Refactor dependencies to avoid package tangles

Fixes #37

spring-shell2-core/src/main/java/org/springframework/shell2/Bootstrap.java

@@ -40,7 +40,6 @@ import org.springframework.shell2.standard.StandardParameterResolver;
  * @author Camilo Gonzalez
  */
 @SpringBootApplication
-@ComponentScan(basePackageClasses = Bootstrap.class)
 public class Bootstrap {
 
 	public static void main(String[] args) throws Exception {
@@ -53,18 +52,9 @@ public class Bootstrap {
 		return new DefaultConversionService();
 	}
 
-	@Bean
-	public ParameterResolver parameterResolver(ConversionService conversionService) {
-		return new StandardParameterResolver(conversionService);
-	}
-
 	@Bean
 	public Terminal terminal() throws IOException {
 		return TerminalBuilder.builder().build();
 	}
 
-	@Bean
-	public EnumValueProvider enumValueProvider() {
-		return new EnumValueProvider();
-	}
 }

spring-shell2-core/src/main/java/org/springframework/shell2/JLineShell.java

@@ -46,8 +46,10 @@ import org.jline.utils.AttributedStringBuilder;
 import org.jline.utils.AttributedStyle;
 
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.context.ApplicationContext;
 import org.springframework.core.MethodParameter;
+import org.springframework.shell2.result.TypeHierarchyResultHandler;
 import org.springframework.stereotype.Component;
 import org.springframework.util.ReflectionUtils;
 
@@ -64,7 +66,8 @@ import org.springframework.util.ReflectionUtils;
 public class JLineShell implements Shell {
 
 	@Autowired
-	ResultHandlers resultHandlers = new ResultHandlers();
+	@Qualifier("main")
+	ResultHandler resultHandler;
 
 	@Autowired
 	private ApplicationContext applicationContext;
@@ -133,7 +136,7 @@ public class JLineShell implements Shell {
 			}
 			catch (UserInterruptException e) {
 				if (e.getPartialLine().isEmpty()) {
-					resultHandlers.handleResult(new ExitRequest(1));
+					resultHandler.handleResult(new ExitRequest(1));
 				} else {
 					continue;
 				}
@@ -171,7 +174,7 @@ public class JLineShell implements Shell {
 					result = e;
 				}
 
-				resultHandlers.handleResult(result);
+				resultHandler.handleResult(result);
 
 			}
 			else {

spring-shell2-core/src/main/java/org/springframework/shell2/ResultHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2017 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.
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.shell2.result;
+package org.springframework.shell2;
 
 /**
  * Implementations know how to deal with results of method invocations, whether normal results or exceptions thrown.

spring-shell2-core/src/main/java/org/springframework/shell2/result/AttributedCharSequenceResultHandler.java

@@ -20,6 +20,7 @@ import org.jline.terminal.Terminal;
 import org.jline.utils.AttributedCharSequence;
 
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.shell2.ResultHandler;
 import org.springframework.stereotype.Component;
 
 /**

spring-shell2-core/src/main/java/org/springframework/shell2/result/DefaultResultHandler.java

@@ -16,6 +16,7 @@
 
 package org.springframework.shell2.result;
 
+import org.springframework.shell2.ResultHandler;
 import org.springframework.stereotype.Component;
 
 /**

spring-shell2-core/src/main/java/org/springframework/shell2/result/ExitRequestResultHandler.java

@@ -22,6 +22,7 @@ import java.io.IOException;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ApplicationContext;
 import org.springframework.shell2.ExitRequest;
+import org.springframework.shell2.ResultHandler;
 import org.springframework.stereotype.Component;
 
 /**

spring-shell2-core/src/main/java/org/springframework/shell2/result/IterableResultHandler.java

@@ -17,29 +17,29 @@
 package org.springframework.shell2.result;
 
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.shell2.ResultHandlers;
+import org.springframework.shell2.ResultHandler;
 import org.springframework.stereotype.Component;
 
 /**
  * A {@link ResultHandler} that deals with {@link Iterable}s and delegates to
- * {@link ResultHandlers} for each element in turn.
+ * {@link TypeHierarchyResultHandler} for each element in turn.
  *
  * @author Eric Bottard
  */
 @Component
 public class IterableResultHandler implements ResultHandler<Iterable> {
 
-	private ResultHandlers resultHandlers;
+	private ResultHandler delegate;
 
-	@Autowired
-	public void setResultHandlers(ResultHandlers resultHandlers) {
-		this.resultHandlers = resultHandlers;
+	// Setter injection to avoid circular dependency at creation time
+	public void setDelegate(ResultHandler delegate) {
+		this.delegate = delegate;
 	}
 
 	@Override
 	public void handleResult(Iterable result) {
 		for (Object o : result) {
-			resultHandlers.handleResult(o);
+			delegate.handleResult(o);
 		}
 	}
 }

spring-shell2-core/src/main/java/org/springframework/shell2/result/ResultHandlerConfig.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2017 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.shell2.result;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.shell2.ResultHandler;
+
+/**
+ * Used for explicit configuration of {@link org.springframework.shell2.ResultHandler}s.
+ *
+ * @author Eric Bottard
+ */
+@Configuration
+public class ResultHandlerConfig {
+
+	@Bean
+	@Qualifier("main")
+	public ResultHandler<?> mainResultHandler() {
+		return new TypeHierarchyResultHandler();
+	}
+
+	@Bean
+	public IterableResultHandler iterableResultHandler() {
+		return new IterableResultHandler();
+	}
+
+	@PostConstruct
+	public void wireIterableResultHandler() {
+		iterableResultHandler().setDelegate(mainResultHandler());
+	}
+
+}

spring-shell2-core/src/main/java/org/springframework/shell2/result/ThrowableResultHandler.java

@@ -19,6 +19,7 @@ package org.springframework.shell2.result;
 import org.jline.utils.AttributedString;
 import org.jline.utils.AttributedStyle;
 
+import org.springframework.shell2.ResultHandler;
 import org.springframework.stereotype.Component;
 
 /**

spring-shell2-core/src/main/java/org/springframework/shell2/result/TypeHierarchyResultHandler.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.shell2;
+package org.springframework.shell2.result;
 
 import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
@@ -23,17 +23,20 @@ import java.util.Map;
 import java.util.Set;
 
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.shell2.result.ResultHandler;
+import org.springframework.shell2.ResultHandler;
 import org.springframework.stereotype.Component;
 
 /**
- * A unique entry point delegating to the most appropriate {@link ResultHandler},
- * according to the type of result to handle.
+ * A delegating {@link ResultHandler} that dispatches handling based on the type of the result.
+ * <p>
+ * If no direct match is found, the type hierarchy of the result is considered, including implemented interfaces.
+ * Auto-populates the handler map based on Generics type declaration of each discovered {@link ResultHandler} in the
+ * ApplicationContext.
+ * </p>
  *
  * @author Eric Bottard
  */
-@Component
-public class ResultHandlers {
+public class TypeHierarchyResultHandler implements ResultHandler<Object> {
 
 	private Map<Class<?>, ResultHandler<?>> resultHandlers = new HashMap<>();
 
@@ -67,7 +70,14 @@ public class ResultHandlers {
 	public void setResultHandlers(Set<ResultHandler<?>> resultHandlers) {
 		for (ResultHandler<?> resultHandler : resultHandlers) {
 			Type type = ((ParameterizedType) resultHandler.getClass().getGenericInterfaces()[0]).getActualTypeArguments()[0];
-			this.resultHandlers.put((Class<?>) type, resultHandler);
+			registerHandler((Class<?>) type, resultHandler);
+		}
+	}
+
+	private void registerHandler(Class<?> type, ResultHandler<?> resultHandler) {
+		ResultHandler<?> previous = this.resultHandlers.put(type, resultHandler);
+		if (previous != null) {
+			throw new IllegalArgumentException(String.format("Multiple ResultHandlers configured for %s: both %s and %s", type, previous, resultHandler));
 		}
 	}
 

spring-shell2-core/src/main/java/org/springframework/shell2/standard/EnumValueProvider.java

@@ -22,11 +22,13 @@ import java.util.List;
 import org.springframework.core.MethodParameter;
 import org.springframework.shell2.CompletionContext;
 import org.springframework.shell2.CompletionProposal;
+import org.springframework.stereotype.Component;
 
 /**
  * A {@link ValueProvider} that knows how to complete values for {@link Enum} typed parameters.
  * @author Eric Bottard
  */
+@Component
 public class EnumValueProvider implements ValueProvider {
 
 	@Override

spring-shell2-core/src/main/java/org/springframework/shell2/standard/StandardParameterResolver.java

@@ -45,6 +45,7 @@ import org.springframework.shell2.ParameterMissingResolutionException;
 import org.springframework.shell2.ParameterResolver;
 import org.springframework.shell2.UnfinishedParameterResolutionException;
 import org.springframework.shell2.Utils;
+import org.springframework.stereotype.Component;
 import org.springframework.util.Assert;
 import org.springframework.util.ConcurrentReferenceHashMap;
 
@@ -71,6 +72,7 @@ import org.springframework.util.ConcurrentReferenceHashMap;
  * @author Eric Bottard
  * @author Florent Biville
  */
+@Component
 public class StandardParameterResolver implements ParameterResolver {
 
 	private final ConversionService conversionService;
@@ -84,6 +86,7 @@ public class StandardParameterResolver implements ParameterResolver {
 	 */
 	private final Map<CacheKey, Map<Parameter, ParameterRawValue>> parameterCache = new ConcurrentReferenceHashMap<>();
 
+	@Autowired
 	public StandardParameterResolver(ConversionService conversionService) {
 		this.conversionService = conversionService;
 	}

spring-shell2-core/src/test/java/org/springframework/shell2/JLineShellTest.java

@@ -23,13 +23,13 @@ import org.jline.reader.UserInterruptException;
 import org.junit.Test;
 import org.mockito.Mockito;
 
-import org.springframework.shell2.result.ResultHandler;
-
 import static org.hamcrest.CoreMatchers.is;
 import static org.junit.Assert.assertThat;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
+import org.springframework.shell2.result.TypeHierarchyResultHandler;
+
 /**
  * Unit tests for {@link JLineShell}.
  *
@@ -43,7 +43,7 @@ public class JLineShellTest {
 	public void testCtrlCInterception() throws Exception {
 		shell.lineReader = mock(LineReader.class);
 		AssertingExitRequestResultHandler resultHandler = new AssertingExitRequestResultHandler();
-		shell.resultHandlers.setResultHandlers(Collections.singleton(resultHandler));
+		shell.resultHandler = resultHandler;
 		when(shell.lineReader.readLine(Mockito.<String>any())).thenThrow(
 			new UserInterruptException("some input"),
 			new UserInterruptException("")