Polishing

spring-context/src/main/java/org/springframework/scheduling/concurrent/DefaultManagedTaskScheduler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -35,10 +35,11 @@ import org.springframework.jndi.JndiTemplate;
  *
  * @author Juergen Hoeller
  * @since 4.0
+ * @see javax.enterprise.concurrent.ManagedScheduledExecutorService
  */
 public class DefaultManagedTaskScheduler extends ConcurrentTaskScheduler implements InitializingBean {
 
-	private JndiLocatorDelegate jndiLocator = new JndiLocatorDelegate();
+	private final JndiLocatorDelegate jndiLocator = new JndiLocatorDelegate();
 
 	private String jndiName = "java:comp/DefaultManagedScheduledExecutorService";
 

spring-core/src/main/java/org/springframework/util/MimeType.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -193,7 +193,7 @@ public class MimeType implements Comparable<MimeType>, Serializable {
 	 * @see <a href="https://tools.ietf.org/html/rfc2616#section-2.2">HTTP 1.1, section 2.2</a>
 	 */
 	private void checkToken(String token) {
-		for (int i = 0; i < token.length(); i++ ) {
+		for (int i = 0; i < token.length(); i++) {
 			char ch = token.charAt(i);
 			if (!TOKEN.get(ch)) {
 				throw new IllegalArgumentException("Invalid token character '" + ch + "' in token \"" + token + "\"");
@@ -206,8 +206,7 @@ public class MimeType implements Comparable<MimeType>, Serializable {
 		Assert.hasLength(value, "'value' must not be empty");
 		checkToken(attribute);
 		if (PARAM_CHARSET.equals(attribute)) {
-			value = unquote(value);
-			Charset.forName(value);
+			Charset.forName(unquote(value));
 		}
 		else if (!isQuotedString(value)) {
 			checkToken(value);

spring-messaging/src/main/java/org/springframework/messaging/converter/AbstractMessageConverter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -149,20 +149,6 @@ public abstract class AbstractMessageConverter implements SmartMessageConverter
 	}
 
 
-	/**
-	 * Returns the default content type for the payload. Called when
-	 * {@link #toMessage(Object, MessageHeaders)} is invoked without message headers or
-	 * without a content type header.
-	 * <p>By default, this returns the first element of the {@link #getSupportedMimeTypes()
-	 * supportedMimeTypes}, if any. Can be overridden in sub-classes.
-	 * @param payload the payload being converted to message
-	 * @return the content type, or {@code null} if not known
-	 */
-	protected MimeType getDefaultContentType(Object payload) {
-		List<MimeType> mimeTypes = getSupportedMimeTypes();
-		return (!mimeTypes.isEmpty() ? mimeTypes.get(0) : null);
-	}
-
 	@Override
 	public final Object fromMessage(Message<?> message, Class<?> targetClass) {
 		return fromMessage(message, targetClass, null);
@@ -176,10 +162,6 @@ public abstract class AbstractMessageConverter implements SmartMessageConverter
 		return convertFromInternal(message, targetClass, conversionHint);
 	}
 
-	protected boolean canConvertFrom(Message<?> message, Class<?> targetClass) {
-		return (supports(targetClass) && supportsMimeType(message.getHeaders()));
-	}
-
 	@Override
 	public final Message<?> toMessage(Object payload, MessageHeaders headers) {
 		return toMessage(payload, headers, null);
@@ -213,6 +195,11 @@ public abstract class AbstractMessageConverter implements SmartMessageConverter
 		return builder.build();
 	}
 
+
+	protected boolean canConvertFrom(Message<?> message, Class<?> targetClass) {
+		return (supports(targetClass) && supportsMimeType(message.getHeaders()));
+	}
+
 	protected boolean canConvertTo(Object payload, MessageHeaders headers) {
 		Class<?> clazz = (payload != null ? payload.getClass() : null);
 		return (supports(clazz) && supportsMimeType(headers));
@@ -238,6 +225,21 @@ public abstract class AbstractMessageConverter implements SmartMessageConverter
 		return (this.contentTypeResolver != null ? this.contentTypeResolver.resolve(headers) : null);
 	}
 
+	/**
+	 * Return the default content type for the payload. Called when
+	 * {@link #toMessage(Object, MessageHeaders)} is invoked without
+	 * message headers or without a content type header.
+	 * <p>By default, this returns the first element of the
+	 * {@link #getSupportedMimeTypes() supportedMimeTypes}, if any.
+	 * Can be overridden in subclasses.
+	 * @param payload the payload being converted to a message
+	 * @return the content type, or {@code null} if not known
+	 */
+	protected MimeType getDefaultContentType(Object payload) {
+		List<MimeType> mimeTypes = getSupportedMimeTypes();
+		return (!mimeTypes.isEmpty() ? mimeTypes.get(0) : null);
+	}
+
 
 	/**
 	 * Whether the given class is supported by this converter.

spring-messaging/src/main/java/org/springframework/messaging/simp/stomp/DefaultStompSession.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -654,8 +654,10 @@ public class DefaultStompSession implements ConnectionHandlingStompSession {
 			if (conn != null) {
 				conn.send(HEARTBEAT).addCallback(
 						new ListenableFutureCallback<Void>() {
+							@Override
 							public void onSuccess(Void result) {
 							}
+							@Override
 							public void onFailure(Throwable ex) {
 								handleFailure(ex);
 							}

spring-messaging/src/main/java/org/springframework/messaging/support/NativeMessageHeaderAccessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -52,14 +52,14 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 
 
 	/**
-	 * A protected constructor to create new headers.
+	 * Protected constructor to create a new instance.
 	 */
 	protected NativeMessageHeaderAccessor() {
 		this((Map<String, List<String>>) null);
 	}
 
 	/**
-	 * A protected constructor to create new headers.
+	 * Protected constructor to create an instance with the given native headers.
 	 * @param nativeHeaders native headers to create the message with (may be {@code null})
 	 */
 	protected NativeMessageHeaderAccessor(Map<String, List<String>> nativeHeaders) {
@@ -69,7 +69,7 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 	}
 
 	/**
-	 * A protected constructor accepting the headers of an existing message to copy.
+	 * Protected constructor that copies headers from another message.
 	 */
 	protected NativeMessageHeaderAccessor(Message<?> message) {
 		super(message);
@@ -84,13 +84,17 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 		}
 	}
 
+
+	/**
+	 * Subclasses can use this method to access the "native" headers sub-map.
+	 */
 	@SuppressWarnings("unchecked")
 	private Map<String, List<String>> getNativeHeaders() {
 		return (Map<String, List<String>>) getHeader(NATIVE_HEADERS);
 	}
 
 	/**
-	 * Return a copy of the native header values or an empty map.
+	 * Return a copy of the native headers sub-map, or an empty map.
 	 */
 	public Map<String, List<String>> toNativeHeaderMap() {
 		Map<String, List<String>> map = getNativeHeaders();
@@ -112,6 +116,7 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 
 	/**
 	 * Whether the native header map contains the give header name.
+	 * @param headerName the name of the header
 	 */
 	public boolean containsNativeHeader(String headerName) {
 		Map<String, List<String>> map = getNativeHeaders();
@@ -119,7 +124,9 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 	}
 
 	/**
-	 * @return all values for the specified native header or {@code null}.
+	 * Return all values for the specified native header, if present.
+	 * @param headerName the name of the header
+	 * @return the associated values, or {@code null} if none
 	 */
 	public List<String> getNativeHeader(String headerName) {
 		Map<String, List<String>> map = getNativeHeaders();
@@ -127,13 +134,15 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 	}
 
 	/**
-	 * @return the first value for the specified native header of {@code null}.
+	 * Return the first value for the specified native header, if present.
+	 * @param headerName the name of the header
+	 * @return the associated value, or {@code null} if none
 	 */
 	public String getFirstNativeHeader(String headerName) {
 		Map<String, List<String>> map = getNativeHeaders();
 		if (map != null) {
 			List<String> values = map.get(headerName);
-			if (values != null) {
+			if (!CollectionUtils.isEmpty(values)) {
 				return values.get(0);
 			}
 		}
@@ -142,6 +151,8 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 
 	/**
 	 * Set the specified native header value replacing existing values.
+	 * <p>In order for this to work, the accessor must be {@link #isMutable()
+	 * mutable}. See {@link MessageHeaderAccessor} for details.
 	 */
 	public void setNativeHeader(String name, String value) {
 		Assert.state(isMutable(), "Already immutable");
@@ -167,6 +178,10 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 
 	/**
 	 * Add the specified native header value to existing values.
+	 * <p>In order for this to work, the accessor must be {@link #isMutable()
+	 * mutable}. See {@link MessageHeaderAccessor} for details.
+	 * @param name the name of the header
+	 * @param value the header value to set
 	 */
 	public void addNativeHeader(String name, String value) {
 		Assert.state(isMutable(), "Already immutable");
@@ -187,6 +202,10 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 		setModified(true);
 	}
 
+	/**
+	 * Add the specified native headers to existing values.
+	 * @param headers the headers to set
+	 */
 	public void addNativeHeaders(MultiValueMap<String, String> headers) {
 		if (headers == null) {
 			return;
@@ -198,21 +217,36 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 		}
 	}
 
-	public List<String> removeNativeHeader(String name) {
+	/**
+	 * Remove the specified native header value replacing existing values.
+	 * <p>In order for this to work, the accessor must be {@link #isMutable()
+	 * mutable}. See {@link MessageHeaderAccessor} for details.
+	 * @param headerName the name of the header
+	 * @return the associated values, or {@code null} if the header was not present
+	 */
+	public List<String> removeNativeHeader(String headerName) {
 		Assert.state(isMutable(), "Already immutable");
 		Map<String, List<String>> nativeHeaders = getNativeHeaders();
-		if (nativeHeaders == null) {
+		if (CollectionUtils.isEmpty(nativeHeaders)) {
 			return null;
 		}
-		return nativeHeaders.remove(name);
+		return nativeHeaders.remove(headerName);
 	}
 
+
+	/**
+	 * Return the first value for the specified native header,
+	 * or {@code null} if none.
+	 * @param headerName the name of the header
+	 * @param headers the headers map to introspect
+	 * @return the associated value, or {@code null} if none
+	 */
 	@SuppressWarnings("unchecked")
 	public static String getFirstNativeHeader(String headerName, Map<String, Object> headers) {
 		Map<String, List<String>> map = (Map<String, List<String>>) headers.get(NATIVE_HEADERS);
 		if (map != null) {
 			List<String> values = map.get(headerName);
-			if (values != null) {
+			if (!CollectionUtils.isEmpty(values)) {
 				return values.get(0);
 			}
 		}

spring-messaging/src/test/java/org/springframework/messaging/converter/MappingJackson2MessageConverterTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -16,7 +16,6 @@
 
 package org.springframework.messaging.converter;
 
-import java.io.IOException;
 import java.lang.reflect.Method;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
@@ -74,7 +73,7 @@ public class MappingJackson2MessageConverterTests {
 	}
 
 	@Test
-	public void fromMessage() throws Exception {
+	public void fromMessage() {
 		MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
 		String payload = "{\"bytes\":\"AQI=\",\"array\":[\"Foo\",\"Bar\"],\"number\":42,\"string\":\"Foo\",\"bool\":true,\"fraction\":42.0}";
 		Message<?> message = MessageBuilder.withPayload(payload.getBytes(UTF_8)).build();
@@ -89,7 +88,7 @@ public class MappingJackson2MessageConverterTests {
 	}
 
 	@Test
-	public void fromMessageUntyped() throws Exception {
+	public void fromMessageUntyped() {
 		MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
 		String payload = "{\"bytes\":\"AQI=\",\"array\":[\"Foo\",\"Bar\"],"
 				+ "\"number\":42,\"string\":\"Foo\",\"bool\":true,\"fraction\":42.0}";
@@ -106,7 +105,7 @@ public class MappingJackson2MessageConverterTests {
 	}
 
 	@Test(expected = MessageConversionException.class)
-	public void fromMessageInvalidJson() throws Exception {
+	public void fromMessageInvalidJson() {
 		MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
 		String payload = "FooBar";
 		Message<?> message = MessageBuilder.withPayload(payload.getBytes(UTF_8)).build();
@@ -114,7 +113,7 @@ public class MappingJackson2MessageConverterTests {
 	}
 
 	@Test
-	public void fromMessageValidJsonWithUnknownProperty() throws IOException {
+	public void fromMessageValidJsonWithUnknownProperty() {
 		MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
 		String payload = "{\"string\":\"string\",\"unknownProperty\":\"value\"}";
 		Message<?> message = MessageBuilder.withPayload(payload.getBytes(UTF_8)).build();
@@ -151,7 +150,7 @@ public class MappingJackson2MessageConverterTests {
 	}
 
 	@Test
-	public void toMessage() throws Exception {
+	public void toMessage() {
 		MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
 		MyBean payload = new MyBean();
 		payload.setString("Foo");
@@ -239,11 +238,14 @@ public class MappingJackson2MessageConverterTests {
 		return bean;
 	}
 
-	public void jsonViewPayload(@JsonView(MyJacksonView2.class) JacksonViewBean payload) {}
+	public void jsonViewPayload(@JsonView(MyJacksonView2.class) JacksonViewBean payload) {
+	}
 
-	void handleList(List<Long> payload) {}
+	void handleList(List<Long> payload) {
+	}
 
-	void handleMessage(Message<MyBean> message) {}
+	void handleMessage(Message<MyBean> message) {
+	}
 
 
 	public static class MyBean {

spring-web/src/main/java/org/springframework/http/converter/HttpMessageConverter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -24,7 +24,7 @@ import org.springframework.http.HttpOutputMessage;
 import org.springframework.http.MediaType;
 
 /**
- * Strategy interface that specifies a converter that can convert from and to HTTP requests and responses.
+ * Strategy interface for converting from and to HTTP requests and responses.
  *
  * @author Arjen Poutsma
  * @author Juergen Hoeller
@@ -52,7 +52,7 @@ public interface HttpMessageConverter<T> {
 
 	/**
 	 * Return the list of {@link MediaType} objects supported by this converter.
-	 * @return the list of supported media types
+	 * @return the list of supported media types, potentially an immutable copy
 	 */
 	List<MediaType> getSupportedMediaTypes();
 

spring-web/src/main/java/org/springframework/web/util/UriComponentsBuilder.java

@@ -213,7 +213,7 @@ public class UriComponentsBuilder implements Cloneable {
 			}
 			builder.scheme(scheme);
 			if (opaque) {
-				String ssp = uri.substring(scheme.length()).substring(1);
+				String ssp = uri.substring(scheme.length() + 1);
 				if (StringUtils.hasLength(fragment)) {
 					ssp = ssp.substring(0, ssp.length() - (fragment.length() + 1));
 				}