Allow overrides of standard commands

spring-shell-samples/src/main/java/org/springframework/shell/samples/SpringShellSample.java

@@ -40,6 +40,6 @@ import org.springframework.shell.result.ResultHandlerConfig;
 public class SpringShellSample {
 
 	public static void main(String[] args) throws Exception {
-		ConfigurableApplicationContext context = SpringApplication.run(SpringShellSample.class);
+		ConfigurableApplicationContext context = SpringApplication.run(SpringShellSample.class, args);
 	}
 }

spring-shell-standard-commands/src/main/java/org/springframework/shell/standard/commands/Clear.java

@@ -30,7 +30,20 @@ import org.springframework.shell.standard.ShellMethod;
  * @author Eric Bottard
  */
 @ShellComponent
-public class Console {
+public class Clear {
+
+	/**
+	 * Marker interface for beans providing {@literal clear} functionality to the shell.
+	 *
+	 * <p>To override the clear command, simply register your own bean implementing that interface
+	 * and the standard implementation will back off.</p>
+	 *
+	 * <p>To disable the {@literal clear} command entirely, set the {@literal spring.shell.command.clear.enabled=false}
+	 * property in the environment.</p>
+	 *
+	 * @author Eric Bottard
+	 */
+	public interface Command {}
 
 	@Autowired @Lazy
 	private Terminal terminal;

spring-shell-standard-commands/src/main/java/org/springframework/shell/standard/commands/Help.java

@@ -49,6 +49,19 @@ import org.springframework.shell.Utils;
 @ShellComponent
 public class Help {
 
+	/**
+	 * Marker interface for beans providing {@literal help} functionality to the shell.
+	 *
+	 * <p>To override the help command, simply register your own bean implementing that interface
+	 * and the standard implementation will back off.</p>
+	 *
+	 * <p>To disable the {@literal help} command entirely, set the {@literal spring.shell.command.help.enabled=false}
+	 * property in the environment.</p>
+	 *
+	 * @author Eric Bottard
+	 */
+	public interface Command {}
+
 	private final List<ParameterResolver> parameterResolvers;
 
 	private CommandRegistry commandRegistry;

spring-shell-standard-commands/src/main/java/org/springframework/shell/standard/commands/Quit.java

@@ -28,6 +28,19 @@ import org.springframework.shell.standard.ShellMethod;
 @ShellComponent
 public class Quit {
 
+	/**
+	 * Marker interface for beans providing {@literal quit} functionality to the shell.
+	 *
+	 * <p>To override the quit command, simply register your own bean implementing that interface
+	 * and the standard implementation will back off.</p>
+	 *
+	 * <p>To disable the {@literal quit} command entirely, set the {@literal spring.shell.command.quit.enabled=false}
+	 * property in the environment.</p>
+	 *
+	 * @author Eric Bottard
+	 */
+	public interface Command {}
+
 	@ShellMethod(help = "Exit the shell.", value = {"quit", "exit"})
 	public void quit() {
 		throw new ExitRequest();

spring-shell-standard-commands/src/main/java/org/springframework/shell/standard/commands/Stacktrace.java

@@ -30,6 +30,19 @@ import org.springframework.shell.standard.ShellMethod;
 @ShellComponent
 public class Stacktrace {
 
+	/**
+	 * Marker interface for beans providing {@literal stacktrace} functionality to the shell.
+	 *
+	 * <p>To override the stacktrace command, simply register your own bean implementing that interface
+	 * and the standard implementation will back off.</p>
+	 *
+	 * <p>To disable the {@literal stacktrace} command entirely, set the {@literal spring.shell.command.stacktrace.enabled=false}
+	 * property in the environment.</p>
+	 *
+	 * @author Eric Bottard
+	 */
+	public interface Command {}
+
 	@Autowired @Lazy
 	private Terminal terminal;
 

spring-shell-standard-commands/src/main/java/org/springframework/shell/standard/commands/StandardCommandsAutoConfiguration.java

@@ -18,6 +18,8 @@ package org.springframework.shell.standard.commands;
 
 import java.util.List;
 
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.shell.ParameterResolver;
@@ -31,21 +33,29 @@ import org.springframework.shell.ParameterResolver;
 public class StandardCommandsAutoConfiguration {
 
 	@Bean
+	@ConditionalOnMissingBean(Help.Command.class)
+	@ConditionalOnProperty(prefix = "spring.shell.command.help", value = "enabled", havingValue = "true", matchIfMissing = true)
 	public Help help(List<ParameterResolver> parameterResolvers) {
 		return new Help(parameterResolvers);
 	}
 
 	@Bean
-	public Console console() {
-		return new Console();
+	@ConditionalOnMissingBean(Clear.Command.class)
+	@ConditionalOnProperty(prefix = "spring.shell.command.clear", value = "enabled", havingValue = "true", matchIfMissing = true)
+	public Clear clear() {
+		return new Clear();
 	}
 
 	@Bean
+	@ConditionalOnMissingBean(Quit.Command.class)
+	@ConditionalOnProperty(prefix = "spring.shell.command.quit", value = "enabled", havingValue = "true", matchIfMissing = true)
 	public Quit quit() {
 		return new Quit();
 	}
 
 	@Bean
+	@ConditionalOnMissingBean(Stacktrace.Command.class)
+	@ConditionalOnProperty(prefix = "spring.shell.command.stacktrace", value = "enabled", havingValue = "true", matchIfMissing = true)
 	public Stacktrace stacktrace() {
 		return new Stacktrace();
 	}