Polishing

spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassBeanDefinitionReader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -186,7 +186,7 @@ class ConfigurationClassBeanDefinitionReader {
 		// Consider name and any aliases
 		AnnotationAttributes bean = AnnotationConfigUtils.attributesFor(metadata, Bean.class);
 		List<String> names = new ArrayList<String>(Arrays.asList(bean.getStringArray("name")));
-		String beanName = (names.size() > 0 ? names.remove(0) : methodName);
+		String beanName = (!names.isEmpty() ? names.remove(0) : methodName);
 
 		// Register aliases even when overridden
 		for (String alias : names) {
@@ -336,7 +336,7 @@ class ConfigurationClassBeanDefinitionReader {
 					}
 					readerInstanceCache.put(readerClass, reader);
 				}
-				catch (Exception ex) {
+				catch (Throwable ex) {
 					throw new IllegalStateException(
 							"Could not instantiate BeanDefinitionReader class [" + readerClass.getName() + "]");
 				}

spring-jdbc/src/main/java/org/springframework/jdbc/core/metadata/CallParameterMetaData.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -21,16 +21,23 @@ package org.springframework.jdbc.core.metadata;
  *
  * @author Thomas Risberg
  * @since 2.5
+ * @see GenericCallMetaDataProvider
  */
 public class CallParameterMetaData {
+
 	private String parameterName;
+
 	private int parameterType;
+
 	private int sqlType;
+
 	private String typeName;
+
 	private boolean nullable;
 
+
 	/**
-	 * Constructor taking all the properties
+	 * Constructor taking all the properties.
 	 */
 	public CallParameterMetaData(String columnName, int columnType, int sqlType, String typeName, boolean nullable) {
 		this.parameterName = columnName;
@@ -45,34 +52,35 @@ public class CallParameterMetaData {
 	 * Get the parameter name.
 	 */
 	public String getParameterName() {
-		return parameterName;
+		return this.parameterName;
 	}
 
 	/**
 	 * Get the parameter type.
 	 */
 	public int getParameterType() {
-		return parameterType;
+		return this.parameterType;
 	}
 
 	/**
 	 * Get the parameter SQL type.
 	 */
 	public int getSqlType() {
-		return sqlType;
+		return this.sqlType;
 	}
 
 	/**
 	 * Get the parameter type name.
 	 */
 	public String getTypeName() {
-		return typeName;
+		return this.typeName;
 	}
 
 	/**
 	 * Get whether the parameter is nullable.
 	 */
 	public boolean isNullable() {
-		return nullable;
+		return this.nullable;
 	}
+
 }

spring-jdbc/src/main/java/org/springframework/jdbc/core/metadata/TableParameterMetaData.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -21,6 +21,7 @@ package org.springframework.jdbc.core.metadata;
  *
  * @author Thomas Risberg
  * @since 2.5
+ * @see GenericTableMetaDataProvider
  */
 public class TableParameterMetaData {
 

spring-orm/src/main/java/org/springframework/orm/jpa/EntityManagerFactoryUtils.java

@@ -450,7 +450,8 @@ public abstract class EntityManagerFactoryUtils {
 
 	/**
 	 * Callback for resource cleanup at the end of a non-JPA transaction
-	 * (e.g. when participating in a JtaTransactionManager transaction).
+	 * (e.g. when participating in a JtaTransactionManager transaction),
+	 * fully synchronized with the ongoing transaction.
 	 * @see org.springframework.transaction.jta.JtaTransactionManager
 	 */
 	private static class TransactionalEntityManagerSynchronization
@@ -465,6 +466,7 @@ public abstract class EntityManagerFactoryUtils {
 
 		public TransactionalEntityManagerSynchronization(
 				EntityManagerHolder emHolder, EntityManagerFactory emf, Object txData, boolean newEm) {
+
 			super(emHolder, emf);
 			this.transactionData = txData;
 			this.jpaDialect = (emf instanceof EntityManagerFactoryInfo ?
@@ -512,7 +514,9 @@ public abstract class EntityManagerFactoryUtils {
 		}
 
 		@Override
-		protected void cleanupResource(EntityManagerHolder resourceHolder, EntityManagerFactory resourceKey, boolean committed) {
+		protected void cleanupResource(
+				EntityManagerHolder resourceHolder, EntityManagerFactory resourceKey, boolean committed) {
+
 			if (!committed) {
 				// Clear all pending inserts/updates/deletes in the EntityManager.
 				// Necessary for pre-bound EntityManagers, to avoid inconsistent state.

spring-test/src/test/java/org/springframework/test/context/testng/TrackingTestNGTestListener.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -30,8 +30,11 @@ import org.testng.ITestResult;
 public class TrackingTestNGTestListener implements ITestListener {
 
 	public int testStartCount = 0;
+
 	public int testSuccessCount = 0;
+
 	public int testFailureCount = 0;
+
 	public int failedConfigurationsCount = 0;
 
 
@@ -66,4 +69,5 @@ public class TrackingTestNGTestListener implements ITestListener {
 	public void onTestSuccess(ITestResult testResult) {
 		this.testSuccessCount++;
 	}
+
 }

spring-web/src/main/java/org/springframework/http/client/SimpleClientHttpRequestFactory.java

@@ -64,13 +64,15 @@ public class SimpleClientHttpRequestFactory implements ClientHttpRequestFactory,
 	}
 
 	/**
-	 * Indicates whether this request factory should buffer the {@linkplain ClientHttpRequest#getBody() request body}
+	 * Indicate whether this request factory should buffer the
-	 * internally.
+	 * {@linkplain ClientHttpRequest#getBody() request body} internally.
-	 * <p>Default is {@code true}. When sending large amounts of data via POST or PUT, it is recommended
+	 * <p>Default is {@code true}. When sending large amounts of data via POST or PUT,
-	 * to change this property to {@code false}, so as not to run out of memory. This will result in a
+	 * it is recommended to change this property to {@code false}, so as not to run
-	 * {@link ClientHttpRequest} that either streams directly to the underlying {@link HttpURLConnection}
+	 * out of memory. This will result in a {@link ClientHttpRequest} that either
-	 * (if the {@link org.springframework.http.HttpHeaders#getContentLength() Content-Length} is known in advance),
+	 * streams directly to the underlying {@link HttpURLConnection} (if the
-	 * or that will use "Chunked transfer encoding" (if the {@code Content-Length} is not known in advance).
+	 * {@link org.springframework.http.HttpHeaders#getContentLength() Content-Length}
+	 * is known in advance), or that will use "Chunked transfer encoding"
+	 * (if the {@code Content-Length} is not known in advance).
 	 * @see #setChunkSize(int)
 	 * @see HttpURLConnection#setFixedLengthStreamingMode(int)
 	 */
@@ -79,9 +81,11 @@ public class SimpleClientHttpRequestFactory implements ClientHttpRequestFactory,
 	}
 
 	/**
-	 * Sets the number of bytes to write in each chunk when not buffering request bodies locally.
+	 * Set the number of bytes to write in each chunk when not buffering request
-	 * <p>Note that this parameter is only used when {@link #setBufferRequestBody(boolean) bufferRequestBody} is set
+	 * bodies locally.
-	 * to {@code false}, and the {@link org.springframework.http.HttpHeaders#getContentLength() Content-Length}
+	 * <p>Note that this parameter is only used when
+	 * {@link #setBufferRequestBody(boolean) bufferRequestBody} is set to {@code false},
+	 * and the {@link org.springframework.http.HttpHeaders#getContentLength() Content-Length}
 	 * is not known in advance.
 	 * @see #setBufferRequestBody(boolean)
 	 */

spring-web/src/main/java/org/springframework/web/bind/WebDataBinder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.

spring-web/src/main/java/org/springframework/web/client/ResponseErrorHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -21,7 +21,8 @@ import java.io.IOException;
 import org.springframework.http.client.ClientHttpResponse;
 
 /**
- * Strategy interface used by the {@link RestTemplate} to determine whether a particular response has an error or not.
+ * Strategy interface used by the {@link RestTemplate} to determine
+ * whether a particular response has an error or not.
  *
  * @author Arjen Poutsma
  * @since 3.0
@@ -29,9 +30,9 @@ import org.springframework.http.client.ClientHttpResponse;
 public interface ResponseErrorHandler {
 
 	/**
-	 * Indicates whether the given response has any errors.
+	 * Indicate whether the given response has any errors.
-	 * Implementations will typically inspect the {@link ClientHttpResponse#getStatusCode() HttpStatus}
+	 * <p>Implementations will typically inspect the
-	 * of the response.
+	 * {@link ClientHttpResponse#getStatusCode() HttpStatus} of the response.
 	 * @param response the response to inspect
 	 * @return {@code true} if the response has an error; {@code false} otherwise
 	 * @throws IOException in case of I/O errors
@@ -39,10 +40,12 @@ public interface ResponseErrorHandler {
 	boolean hasError(ClientHttpResponse response) throws IOException;
 
 	/**
-	 * Handles the error in the given response.
+	 * Handle the error in the given response.
-	 * This method is only called when {@link #hasError(ClientHttpResponse)} has returned {@code true}.
+	 * <p>This method is only called when {@link #hasError(ClientHttpResponse)}
+	 * has returned {@code true}.
 	 * @param response the response with the error
 	 * @throws IOException in case of I/O errors
 	 */
 	void handleError(ClientHttpResponse response) throws IOException;
+
 }

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2008 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -45,90 +45,88 @@ class HtmlCharacterEntityDecoder {
 	public HtmlCharacterEntityDecoder(HtmlCharacterEntityReferences characterEntityReferences, String original) {
 		this.characterEntityReferences = characterEntityReferences;
 		this.originalMessage = original;
-		this.decodedMessage = new StringBuilder(originalMessage.length());
+		this.decodedMessage = new StringBuilder(original.length());
 	}
 
+
 	public String decode() {
-		while (currentPosition < originalMessage.length()) {
+		while (this.currentPosition < this.originalMessage.length()) {
-			findNextPotentialReference(currentPosition);
+			findNextPotentialReference(this.currentPosition);
 			copyCharactersTillPotentialReference();
 			processPossibleReference();
 		}
-		return decodedMessage.toString();
+		return this.decodedMessage.toString();
 	}
 
 	private void findNextPotentialReference(int startPosition) {
-		nextPotentialReferencePosition = Math.max(startPosition, nextSemicolonPosition - MAX_REFERENCE_SIZE);
+		this.nextPotentialReferencePosition = Math.max(startPosition, this.nextSemicolonPosition - MAX_REFERENCE_SIZE);
 
 		do {
-			nextPotentialReferencePosition =
+			this.nextPotentialReferencePosition =
-					originalMessage.indexOf('&', nextPotentialReferencePosition);
+					this.originalMessage.indexOf('&', this.nextPotentialReferencePosition);
 
-			if (nextSemicolonPosition != -1 &&
+			if (this.nextSemicolonPosition != -1 &&
-					nextSemicolonPosition < nextPotentialReferencePosition)
+					this.nextSemicolonPosition < this.nextPotentialReferencePosition)
-				nextSemicolonPosition = originalMessage.indexOf(';', nextPotentialReferencePosition + 1);
+				this.nextSemicolonPosition = this.originalMessage.indexOf(';', this.nextPotentialReferencePosition + 1);
 
-			boolean isPotentialReference =
+			boolean isPotentialReference = (this.nextPotentialReferencePosition != -1 &&
-					nextPotentialReferencePosition != -1
+					this.nextSemicolonPosition != -1 &&
-					&& nextSemicolonPosition != -1
+					this.nextPotentialReferencePosition - this.nextSemicolonPosition < MAX_REFERENCE_SIZE);
-					&& nextPotentialReferencePosition - nextSemicolonPosition < MAX_REFERENCE_SIZE;
 
 			if (isPotentialReference) {
 				break;
 			}
-			if (nextPotentialReferencePosition == -1) {
+			if (this.nextPotentialReferencePosition == -1) {
 				break;
 			}
-			if (nextSemicolonPosition == -1) {
+			if (this.nextSemicolonPosition == -1) {
-				nextPotentialReferencePosition = -1;
+				this.nextPotentialReferencePosition = -1;
 				break;
 			}
 
-			nextPotentialReferencePosition = nextPotentialReferencePosition + 1;
+			this.nextPotentialReferencePosition = this.nextPotentialReferencePosition + 1;
 		}
-		while (nextPotentialReferencePosition != -1);
+		while (this.nextPotentialReferencePosition != -1);
 	}
 
-
 	private void copyCharactersTillPotentialReference() {
-		if (nextPotentialReferencePosition != currentPosition) {
+		if (this.nextPotentialReferencePosition != this.currentPosition) {
-			int skipUntilIndex = nextPotentialReferencePosition != -1 ?
+			int skipUntilIndex = (this.nextPotentialReferencePosition != -1 ?
-					nextPotentialReferencePosition : originalMessage.length();
+					this.nextPotentialReferencePosition : this.originalMessage.length());
-			if (skipUntilIndex - currentPosition > 3) {
+			if (skipUntilIndex - this.currentPosition > 3) {
-				decodedMessage.append(originalMessage.substring(currentPosition, skipUntilIndex));
+				this.decodedMessage.append(this.originalMessage.substring(this.currentPosition, skipUntilIndex));
-				currentPosition = skipUntilIndex;
+				this.currentPosition = skipUntilIndex;
 			}
 			else {
-				while (currentPosition < skipUntilIndex)
+				while (this.currentPosition < skipUntilIndex)
-					decodedMessage.append(originalMessage.charAt(currentPosition++));
+					this.decodedMessage.append(this.originalMessage.charAt(this.currentPosition++));
 			}
 		}
 	}
 
 	private void processPossibleReference() {
-		if (nextPotentialReferencePosition != -1) {
+		if (this.nextPotentialReferencePosition != -1) {
-			boolean isNumberedReference = originalMessage.charAt(currentPosition + 1) == '#';
+			boolean isNumberedReference = (this.originalMessage.charAt(this.currentPosition + 1) == '#');
 			boolean wasProcessable = isNumberedReference ? processNumberedReference() : processNamedReference();
 			if (wasProcessable) {
-				currentPosition = nextSemicolonPosition + 1;
+				this.currentPosition = this.nextSemicolonPosition + 1;
 			}
 			else {
-				char currentChar = originalMessage.charAt(currentPosition);
+				char currentChar = this.originalMessage.charAt(this.currentPosition);
-				decodedMessage.append(currentChar);
+				this.decodedMessage.append(currentChar);
-				currentPosition++;
+				this.currentPosition++;
 			}
 		}
 	}
 
 	private boolean processNumberedReference() {
-		boolean isHexNumberedReference =
+		char referenceChar = this.originalMessage.charAt(this.nextPotentialReferencePosition + 2);
-				originalMessage.charAt(nextPotentialReferencePosition + 2) == 'x' ||
+		boolean isHexNumberedReference = (referenceChar == 'x' || referenceChar == 'X');
-				originalMessage.charAt(nextPotentialReferencePosition + 2) == 'X';
 		try {
-			int value = (!isHexNumberedReference) ?
+			int value = (!isHexNumberedReference ?
 					Integer.parseInt(getReferenceSubstring(2)) :
-					Integer.parseInt(getReferenceSubstring(3), 16);
+					Integer.parseInt(getReferenceSubstring(3), 16));
-			decodedMessage.append((char) value);
+			this.decodedMessage.append((char) value);
 			return true;
 		}
 		catch (NumberFormatException ex) {
@@ -138,16 +136,17 @@ class HtmlCharacterEntityDecoder {
 
 	private boolean processNamedReference() {
 		String referenceName = getReferenceSubstring(1);
-		char mappedCharacter = characterEntityReferences.convertToCharacter(referenceName);
+		char mappedCharacter = this.characterEntityReferences.convertToCharacter(referenceName);
 		if (mappedCharacter != HtmlCharacterEntityReferences.CHAR_NULL) {
-			decodedMessage.append(mappedCharacter);
+			this.decodedMessage.append(mappedCharacter);
 			return true;
 		}
 		return false;
 	}
 
 	private String getReferenceSubstring(int referenceOffset) {
-		return originalMessage.substring(nextPotentialReferencePosition + referenceOffset, nextSemicolonPosition);
+		return this.originalMessage.substring(
+				this.nextPotentialReferencePosition + referenceOffset, this.nextSemicolonPosition);
 	}
 
 }

spring-web/src/test/java/org/springframework/http/converter/json/GsonHttpMessageConverterTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -94,7 +94,7 @@ public class GsonHttpMessageConverterTests {
 		assertEquals(42, n.longValue());
 		n = (Number) result.get("fraction");
 		assertEquals(42D, n.doubleValue(), 0D);
-		List<String> array = new ArrayList<String>();
+		List<String> array = new ArrayList<>();
 		array.add("Foo");
 		array.add("Bar");
 		assertEquals(array, result.get("array"));
@@ -118,15 +118,14 @@ public class GsonHttpMessageConverterTests {
 		body.setBool(true);
 		body.setBytes(new byte[]{0x1, 0x2});
 		this.converter.write(body, null, outputMessage);
-		Charset utf8 = Charset.forName("UTF-8");
+		String result = outputMessage.getBodyAsString(UTF8);
-		String result = outputMessage.getBodyAsString(utf8);
 		assertTrue(result.contains("\"string\":\"Foo\""));
 		assertTrue(result.contains("\"number\":42"));
 		assertTrue(result.contains("fraction\":42.0"));
 		assertTrue(result.contains("\"array\":[\"Foo\",\"Bar\"]"));
 		assertTrue(result.contains("\"bool\":true"));
 		assertTrue(result.contains("\"bytes\":[1,2]"));
-		assertEquals("Invalid content-type", new MediaType("application", "json", utf8),
+		assertEquals("Invalid content-type", new MediaType("application", "json", UTF8),
 				outputMessage.getHeaders().getContentType());
 	}
 
@@ -166,8 +165,7 @@ public class GsonHttpMessageConverterTests {
 		};
 		String body = "[{\"bytes\":[1,2],\"array\":[\"Foo\",\"Bar\"]," +
 				"\"number\":42,\"string\":\"Foo\",\"bool\":true,\"fraction\":42.0}]";
-		MockHttpInputMessage inputMessage = new MockHttpInputMessage(
+		MockHttpInputMessage inputMessage = new MockHttpInputMessage(body.getBytes(UTF8));
-				body.getBytes(UTF8));
 		inputMessage.getHeaders().setContentType(new MediaType("application", "json"));
 
 		List<MyBean> results = (List<MyBean>) converter.read(List.class, inputMessage);
@@ -189,8 +187,7 @@ public class GsonHttpMessageConverterTests {
 
 		String body = "[{\"bytes\":[1,2],\"array\":[\"Foo\",\"Bar\"]," +
 				"\"number\":42,\"string\":\"Foo\",\"bool\":true,\"fraction\":42.0}]";
-		MockHttpInputMessage inputMessage = new MockHttpInputMessage(
+		MockHttpInputMessage inputMessage = new MockHttpInputMessage(body.getBytes(UTF8));
-				body.getBytes(UTF8));
 		inputMessage.getHeaders().setContentType(new MediaType("application", "json"));
 
 		GsonHttpMessageConverter converter = new GsonHttpMessageConverter();

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ExtendedServletRequestDataBinder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -54,6 +54,7 @@ public class ExtendedServletRequestDataBinder extends ServletRequestDataBinder {
 		super(target, objectName);
 	}
 
+
 	/**
 	 * Merge URI variables into the property values to use for data binding.
 	 */
@@ -65,8 +66,10 @@ public class ExtendedServletRequestDataBinder extends ServletRequestDataBinder {
 		if (uriVars != null) {
 			for (Entry<String, String> entry : uriVars.entrySet()) {
 				if (mpvs.contains(entry.getKey())) {
-					logger.warn("Skipping URI variable '" + entry.getKey()
+					if (logger.isWarnEnabled()) {
-							+ "' since the request contains a bind value with the same name.");
+						logger.warn("Skipping URI variable '" + entry.getKey() +
+								"' since the request contains a bind value with the same name.");
+					}
 				}
 				else {
 					mpvs.addPropertyValue(entry.getKey(), entry.getValue());

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ServletModelAttributeMethodProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -48,6 +48,7 @@ import org.springframework.web.servlet.HandlerMapping;
 public class ServletModelAttributeMethodProcessor extends ModelAttributeMethodProcessor {
 
 	/**
+	 * Class constructor.
 	 * @param annotationNotRequired if "true", non-simple method arguments and
 	 * return values are considered model attributes with or without a
 	 * {@code @ModelAttribute} annotation
@@ -87,20 +88,20 @@ public class ServletModelAttributeMethodProcessor extends ModelAttributeMethodPr
 	 * a URI variable first and then a request parameter.
 	 * @param attributeName the model attribute name
 	 * @param request the current request
-	 * @return the request value to try to convert or {@code null}
+	 * @return the request value to try to convert, or {@code null} if none
 	 */
 	protected String getRequestValueForAttribute(String attributeName, NativeWebRequest request) {
 		Map<String, String> variables = getUriTemplateVariables(request);
-		if (StringUtils.hasText(variables.get(attributeName))) {
+		String variableValue = variables.get(attributeName);
-			return variables.get(attributeName);
+		if (StringUtils.hasText(variableValue)) {
+			return variableValue;
 		}
-		else if (StringUtils.hasText(request.getParameter(attributeName))) {
+		String parameterValue = request.getParameter(attributeName);
-			return request.getParameter(attributeName);
+		if (StringUtils.hasText(parameterValue)) {
+			return parameterValue;
 		}
-		else {
 		return null;
 	}
-	}
 
 	@SuppressWarnings("unchecked")
 	protected final Map<String, String> getUriTemplateVariables(NativeWebRequest request) {
@@ -115,11 +116,12 @@ public class ServletModelAttributeMethodProcessor extends ModelAttributeMethodPr
 	 * <p>The default implementation converts only if there a registered
 	 * {@link Converter} that can perform the conversion.
 	 * @param sourceValue the source value to create the model attribute from
-	 * @param attributeName the name of the attribute, never {@code null}
+	 * @param attributeName the name of the attribute (never {@code null})
 	 * @param methodParam the method parameter
 	 * @param binderFactory for creating WebDataBinder instance
 	 * @param request the current request
-	 * @return the created model attribute, or {@code null}
+	 * @return the created model attribute, or {@code null} if no suitable
+	 * conversion found
 	 * @throws Exception
 	 */
 	protected Object createAttributeFromRequestValue(String sourceValue, String attributeName,