Polished UriComponents implementation

(cherry picked from commit c3b624d)

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

@@ -177,11 +177,9 @@ final class HierarchicalUriComponents extends UriComponents {
 	@Override
 	public HierarchicalUriComponents encode(String encoding) throws UnsupportedEncodingException {
 		Assert.hasLength(encoding, "'encoding' must not be empty");
-
 		if (this.encoded) {
 			return this;
 		}
-
 		String encodedScheme = encodeUriComponent(this.getScheme(), encoding, Type.SCHEME);
 		String encodedUserInfo = encodeUriComponent(this.userInfo, encoding, Type.USER_INFO);
 		String encodedHost = encodeUriComponent(this.host, encoding, Type.HOST);
@@ -198,7 +196,6 @@ final class HierarchicalUriComponents extends UriComponents {
 			encodedQueryParams.put(encodedName, encodedValues);
 		}
 		String encodedFragment = encodeUriComponent(this.getFragment(), encoding, Type.FRAGMENT);
-
 		return new HierarchicalUriComponents(encodedScheme, encodedUserInfo, encodedHost, this.port, encodedPath,
 				encodedQueryParams, encodedFragment, true, false);
 	}
@@ -212,15 +209,11 @@ final class HierarchicalUriComponents extends UriComponents {
 	 * @return the encoded URI
 	 * @throws IllegalArgumentException when the given uri parameter is not a valid URI
 	 */
-	static String encodeUriComponent(String source, String encoding, Type type)
+	static String encodeUriComponent(String source, String encoding, Type type) throws UnsupportedEncodingException {
-			throws UnsupportedEncodingException {
-
 		if (source == null) {
 			return null;
 		}
-
 		Assert.hasLength(encoding, "'encoding' must not be empty");
-
 		byte[] bytes = encodeBytes(source.getBytes(encoding), type);
 		return new String(bytes, "US-ASCII");
 	}
@@ -229,8 +222,7 @@ final class HierarchicalUriComponents extends UriComponents {
 		Assert.notNull(source, "'source' must not be null");
 		Assert.notNull(type, "'type' must not be null");
 		ByteArrayOutputStream bos = new ByteArrayOutputStream(source.length);
-		for (int i = 0; i < source.length; i++) {
+		for (byte b : source) {
-			int b = source[i];
 			if (b < 0) {
 				b += 256;
 			}
@@ -277,9 +269,7 @@ final class HierarchicalUriComponents extends UriComponents {
 		if (source == null) {
 			return;
 		}
-
 		int length = source.length();
-
 		for (int i=0; i < length; i++) {
 			char ch = source.charAt(i);
 			if (ch == '%') {
@@ -309,8 +299,7 @@ final class HierarchicalUriComponents extends UriComponents {
 
 	@Override
 	protected HierarchicalUriComponents expandInternal(UriTemplateVariables uriVariables) {
-		Assert.state(!encoded, "Cannot expand an already encoded UriComponents object");
+		Assert.state(!this.encoded, "Cannot expand an already encoded UriComponents object");
-
 		String expandedScheme = expandUriComponent(this.getScheme(), uriVariables);
 		String expandedUserInfo = expandUriComponent(this.userInfo, uriVariables);
 		String expandedHost = expandUriComponent(this.host, uriVariables);
@@ -327,7 +316,6 @@ final class HierarchicalUriComponents extends UriComponents {
 			expandedQueryParams.put(expandedName, expandedValues);
 		}
 		String expandedFragment = expandUriComponent(this.getFragment(), uriVariables);
-
 		return new HierarchicalUriComponents(expandedScheme, expandedUserInfo, expandedHost, this.port, expandedPath,
 				expandedQueryParams, expandedFragment, false, false);
 	}
@@ -353,12 +341,10 @@ final class HierarchicalUriComponents extends UriComponents {
 	@Override
 	public String toUriString() {
 		StringBuilder uriBuilder = new StringBuilder();
-
 		if (getScheme() != null) {
 			uriBuilder.append(getScheme());
 			uriBuilder.append(':');
 		}
-
 		if (this.userInfo != null || this.host != null) {
 			uriBuilder.append("//");
 			if (this.userInfo != null) {
@@ -373,7 +359,6 @@ final class HierarchicalUriComponents extends UriComponents {
 				uriBuilder.append(port);
 			}
 		}
-
 		String path = getPath();
 		if (StringUtils.hasLength(path)) {
 			if (uriBuilder.length() != 0 && path.charAt(0) != PATH_DELIMITER) {
@@ -381,18 +366,15 @@ final class HierarchicalUriComponents extends UriComponents {
 			}
 			uriBuilder.append(path);
 		}
-
 		String query = getQuery();
 		if (query != null) {
 			uriBuilder.append('?');
 			uriBuilder.append(query);
 		}
-
 		if (getFragment() != null) {
 			uriBuilder.append('#');
 			uriBuilder.append(getFragment());
 		}
-
 		return uriBuilder.toString();
 	}
 
@@ -431,15 +413,13 @@ final class HierarchicalUriComponents extends UriComponents {
 			return false;
 		}
 		HierarchicalUriComponents other = (HierarchicalUriComponents) obj;
-		boolean rtn = true;
+		return ObjectUtils.nullSafeEquals(getScheme(), other.getScheme()) &&
-		rtn &= ObjectUtils.nullSafeEquals(getScheme(), other.getScheme());
+				ObjectUtils.nullSafeEquals(getUserInfo(), other.getUserInfo()) &&
-		rtn &= ObjectUtils.nullSafeEquals(getUserInfo(), other.getUserInfo());
+				ObjectUtils.nullSafeEquals(getHost(), other.getHost()) &&
-		rtn &= ObjectUtils.nullSafeEquals(getHost(), other.getHost());
+				getPort() == other.getPort() &&
-		rtn &= getPort() == other.getPort();
+				this.path.equals(other.path) &&
-		rtn &= this.path.equals(other.path);
+				this.queryParams.equals(other.queryParams) &&
-		rtn &= this.queryParams.equals(other.queryParams);
+				ObjectUtils.nullSafeEquals(getFragment(), other.getFragment());
-		rtn &= ObjectUtils.nullSafeEquals(getFragment(), other.getFragment());
-		return rtn;
 	}
 
 	@Override
@@ -532,15 +512,12 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		/**
 		 * Indicates whether the given character is allowed in this URI component.
-		 *
-		 * @param c the character
 		 * @return {@code true} if the character is allowed; {@code false} otherwise
 		 */
 		public abstract boolean isAllowed(int c);
 
 		/**
 		 * Indicates whether the given character is in the {@code ALPHA} set.
-		 *
 		 * @see <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986, appendix A</a>
 		 */
 		protected boolean isAlpha(int c) {
@@ -549,7 +526,6 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		/**
 		 * Indicates whether the given character is in the {@code DIGIT} set.
-		 *
 		 * @see <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986, appendix A</a>
 		 */
 		protected boolean isDigit(int c) {
@@ -558,7 +534,6 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		/**
 		 * Indicates whether the given character is in the {@code gen-delims} set.
-		 *
 		 * @see <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986, appendix A</a>
 		 */
 		protected boolean isGenericDelimiter(int c) {
@@ -567,7 +542,6 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		/**
 		 * Indicates whether the given character is in the {@code sub-delims} set.
-		 *
 		 * @see <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986, appendix A</a>
 		 */
 		protected boolean isSubDelimiter(int c) {
@@ -577,7 +551,6 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		/**
 		 * Indicates whether the given character is in the {@code reserved} set.
-		 *
 		 * @see <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986, appendix A</a>
 		 */
 		protected boolean isReserved(char c) {
@@ -586,7 +559,6 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		/**
 		 * Indicates whether the given character is in the {@code unreserved} set.
-		 *
 		 * @see <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986, appendix A</a>
 		 */
 		protected boolean isUnreserved(int c) {
@@ -595,7 +567,6 @@ final class HierarchicalUriComponents extends UriComponents {
 
 		/**
 		 * Indicates whether the given character is in the {@code pchar} set.
-		 *
 		 * @see <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986, appendix A</a>
 		 */
 		protected boolean isPchar(int c) {
@@ -624,11 +595,11 @@ final class HierarchicalUriComponents extends UriComponents {
 	/**
 	 * Represents a path backed by a string.
 	 */
-	final static class FullPathComponent implements PathComponent {
+	static final class FullPathComponent implements PathComponent {
 
 		private final String path;
 
-		FullPathComponent(String path) {
+		public FullPathComponent(String path) {
 			this.path = path;
 		}
 
@@ -668,14 +639,15 @@ final class HierarchicalUriComponents extends UriComponents {
 		}
 	}
 
+
 	/**
 	 * Represents a path backed by a string list (i.e. path segments).
 	 */
-	final static class PathSegmentComponent implements PathComponent {
+	static final class PathSegmentComponent implements PathComponent {
 
 		private final List<String> pathSegments;
 
-		PathSegmentComponent(List<String> pathSegments) {
+		public PathSegmentComponent(List<String> pathSegments) {
 			this.pathSegments = Collections.unmodifiableList(pathSegments);
 		}
 
@@ -732,17 +704,17 @@ final class HierarchicalUriComponents extends UriComponents {
 		public int hashCode() {
 			return getPathSegments().hashCode();
 		}
-
 	}
 
+
 	/**
 	 * Represents a collection of PathComponents.
 	 */
-	final static class PathComponentComposite implements PathComponent {
+	static final class PathComponentComposite implements PathComponent {
 
 		private final List<PathComponent> pathComponents;
 
-		PathComponentComposite(List<PathComponent> pathComponents) {
+		public PathComponentComposite(List<PathComponent> pathComponents) {
 			this.pathComponents = pathComponents;
 		}
 
@@ -763,15 +735,15 @@ final class HierarchicalUriComponents extends UriComponents {
 		}
 
 		public PathComponent encode(String encoding) throws UnsupportedEncodingException {
-			List<PathComponent> encodedComponents = new ArrayList<PathComponent>(pathComponents.size());
+			List<PathComponent> encodedComponents = new ArrayList<PathComponent>(this.pathComponents.size());
-			for (PathComponent pathComponent : pathComponents) {
+			for (PathComponent pathComponent : this.pathComponents) {
 				encodedComponents.add(pathComponent.encode(encoding));
 			}
 			return new PathComponentComposite(encodedComponents);
 		}
 
 		public void verify() {
-			for (PathComponent pathComponent : pathComponents) {
+			for (PathComponent pathComponent : this.pathComponents) {
 				pathComponent.verify();
 			}
 		}
@@ -786,41 +758,32 @@ final class HierarchicalUriComponents extends UriComponents {
 	}
 
 
-
 	/**
 	 * Represents an empty path.
 	 */
-	final static PathComponent NULL_PATH_COMPONENT = new PathComponent() {
+	static final PathComponent NULL_PATH_COMPONENT = new PathComponent() {
-
 		public String getPath() {
 			return null;
 		}
-
 		public List<String> getPathSegments() {
 			return Collections.emptyList();
 		}
-
 		public PathComponent encode(String encoding) throws UnsupportedEncodingException {
 			return this;
 		}
-
 		public void verify() {
 		}
-
 		public PathComponent expand(UriTemplateVariables uriVariables) {
 			return this;
 		}
-
 		@Override
 		public boolean equals(Object obj) {
 			return (this == obj);
 		}
-
 		@Override
 		public int hashCode() {
 			return 42;
 		}
-
 	};
 
 }

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

@@ -98,10 +98,14 @@ final class OpaqueUriComponents extends UriComponents {
 		String expandedScheme = expandUriComponent(this.getScheme(), uriVariables);
 		String expandedSSp = expandUriComponent(this.ssp, uriVariables);
 		String expandedFragment = expandUriComponent(this.getFragment(), uriVariables);
-
 		return new OpaqueUriComponents(expandedScheme, expandedSSp, expandedFragment);
 	}
 
+	@Override
+	public UriComponents normalize() {
+		return this;
+	}
+
 	@Override
 	public String toUriString() {
 		StringBuilder uriBuilder = new StringBuilder();
@@ -131,10 +135,6 @@ final class OpaqueUriComponents extends UriComponents {
 		}
 	}
 
-	@Override
-	public UriComponents normalize() {
-		return this;
-	}
 
 	@Override
 	public boolean equals(Object obj) {
@@ -146,11 +146,10 @@ final class OpaqueUriComponents extends UriComponents {
 		}
 
 		OpaqueUriComponents other = (OpaqueUriComponents) obj;
-		boolean rtn = true;
+		return ObjectUtils.nullSafeEquals(getScheme(), other.getScheme()) &&
-		rtn &= ObjectUtils.nullSafeEquals(getScheme(), other.getScheme());
+				ObjectUtils.nullSafeEquals(this.ssp, other.ssp) &&
-		rtn &= ObjectUtils.nullSafeEquals(this.ssp, other.ssp);
+				ObjectUtils.nullSafeEquals(getFragment(), other.getFragment());
-		rtn &= ObjectUtils.nullSafeEquals(getFragment(), other.getFragment());
+
-		return rtn;
 	}
 
 	@Override

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

@@ -64,7 +64,7 @@ public abstract class UriComponents implements Serializable {
 	 * Returns the scheme. Can be {@code null}.
 	 */
 	public final String getScheme() {
-		return scheme;
+		return this.scheme;
 	}
 
 	/**
@@ -115,11 +115,9 @@ public abstract class UriComponents implements Serializable {
 	}
 
 
-	// encoding
-
 	/**
-	 * Encode all URI components using their specific encoding rules, and returns the result
+	 * Encode all URI components using their specific encoding rules, and returns the
-	 * as a new {@code UriComponents} instance. This method uses UTF-8 to encode.
+	 * result as a new {@code UriComponents} instance. This method uses UTF-8 to encode.
 	 * @return the encoded uri components
 	 */
 	public final UriComponents encode() {
@@ -140,9 +138,6 @@ public abstract class UriComponents implements Serializable {
 	 */
 	public abstract UriComponents encode(String encoding) throws UnsupportedEncodingException;
 
-
-	// expanding
-
 	/**
 	 * Replaces all URI template variables with the values from a given map. The map keys
 	 * represent variable names; the values variable values. The order of variables is not
@@ -174,6 +169,30 @@ public abstract class UriComponents implements Serializable {
 	 */
 	abstract UriComponents expandInternal(UriTemplateVariables uriVariables);
 
+	/**
+	 * Normalize the path removing sequences like "path/..".
+	 * @see org.springframework.util.StringUtils#cleanPath(String)
+	 */
+	public abstract UriComponents normalize();
+
+	/**
+	 * Returns a URI string from this {@code UriComponents} instance.
+	 */
+	public abstract String toUriString();
+
+	/**
+	 * Returns a {@code URI} from this {@code UriComponents} instance.
+	 */
+	public abstract URI toUri();
+
+	@Override
+	public final String toString() {
+		return toUriString();
+	}
+
+
+	// static expansion helpers
+
 	static String expandUriComponent(String source, UriTemplateVariables uriVariables) {
 		if (source == null) {
 			return null;
@@ -197,34 +216,13 @@ public abstract class UriComponents implements Serializable {
 
 	private static String getVariableName(String match) {
 		int colonIdx = match.indexOf(':');
-		return colonIdx == -1 ? match : match.substring(0, colonIdx);
+		return (colonIdx != -1 ? match.substring(0, colonIdx) : match);
 	}
 
 	private static String getVariableValueAsString(Object variableValue) {
-		return variableValue != null ? variableValue.toString() : "";
+		return (variableValue != null ? variableValue.toString() : "");
 	}
 
-	/**
-	 * Returns a URI string from this {@code UriComponents} instance.
-	 */
-	public abstract String toUriString();
-
-	/**
-	 * Returns a {@code URI} from this {@code UriComponents} instance.
-	 */
-	public abstract URI toUri();
-
-	@Override
-	public final String toString() {
-		return toUriString();
-	}
-
-	/**
-	 * Normalize the path removing sequences like "path/..".
-	 * @see org.springframework.util.StringUtils#cleanPath(String)
-	 */
-	public abstract UriComponents normalize();
-
 
 	/**
 	 * Defines the contract for URI Template variables
@@ -233,9 +231,9 @@ public abstract class UriComponents implements Serializable {
 	interface UriTemplateVariables {
 
 		Object getValue(String name);
-
 	}
 
+
 	/**
 	 * URI template variables backed by a map.
 	 */
@@ -268,11 +266,11 @@ public abstract class UriComponents implements Serializable {
 		}
 
 		public Object getValue(String name) {
-			if (!valueIterator.hasNext()) {
+			if (!this.valueIterator.hasNext()) {
 				throw new IllegalArgumentException(
 						"Not enough variable values available to expand '" + name + "'");
 			}
-			return valueIterator.next();
+			return this.valueIterator.next();
 		}
 	}
 

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

@@ -100,9 +100,9 @@ public class UriComponentsBuilder {
 
 	private String fragment;
 
+
 	/**
 	 * Default constructor. Protected to prevent direct instantiation.
-	 *
 	 * @see #newInstance()
 	 * @see #fromPath(String)
 	 * @see #fromUri(URI)
@@ -110,11 +110,11 @@ public class UriComponentsBuilder {
 	protected UriComponentsBuilder() {
 	}
 
+
 	// Factory methods
 
 	/**
 	 * Returns a new, empty builder.
-	 *
 	 * @return the new {@code UriComponentsBuilder}
 	 */
 	public static UriComponentsBuilder newInstance() {
@@ -123,7 +123,6 @@ public class UriComponentsBuilder {
 
 	/**
 	 * Returns a builder that is initialized with the given path.
-	 *
 	 * @param path the path to initialize with
 	 * @return the new {@code UriComponentsBuilder}
 	 */
@@ -135,7 +134,6 @@ public class UriComponentsBuilder {
 
 	/**
 	 * Returns a builder that is initialized with the given {@code URI}.
-	 *
 	 * @param uri the URI to initialize with
 	 * @return the new {@code UriComponentsBuilder}
 	 */
@@ -147,20 +145,16 @@ public class UriComponentsBuilder {
 
 	/**
 	 * Returns a builder that is initialized with the given URI string.
-	 *
 	 * <p><strong>Note:</strong> The presence of reserved characters can prevent
 	 * correct parsing of the URI string. For example if a query parameter
 	 * contains {@code '='} or {@code '&'} characters, the query string cannot
 	 * be parsed unambiguously. Such values should be substituted for URI
 	 * variables to enable correct parsing:
-	 *
 	 * <pre>
 	 * String uriString = &quot;/hotels/42?filter={value}&quot;;
 	 * UriComponentsBuilder.fromUriString(uriString).buildAndExpand(&quot;hot&amp;cold&quot;);
 	 * </pre>
-	 *
+	 * @param uri the URI string to initialize with
-	 * @param uri
-	 *            the URI string to initialize with
 	 * @return the new {@code UriComponentsBuilder}
 	 */
 	public static UriComponentsBuilder fromUriString(String uri) {
@@ -168,7 +162,6 @@ public class UriComponentsBuilder {
 		Matcher m = URI_PATTERN.matcher(uri);
 		if (m.matches()) {
 			UriComponentsBuilder builder = new UriComponentsBuilder();
-
 			String scheme = m.group(2);
 			String userInfo = m.group(5);
 			String host = m.group(6);
@@ -176,19 +169,14 @@ public class UriComponentsBuilder {
 			String path = m.group(9);
 			String query = m.group(11);
 			String fragment = m.group(13);
-
 			boolean opaque = false;
-
 			if (StringUtils.hasLength(scheme)) {
 				String s = uri.substring(scheme.length());
 				if (!s.startsWith(":/")) {
 					opaque = true;
 				}
 			}
-
 			builder.scheme(scheme);
-
-
 			if (opaque) {
 				String ssp = uri.substring(scheme.length()).substring(1);
 				if (StringUtils.hasLength(fragment)) {
@@ -205,11 +193,9 @@ public class UriComponentsBuilder {
 				builder.path(path);
 				builder.query(query);
 			}
-
 			if (StringUtils.hasText(fragment)) {
 				builder.fragment(fragment);
 			}
-
 			return builder;
 		}
 		else {
@@ -219,18 +205,15 @@ public class UriComponentsBuilder {
 
 	/**
 	 * Creates a new {@code UriComponents} object from the string HTTP URL.
-	 *
 	 * <p><strong>Note:</strong> The presence of reserved characters can prevent
 	 * correct parsing of the URI string. For example if a query parameter
 	 * contains {@code '='} or {@code '&'} characters, the query string cannot
 	 * be parsed unambiguously. Such values should be substituted for URI
 	 * variables to enable correct parsing:
-	 *
 	 * <pre>
 	 * String uriString = &quot;/hotels/42?filter={value}&quot;;
 	 * UriComponentsBuilder.fromUriString(uriString).buildAndExpand(&quot;hot&amp;cold&quot;);
 	 * </pre>
-	 *
 	 * @param httpUrl the source URI
 	 * @return the URI components of the URI
 	 */
@@ -258,12 +241,10 @@ public class UriComponentsBuilder {
 	}
 
 
-
 	// build methods
 
 	/**
 	 * Builds a {@code UriComponents} instance from the various components contained in this builder.
-	 *
 	 * @return the URI components
 	 */
 	public UriComponents build() {
@@ -273,18 +254,17 @@ public class UriComponentsBuilder {
 	/**
 	 * Builds a {@code UriComponents} instance from the various components
 	 * contained in this builder.
-	 *
 	 * @param encoded whether all the components set in this builder are
 	 * 	encoded ({@code true}) or not ({@code false}).
 	 * @return the URI components
 	 */
 	public UriComponents build(boolean encoded) {
-		if (ssp != null) {
+		if (this.ssp != null) {
-			return new OpaqueUriComponents(scheme, ssp, fragment);
+			return new OpaqueUriComponents(this.scheme, this.ssp, this.fragment);
 		}
 		else {
-			return new HierarchicalUriComponents(
+			return new HierarchicalUriComponents(this.scheme, this.userInfo, this.host, this.port,
-					scheme, userInfo, host, port, pathBuilder.build(), queryParams, fragment, encoded, true);
+					this.pathBuilder.build(), this.queryParams, this.fragment, encoded, true);
 		}
 	}
 
@@ -292,7 +272,6 @@ public class UriComponentsBuilder {
 	 * Builds a {@code UriComponents} instance and replaces URI template variables
 	 * with the values from a map. This is a shortcut method, which combines
 	 * calls to {@link #build()} and then {@link UriComponents#expand(Map)}.
-	 *
 	 * @param uriVariables the map of URI variables
 	 * @return the URI components with expanded values
 	 */
@@ -304,7 +283,6 @@ public class UriComponentsBuilder {
 	 * Builds a {@code UriComponents} instance and replaces URI template variables
 	 * with the values from an array. This is a shortcut method, which combines
 	 * calls to {@link #build()} and then {@link UriComponents#expand(Object...)}.
-	 *
 	 * @param uriVariableValues URI variable values
 	 * @return the URI components with expanded values
 	 */
@@ -312,19 +290,17 @@ public class UriComponentsBuilder {
 		return build(false).expand(uriVariableValues);
 	}
 
+
 	// URI components methods
 
 	/**
 	 * Initializes all components of this URI builder with the components of the given URI.
-	 *
 	 * @param uri the URI
 	 * @return this UriComponentsBuilder
 	 */
 	public UriComponentsBuilder uri(URI uri) {
 		Assert.notNull(uri, "'uri' must not be null");
-
 		this.scheme = uri.getScheme();
-
 		if (uri.isOpaque()) {
 			this.ssp = uri.getRawSchemeSpecificPart();
 			resetHierarchicalComponents();
@@ -369,9 +345,7 @@ public class UriComponentsBuilder {
 	/**
 	 * Sets the URI scheme. The given scheme may contain URI template variables,
 	 * and may also be {@code null} to clear the scheme of this builder.
-	 *
+	 * @param scheme the URI scheme
-	 * @param scheme
-	 *            the URI scheme
 	 * @return this UriComponentsBuilder
 	 */
 	public UriComponentsBuilder scheme(String scheme) {
@@ -384,7 +358,6 @@ public class UriComponentsBuilder {
 	 * {@linkplain #userInfo(String) user-info}, {@linkplain #host(String) host},
 	 * {@linkplain #port(int) port}, {@linkplain #path(String) path}, and
 	 * {@link #query(String) query}.
-	 *
 	 * @param ssp the URI scheme-specific-part, may contain URI template parameters
 	 * @return this UriComponentsBuilder
 	 */
@@ -398,7 +371,6 @@ public class UriComponentsBuilder {
 	 * Sets the URI user info. The given user info may contain URI template
 	 * variables, and may also be {@code null} to clear the user info of this
 	 * builder.
-	 *
 	 * @param userInfo the URI user info
 	 * @return this UriComponentsBuilder
 	 */
@@ -411,7 +383,6 @@ public class UriComponentsBuilder {
 	/**
 	 * Sets the URI host. The given host may contain URI template variables, and
 	 * may also be {@code null} to clear the host of this builder.
-	 *
 	 * @param host the URI host
 	 * @return this UriComponentsBuilder
 	 */
@@ -423,7 +394,6 @@ public class UriComponentsBuilder {
 
 	/**
 	 * Sets the URI port. Passing {@code -1} will clear the port of this builder.
-	 *
 	 * @param port the URI port
 	 * @return this UriComponentsBuilder
 	 */
@@ -437,7 +407,6 @@ public class UriComponentsBuilder {
 	/**
 	 * Appends the given path to the existing path of this builder. The given
 	 * path may contain URI template variables.
-	 *
 	 * @param path the URI path
 	 * @return this UriComponentsBuilder
 	 */
@@ -449,7 +418,6 @@ public class UriComponentsBuilder {
 
 	/**
 	 * Sets the path of this builder overriding all existing path and path segment values.
-	 *
 	 * @param path the URI path; a {@code null} value results in an empty path.
 	 * @return this UriComponentsBuilder
 	 */
@@ -462,7 +430,6 @@ public class UriComponentsBuilder {
 	/**
 	 * Appends the given path segments to the existing path of this builder. Each given
 	 * path segments may contain URI template variables.
-	 *
 	 * @param pathSegments the URI path segments
 	 * @return this UriComponentsBuilder
 	 */
@@ -476,18 +443,15 @@ public class UriComponentsBuilder {
 	/**
 	 * Appends the given query to the existing query of this builder.
 	 * The given query may contain URI template variables.
-	 *
 	 * <p><strong>Note:</strong> The presence of reserved characters can prevent
 	 * correct parsing of the URI string. For example if a query parameter
 	 * contains {@code '='} or {@code '&'} characters, the query string cannot
 	 * be parsed unambiguously. Such values should be substituted for URI
 	 * variables to enable correct parsing:
-	 *
 	 * <pre>
 	 * String uriString = &quot;/hotels/42?filter={value}&quot;;
 	 * UriComponentsBuilder.fromUriString(uriString).buildAndExpand(&quot;hot&amp;cold&quot;);
 	 * </pre>
-	 *
 	 * @param query the query string
 	 * @return this UriComponentsBuilder
 	 */
@@ -511,7 +475,6 @@ public class UriComponentsBuilder {
 
 	/**
 	 * Sets the query of this builder overriding all existing query parameters.
-	 *
 	 * @param query the query string; a {@code null} value removes all query parameters.
 	 * @return this UriComponentsBuilder
 	 */
@@ -527,11 +490,8 @@ public class UriComponentsBuilder {
 	 * given name or any of the values may contain URI template variables. If no
 	 * values are given, the resulting URI will contain the query parameter name
 	 * only (i.e. {@code ?foo} instead of {@code ?foo=bar}.
-	 *
+	 * @param name the query parameter name
-	 * @param name
+	 * @param values the query parameter values
-	 *            the query parameter name
-	 * @param values
-	 *            the query parameter values
 	 * @return this UriComponentsBuilder
 	 */
 	public UriComponentsBuilder queryParam(String name, Object... values) {
@@ -553,11 +513,8 @@ public class UriComponentsBuilder {
 	 * Sets the query parameter values overriding all existing query values for
 	 * the same parameter. If no values are given, the query parameter is
 	 * removed.
-	 *
+	 * @param name the query parameter name
-	 * @param name
+	 * @param values the query parameter values
-	 *            the query parameter name
-	 * @param values
-	 *            the query parameter values
 	 * @return this UriComponentsBuilder
 	 */
 	public UriComponentsBuilder replaceQueryParam(String name, Object... values) {
@@ -574,9 +531,7 @@ public class UriComponentsBuilder {
 	 * Sets the URI fragment. The given fragment may contain URI template
 	 * variables, and may also be {@code null} to clear the fragment of this
 	 * builder.
-	 *
+	 * @param fragment the URI fragment
-	 * @param fragment
-	 *            the URI fragment
 	 * @return this UriComponentsBuilder
 	 */
 	public UriComponentsBuilder fragment(String fragment) {
@@ -592,12 +547,14 @@ public class UriComponentsBuilder {
 
 
 	private interface PathComponentBuilder {
+
 		PathComponent build();
 	}
 
+
 	private static class CompositePathComponentBuilder implements PathComponentBuilder {
 
-		private LinkedList<PathComponentBuilder> componentBuilders = new LinkedList<PathComponentBuilder>();
+		private final LinkedList<PathComponentBuilder> componentBuilders = new LinkedList<PathComponentBuilder>();
 
 		public CompositePathComponentBuilder() {
 		}
@@ -650,8 +607,8 @@ public class UriComponentsBuilder {
 		public PathComponent build() {
 			int size = this.componentBuilders.size();
 			List<PathComponent> components = new ArrayList<PathComponent>(size);
-			for (int i = 0; i < size; i++) {
+			for (PathComponentBuilder componentBuilder : this.componentBuilders) {
-				PathComponent pathComponent = this.componentBuilders.get(i).build();
+				PathComponent pathComponent = componentBuilder.build();
 				if (pathComponent != null) {
 					components.add(pathComponent);
 				}
@@ -666,9 +623,10 @@ public class UriComponentsBuilder {
 		}
 	}
 
+
 	private static class FullPathComponentBuilder implements PathComponentBuilder {
 
-		private StringBuilder path = new StringBuilder();
+		private final StringBuilder path = new StringBuilder();
 
 		public void append(String path) {
 			this.path.append(path);
@@ -690,9 +648,10 @@ public class UriComponentsBuilder {
 		}
 	}
 
+
 	private static class PathSegmentComponentBuilder implements PathComponentBuilder {
 
-		private List<String> pathSegments = new LinkedList<String>();
+		private final List<String> pathSegments = new LinkedList<String>();
 
 		public void append(String... pathSegments) {
 			for (String pathSegment : pathSegments) {
@@ -703,8 +662,8 @@ public class UriComponentsBuilder {
 		}
 
 		public PathComponent build() {
-			return this.pathSegments.isEmpty() ?
+			return (this.pathSegments.isEmpty() ? null :
-					null : new HierarchicalUriComponents.PathSegmentComponent(this.pathSegments);
+					new HierarchicalUriComponents.PathSegmentComponent(this.pathSegments));
 		}
 	}