemoteAddress() {
+		return this.remoteAddress;
+	}
+
+	public Security getSecurity() {
+		return this.security;
+	}
+
+	public static class Security {
+
+		private final String username;
+
+		private final String password;
+
+		private final List<String> roles;
+
+		public Security(String username, String password, @DefaultValue("USER") List<String> roles) {
+			this.username = username;
+			this.password = password;
+			this.roles = roles;
+		}
+
+		public String getUsername() {
+			return this.username;
+		}
+
+		public String getPassword() {
+			return this.password;
+		}
+
+		public List<String> getRoles() {
+			return this.roles;
+		}
+
+	}
+
+}
+// end::code[]

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/externalizedconfiguration/constructorbinding/nonnull/AcmeProperties.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.externalizedconfiguration.constructorbinding.nonnull;
+
+import java.net.InetAddress;
+import java.util.List;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.context.properties.ConstructorBinding;
+import org.springframework.boot.context.properties.bind.DefaultValue;
+
+@ConstructorBinding
+@ConfigurationProperties("acme")
+public class AcmeProperties {
+
+	private final boolean enabled;
+
+	private final InetAddress remoteAddress;
+
+	private final Security security;
+
+	// tag::code[]
+	public AcmeProperties(boolean enabled, InetAddress remoteAddress, @DefaultValue Security security) {
+		this.enabled = enabled;
+		this.remoteAddress = remoteAddress;
+		this.security = security;
+	}
+	// end::code[]
+
+	public boolean isEnabled() {
+		return this.enabled;
+	}
+
+	public InetAddress getRemoteAddress() {
+		return this.remoteAddress;
+	}
+
+	public Security getSecurity() {
+		return this.security;
+	}
+
+	public static class Security {
+
+		private final String username;
+
+		private final String password;
+
+		private final List<String> roles;
+
+		public Security(String username, String password, @DefaultValue("USER") List<String> roles) {
+			this.username = username;
+			this.password = password;
+			this.roles = roles;
+		}
+
+		public String getUsername() {
+			return this.username;
+		}
+
+		public String getPassword() {
+			return this.password;
+		}
+
+		public List<String> getRoles() {
+			return this.roles;
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/externalizedconfiguration/javabeanbinding/AcmeProperties.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.externalizedconfiguration.javabeanbinding;
+
+//tag::code[]
+import java.net.InetAddress;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+@ConfigurationProperties("acme")
+public class AcmeProperties {
+
+	private boolean enabled;
+
+	private InetAddress remoteAddress;
+
+	private final Security security = new Security();
+
+	public boolean isEnabled() {
+		return this.enabled;
+	}
+
+	public void setEnabled(boolean enabled) {
+		this.enabled = enabled;
+	}
+
+	public InetAddress getRemoteAddress() {
+		return this.remoteAddress;
+	}
+
+	public void setRemoteAddress(InetAddress remoteAddress) {
+		this.remoteAddress = remoteAddress;
+	}
+
+	public Security getSecurity() {
+		return this.security;
+	}
+
+	public static class Security {
+
+		private String username;
+
+		private String password;
+
+		private List<String> roles = new ArrayList<>(Collections.singleton("USER"));
+
+		public String getUsername() {
+			return this.username;
+		}
+
+		public void setUsername(String username) {
+			this.username = username;
+		}
+
+		public String getPassword() {
+			return this.password;
+		}
+
+		public void setPassword(String password) {
+			this.password = password;
+		}
+
+		public List<String> getRoles() {
+			return this.roles;
+		}
+
+		public void setRoles(List<String> roles) {
+			this.roles = roles;
+		}
+
+	}
+
+}
+// end::code[]

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/externalizedconfiguration/valueinjection/MyBean.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.externalizedconfiguration.valueinjection;
+
+// tag::code[]
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+@Component
+public class MyBean {
+
+	@Value("${name}")
+	private String name;
+
+	// ...
+
+}
+// end::code[]

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/springapplication/ApplicationArgumentsExample.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.springapplication;
+
+//tag::code[]
+import java.util.List;
+
+import org.springframework.boot.ApplicationArguments;
+import org.springframework.stereotype.Component;
+
+@Component
+public class ApplicationArgumentsExample {
+
+	public ApplicationArgumentsExample(ApplicationArguments args) {
+		boolean debug = args.containsOption("debug");
+		List<String> files = args.getNonOptionArgs();
+		if (debug) {
+			System.out.println(files);
+		}
+		// if run with "--debug logfile.txt" prints ["logfile.txt"]
+	}
+
+}
+// end::code[]

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/springapplication/CommandLineRunnerExample.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.springapplication;
+
+//tag::code[]
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.stereotype.Component;
+
+@Component
+public class CommandLineRunnerExample implements CommandLineRunner {
+
+	@Override
+	public void run(String... args) {
+		// Do something...
+	}
+
+}
+// end::code[]

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/springapplication/availability/LocalCacheVerifier.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.springapplication.availability;
+
+//tag::code[]
+import org.springframework.boot.availability.AvailabilityChangeEvent;
+import org.springframework.boot.availability.LivenessState;
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.stereotype.Component;
+
+@Component
+public class LocalCacheVerifier {
+
+	private final ApplicationEventPublisher eventPublisher;
+
+	public LocalCacheVerifier(ApplicationEventPublisher eventPublisher) {
+		this.eventPublisher = eventPublisher;
+	}
+
+	public void checkLocalCache() {
+		try {
+			// ...
+		}
+		catch (CacheCompletelyBrokenException ex) {
+			AvailabilityChangeEvent.publish(this.eventPublisher, ex, LivenessState.BROKEN);
+		}
+	}
+
+}
+// end::code[]
+
+class CacheCompletelyBrokenException extends RuntimeException {
+
+}

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/springapplication/availability/ReadinessStateExporter.java

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+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.springapplication.availability;
+
+// tag::code[]
+import org.springframework.boot.availability.AvailabilityChangeEvent;
+import org.springframework.boot.availability.ReadinessState;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
+@Component
+public class ReadinessStateExporter {
+
+	@EventListener
+	public void onStateChange(AvailabilityChangeEvent<ReadinessState> event) {
+		switch (event.getState()) {
+		case ACCEPTING_TRAFFIC:
+			// create file /tmp/healthy
+			break;
+		case REFUSING_TRAFFIC:
+			// remove file /tmp/healthy
+			break;
+		}
+	}
+
+}
+// end::code[]

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/springapplication/main/custom/MyApplication.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.springapplication.main.custom;
+
+import org.springframework.boot.Banner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class MyApplication {
+
+	// tag::code[]
+	public static void main(String[] args) {
+		SpringApplication application = new SpringApplication(MyApplication.class);
+		application.setBannerMode(Banner.Mode.OFF);
+		application.run(args);
+	}
+	// end::code[]
+
+}

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/springapplication/main/run/MyApplication.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.springapplication.main.run;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class MyApplication {
+
+	// tag::code[]
+	public static void main(String[] args) {
+		SpringApplication.run(MyApplication.class, args);
+	}
+	// end::code[]
+
+}

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/springbootfeatures/springapplication/startup/MyApplication.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.springbootfeatures.springapplication.startup;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.metrics.buffering.BufferingApplicationStartup;
+
+@SpringBootApplication
+public class MyApplication {
+
+	// tag::code[]
+	public static void main(String[] args) {
+		SpringApplication application = new SpringApplication(MyApplication.class);
+		application.setApplicationStartup(new BufferingApplicationStartup(2048));
+		application.run(args);
+	}
+	// end::code[]
+
+}