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Diffstat (limited to 'plugins/org.eclipse.wst.common.uriresolver/src/org/eclipse/wst/common/uriresolver/internal/URI.java')
| -rw-r--r-- | plugins/org.eclipse.wst.common.uriresolver/src/org/eclipse/wst/common/uriresolver/internal/URI.java | 2019 |
1 files changed, 0 insertions, 2019 deletions
diff --git a/plugins/org.eclipse.wst.common.uriresolver/src/org/eclipse/wst/common/uriresolver/internal/URI.java b/plugins/org.eclipse.wst.common.uriresolver/src/org/eclipse/wst/common/uriresolver/internal/URI.java deleted file mode 100644 index 3aac82348..000000000 --- a/plugins/org.eclipse.wst.common.uriresolver/src/org/eclipse/wst/common/uriresolver/internal/URI.java +++ /dev/null @@ -1,2019 +0,0 @@ -/* -* Copyright (c) 2002 IBM Corporation and others. -* All rights reserved. This program and the accompanying materials -* are made available under the terms of the Common Public License v1.0 -* which accompanies this distribution, and is available at -* http://www.eclipse.org/legal/cpl-v10.html -* -* Contributors: -* IBM - Initial API and implementation -* Jens Lukowski/Innoopract - initial renaming/restructuring -* -*/ -package org.eclipse.wst.common.uriresolver.internal; - -import java.io.File; - -import java.util.ArrayList; -import java.util.Arrays; -import java.util.Collections; -import java.util.List; - -/** - * A representation of a Uniform Resource Identifier (URI), as specified by - * <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, with certain - * enhancements. A <code>URI</code> instance can be created by specifying - * values for its components, or by providing a single URI string, which is - * parsed into its components. Static factory methods whose names begin - * with "create" are used for both forms of object creation. No public or - * protected constructors are provided; this class can not be subclassed. - * - * <p>Like <code>String</code>, <code>URI</code> is an immutable class; - * a <code>URI</code> instance offers several by-value methods that return a - * new <code>URI</code> object based on its current state. Most useful, - * a relative <code>URI</code> can be {@link #resolve(URI) resolve}d against - * a base absolute <code>URI</code> -- the latter typically identifies the - * document in which the former appears. The inverse to this is {@link - * #deresolve(URI) deresolve}, which answers the question, "what relative - * URI will resolve, against the given base, to this absolute URI?" - * - * <p>In the <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC</a>, much - * attention is focused on a hierarchical naming system used widely to - * locate resources via common protocols such as HTTP, FTP, and Gopher, and - * to identify files on a local file system. Acordingly, most of this - * class's functionality is for handling such URIs, which can be identified - * via {@link #isHierarchical()}. - * - * <p><a name="device_explaination"> - * The primary enhancement beyond the RFC description is an optional - * device component. Instead of treating the device as just another segment - * in the path, it can be stored as a separate component (almost a - * sub-authority), with the root below it. For example, resolving - * <code>/bar</code> against <code>file:///c:/foo</code> would result in - * <code>file:///c:/bar</code> being returned. Also, you cannot take - * the parent of a device, so resolving <code>..</code> against - * <code>file:///c:/</code> would not yield <code>file:///</code>, as you - * might expect. This feature is useful when working with file-scheme - * URIs, as devices do not typically occur in protocol-based ones. A - * device-enabled <code>URI</code> can be created by parsing a string with - * {@link #createURI} or by specifying a non-null <code>device</code> - * paramter for either the {@link #createHierarchicalURI(String, String, - * String, String, String) no-path} or the {@link - * #createHierarchicalURI(String, String, String, String[], String, String) - * absolute-path} form of <code>createHierarchicalURI()</code>. - * - * <p>Compared to the RFC description, this implementation is quite relaxed - * about validity. Static methods whose names begin with "valid" test - * whether a given string is a valid value for the various URI components. - * Presently, these tests place no restrictions beyond what would have been - * required in order for {@link #createURI} to - * have parsed them correctly from a single URI string. Note that all of - * the static factory methods invoke the appropriate validation methods and - * throw exceptions in response to a negative result, ensuring that - * invalid URIs are never created. - * - * <p>Finally, note the difference between a <code>null</code> parameter to - * the static factory methods and an empty string. The former signifies the - * absense of a given URI component, while the latter simply makes the - * component blank. This can have a significant effect when resolving. For - * example, consider the following two URIs: <code>/bar</code> (with no - * authority) and <code>///bar</code> (with a blank authority). Imagine - * resolving them against a base with an authority, such as - * <code>http://www.eclipse.org/</code>. The former case will yield - * <code>http://www.eclipse.org/bar</code>, as the base authority will be - * preserved. In the latter case, the empty authority will override the - * base authority, resulting in <code>http:///bar</code>! - */ -public final class URI -{ - // Common to all URI types. - private final int hashCode; - private final boolean hierarchical; - private final String scheme; // null -> relative URI reference - private final String authority; - private final String fragment; - private URI cachedTrimFragment; - private String cachedToString; - - // Applicable only to a hierarchical URI. - private final String device; - private final boolean absolutePath; - private final String[] segments; // empty last segment -> trailing separator - private final String query; - - // Identifies a file-type absolute URI. - private static final String SCHEME_FILE = "file"; - private static final String SCHEME_JAR = "jar"; - - // Special segment values interpreted at resolve and resolve time. - private static final String SEGMENT_EMPTY = ""; - private static final String SEGMENT_SELF = "."; - private static final String SEGMENT_PARENT = ".."; - private static final String[] NO_SEGMENTS = new String[0]; - - // Separators for parsing a URI string - private static final char SCHEME_SEPARATOR = ':'; - private static final String AUTHORITY_SEPARATOR = "//"; - private static final char DEVICE_IDENTIFIER = ':'; - private static final char SEGMENT_SEPARATOR = '/'; - private static final char QUERY_SEPARATOR = '?'; - private static final char FRAGMENT_SEPARATOR = '#'; - private static final char USER_INFO_SEPARATOR = '@'; - private static final char PORT_SEPARATOR = ':'; - private static final char FILE_EXTENSION_SEPARATOR = '.'; - private static final char[] MAJOR_SEPARATORS = { - SCHEME_SEPARATOR, SEGMENT_SEPARATOR, QUERY_SEPARATOR, FRAGMENT_SEPARATOR }; - private static final char[] SEGMENT_END = { - SEGMENT_SEPARATOR, QUERY_SEPARATOR, FRAGMENT_SEPARATOR }; - - /** - * Static factory method for a generic, non-hierarchical URI. There is no - * concept of a relative non-hierarchical URI; such an object cannot be - * created. - * - * @exception java.lang.IllegalArgumentException if <code>scheme</code> is - * null, or if <code>scheme</code>, <code>opaquePart</code>, or - * <code>fragment</code> is not valid according to {@link #validScheme}, - * {@link #validOpaquePart}, or {@link #validFragment}, respectively. - */ - public static URI createGenericURI(String scheme, String opaquePart, - String fragment) - { - if (scheme == null) - { - throw new IllegalArgumentException("relative non-hierarchical URI"); - } - - return new URI(false, scheme, opaquePart, null, false, NO_SEGMENTS, - null, fragment); - } - - /** - * Static factory method for a hierarchical URI with no path. The - * URI will be relative if <code>scheme</code> is non-null, and absolute - * otherwise. An absolute URI with no path requires a non-null - * <code>authority</code> and/or <code>device</code>. - * - * @exception java.lang.IllegalArgumentException if <code>scheme</code> is - * non-null while <code>authority</code> and <code>device</code> are null, - * or if <code>scheme</code>, <code>authority</code>, <code>device</code>, - * <code>query</code>, or <code>fragment</code> is not valid according to - * {@link #validScheme}, {@link #validAuthority}, {@link #validDevice}, - * {@link #validQuery}, or {@link #validFragment}, respectively. - */ - public static URI createHierarchicalURI(String scheme, String authority, - String device, String query, - String fragment) - { - if (scheme != null && authority == null && device == null) - { - throw new IllegalArgumentException( - "absolute hierarchical URI without authority, device, path"); - } - - return new URI(true, scheme, authority, device, false, NO_SEGMENTS, - query, fragment); - } - - /** - * Static factory method for a hierarchical URI with absolute path. - * The URI will be relative if <code>scheme</code> is non-null, and - * absolute otherwise. - * - * @param segments an array of non-null strings, each representing one - * segment of the path. As an absolute path, it is automatically - * preceeded by a <code>/</code> separator. If desired, a trailing - * separator should be represented by an empty-string segment as the last - * element of the array. - * - * @exception java.lang.IllegalArgumentException if <code>scheme</code>, - * <code>authority</code>, <code>device</code>, <code>segments</code>, - * <code>query</code>, or <code>fragment</code> is not valid according to - * {@link #validScheme}, {@link #validAuthority}, {@link #validDevice}, - * {@link #validSegments}, {@link #validQuery}, or {@link #validFragment}, - * respectively. - */ - public static URI createHierarchicalURI(String scheme, String authority, - String device, String[] segments, - String query, String fragment) - { - return new URI(true, scheme, authority, device, true, fix(segments), - query, fragment); - } - - /** - * Static factory method for a relative hierarchical URI with relative - * path. - * - * @param segments an array of non-null strings, each representing one - * segment of the path. A trailing separator is represented by an - * empty-string segment at the end of the array. - * - * @exception java.lang.IllegalArgumentException if <code>segments</code>, - * <code>query</code>, or <code>fragment</code> is not valid according to - * {@link #validSegments}, {@link #validQuery}, or {@link #validFragment}, - * respectively. - */ - public static URI createHierarchicalURI(String[] segments, String query, - String fragment) - { - return new URI(true, null, null, null, false, fix(segments), query, - fragment); - } - - // Converts null to length-zero array, and clones array to ensure - // immutability. - private static String[] fix(String[] segments) - { - return segments == null ? NO_SEGMENTS : (String[])segments.clone(); - } - - /** - * Static factory method based on parsing a URI string, with - * <a href="#device_explaination">explicit device support</a> enabled. - * The specified string is parsed as described in <a - * href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>, and an - * appropriate <code>URI</code> is created and returned. Note that - * validity testing is not as strict as in the RFC; essentially, only - * separator characters are considered. So, for example, non-Latin - * alphabet characters appearing in the scheme would not be considered an - * error. - * - * @exception java.lang.IllegalArgumentException if any component parsed - * from <code>uri</code> is not valid according to {@link #validScheme}, - * {@link #validOpaquePart}, {@link #validAuthority}, {@link - * #validDevice}, {@link #validSegments}, {@link #validQuery}, or {@link - * #validFragment}, as appropriate. - */ - public static URI createURI(String uri) - { - return parseIntoURI(uri); - } - - /** - * Static factory method based on parsing a URI string, with - * <a href="#device_explaination">explicit device support</a> enabled. - * Note that validity testing is not a strict as in the RFC; essentially, - * only separator characters are considered. So, for example, non-Latin - * alphabet characters appearing in the scheme would not be considered an - * error. - * @exception java.lang.IllegalArgumentException if any component parsed - * from <code>uri</code> is not valid according to {@link #validScheme}, - * {@link #validOpaquePart}, {@link #validAuthority}, {@link - * #validDevice}, {@link #validSegments}, {@link #validQuery}, or {@link - * #validFragment}, as appropriate. - * @deprecated - */ - public static URI createDeviceURI(String uri) - { - return parseIntoURI(uri); - } - - // String-parsing implementation. - private static URI parseIntoURI(String uri) - { - boolean hierarchical = true; - String scheme = null; - String authority = null; - String device = null; - boolean absolutePath = false; - String[] segments = NO_SEGMENTS; - String query = null; - String fragment = null; - - int i = 0; - int j = findSeparator(uri, i, MAJOR_SEPARATORS); - - if (j < uri.length() && uri.charAt(j) == SCHEME_SEPARATOR) - { - scheme = uri.substring(i, j); - i = j + 1; - } - - if (uri.startsWith(AUTHORITY_SEPARATOR, i)) - { - i += AUTHORITY_SEPARATOR.length(); - j = findSeparator(uri, i, SEGMENT_END); - authority = uri.substring(i, j); - i = j; - } - else if (scheme != null && - (i == uri.length() || - uri.charAt(i) != SEGMENT_SEPARATOR && - !(scheme.equalsIgnoreCase(SCHEME_FILE) || scheme.equalsIgnoreCase(SCHEME_JAR)))) - { - hierarchical = false; - j = findSeparator(uri, i, new char[] { FRAGMENT_SEPARATOR }); - authority = uri.substring(i, j); - i = j; - } - - if (i < uri.length() && - uri.charAt(i) == SEGMENT_SEPARATOR) - { - j = findSeparator(uri, i + 1, SEGMENT_END); - String s = uri.substring(i + 1, j); - - if (s.length() > 0 && s.charAt(s.length() - 1) == DEVICE_IDENTIFIER) - { - device = s; - i = j; - } - } - - if (i < uri.length() && uri.charAt(i) == SEGMENT_SEPARATOR) - { - i++; - absolutePath = true; - } - - if (segmentsRemain(uri, i)) - { - List segmentList = new ArrayList(); - - while (segmentsRemain(uri, i)) - { - j = findSeparator(uri, i, SEGMENT_END); - segmentList.add(uri.substring(i, j)); - i = j; - - if (i < uri.length() && uri.charAt(i) == SEGMENT_SEPARATOR) - { - if (!segmentsRemain(uri, ++i)) segmentList.add(SEGMENT_EMPTY); - } - } - segments = new String[segmentList.size()]; - segmentList.toArray(segments); - } - - if (i < uri.length() && uri.charAt(i) == QUERY_SEPARATOR) - { - j = findSeparator(uri, ++i, new char[] { FRAGMENT_SEPARATOR }); - query = uri.substring(i, j); - i = j; - } - - if (i < uri.length()) // && uri.charAt(i) == FRAGMENT_SEPARATOR (implied) - { - fragment = uri.substring(++i); - } - - return new URI(hierarchical, scheme, authority, device, absolutePath, - segments, query, fragment); - } - - /** - * Static factory method based on parsing File path string, with - * <a href="#device_explaination">explicit device support</a> enabled. - * Note that validity testing is not a strict as in the RFC; essentially, - * only separator characters are considered. So, for example, non-Latin - * alphabet characters appearing in a path segment would not be considered an - * error. - * @exception java.lang.IllegalArgumentException if any component parsed - * from <code>uri</code> is not valid according to {@link #validScheme}, - * {@link #validOpaquePart}, {@link #validAuthority}, {@link - * #validDevice}, {@link #validSegments}, {@link #validQuery}, or {@link - * #validFragment}, as appropriate. - */ - public static URI createFileURI(String pathName) - { - File file = new File(pathName); - String uri = File.separatorChar != '/' ? pathName.replace(File.separatorChar, SEGMENT_SEPARATOR) : pathName; - if (file.isAbsolute()) - { - URI result = parseIntoURI((uri.charAt(0) == SEGMENT_SEPARATOR ? "file:" : "file:/") + uri); - return result; - } - else - { - URI result = parseIntoURI(uri); - if (result.scheme() != null) - { - throw new IllegalArgumentException("invalid relative pathName: " + pathName); - } - return result; - } - } - - /** - * Static factory method based on parsing a platform-relative path string. - * The <code>pathName</code> must be of the form - *<pre> - * /project-name/path - *</pre> - * and the result will be of the form - *<pre> - * platform:/resource/project-name/path - *</pre> - * The leading separator of the path will be provided if not present. - * This scheme supports relocatable projects in Eclipse and in stand-alone EMF. - * @exception java.lang.IllegalArgumentException if any component parsed - * from <code>uri</code> is not valid according to {@link #validScheme}, - * {@link #validOpaquePart}, {@link #validAuthority}, {@link - * #validDevice}, {@link #validSegments}, {@link #validQuery}, or {@link - * #validFragment}, as appropriate. - * @see org.eclipse.core.runtime.Platform#resolve - */ - public static URI createPlatformResourceURI(String pathName) - { - URI result = parseIntoURI((pathName.charAt(0) == SEGMENT_SEPARATOR ? "platform:/resource" : "platform:/resource/") + pathName); - return result; - } - - // Checks whether the string contains any more segments after the one that - // starts at position i. - private static boolean segmentsRemain(String uri, int i) - { - return i < uri.length() && uri.charAt(i) != QUERY_SEPARATOR && - uri.charAt(i) != FRAGMENT_SEPARATOR; - } - - // Finds the next occurance of one of the characters specified in - // separators in the given URI, beginning at index i. The index of the - // first separator, or uri.length() if there is no such character, is - // returned. Before searching, i is limited to be in the range - // [0, uri.length()]. - private static int findSeparator(String uri, int i, char[] separators) - { - int len = uri.length(); - if (i >= len) return len; - - outerLoop: for (i = i > 0 ? i : 0; i < len; i++) - { - for (int j = 0, slen = separators.length; j < slen; j++) - { - if (uri.charAt(i) == separators[j]) break outerLoop; - } - } - return i; - } - - // Private constructor for use of static factory methods. Does validation - // of each component, but assumes that the inter-component requirements - // described in the factory doc-comments are all satisfied. - private URI(boolean hierarchical, String scheme, String authority, - String device, boolean absolutePath, String[] segments, - String query, String fragment) - { - String name = null; - String value = null; - - if (!validScheme(scheme)) - { - throw new IllegalArgumentException("invalid scheme: " + scheme); - } - if (!hierarchical && !validOpaquePart(authority)) - { - throw new IllegalArgumentException("invalid opaquePart: " + authority); - } - if (hierarchical && !validAuthority(authority)) - { - throw new IllegalArgumentException("invalid authority: " + authority); - } - if (!validDevice(device)) - { - throw new IllegalArgumentException("invalid device: " + device); - } - if (!validSegments(segments)) - { - String s = segments == null ? "invalid segments: " + segments : - "invalid segment: " + firstInvalidSegment(segments); - throw new IllegalArgumentException(s); - } - if (!validQuery(query)) - { - throw new IllegalArgumentException("invalid query: " + query); - } - if (!validFragment(fragment)) - { - throw new IllegalArgumentException("invalid fragment: " + fragment); - } - - int hashCode = 0; - if (hierarchical) - { - ++hashCode; - } - if (absolutePath) - { - hashCode += 2; - } - if (scheme != null) - { - hashCode ^= scheme.hashCode(); - } - if (authority != null) - { - hashCode ^= authority.hashCode(); - } - if (device != null) - { - hashCode ^= device.hashCode(); - } - if (query != null) - { - hashCode ^= query.hashCode(); - } - if (fragment != null) - { - hashCode ^= fragment.hashCode(); - } - - for (int i = 0, len = segments.length; i < len; i++) - { - hashCode ^= segments[i].hashCode(); - } - - this.hashCode = hashCode; - this.hierarchical = hierarchical; - this.scheme = scheme; - this.authority = authority; - this.device = device; - this.absolutePath = absolutePath; - this.segments = segments; - this.query = query; - this.fragment = fragment; - } - - // Searches the specified string for any of the specified target - // characters, and if any occur, returns true; false otherwise. - private static boolean contains(String s, char[] targets) - { - for (int i = 0, len = s.length(); i < len; i++) - { - for (int j = 0, tlen = targets.length; j < tlen; j++) - { - if (s.charAt(i) == targets[j]) return true; - } - } - return false; - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * valid as the scheme component of a URI; <code>false</code> otherwise. - * - * <p>A valid scheme may be null or contain any characters except for the - * following: <code>: / ? #</code> - */ - public static boolean validScheme(String value) - { - return value == null || !contains(value, MAJOR_SEPARATORS); - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * valid as the opaque part component of a URI; <code>false</code> - * otherwise. - * - * <p>A valid opaque part must be non-null, non-empty, and not contain the - * <code>#</code> character. In addition, its first character must not be - * <code>/</code> - */ - public static boolean validOpaquePart(String value) - { - return value != null && value.indexOf(FRAGMENT_SEPARATOR) == -1 && - value.length() > 0 && value.charAt(0) != SEGMENT_SEPARATOR; - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * valid as the authority component of a URI; <code>false</code> otherwise. - * - * <p>A valid authority may be null or contain any characters except for - * the following: <code>/ ? #</code> - */ - public static boolean validAuthority(String value) - { - return value == null || !contains(value, SEGMENT_END); - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * valid as the device component of a URI; <code>false</code> otherwise. - * - * <p>A valid device may be null or non-empty, containing any characters - * except for the following: <code>/ ? #</code> In addition, its last - * character must be <code>:</code> - */ - public static boolean validDevice(String value) - { - if (value == null) return true; - int len = value.length(); - return len > 0 && value.charAt(len - 1) == DEVICE_IDENTIFIER && - !contains(value, SEGMENT_END); - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * a valid path segment of a URI; <code>false</code> otherwise. - * - * <p>A valid path segment must be non-null and not contain any of the - * following characters: <code>/ ? #</code> - */ - public static boolean validSegment(String value) - { - return value != null && !contains(value, SEGMENT_END); - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * a valid path segment array of a URI; <code>false</code> otherwise. - * - * <p>A valid path segment array must be non-null and contain only path - * segements that are valid, according to {@link #validSegment}. - */ - public static boolean validSegments(String[] value) - { - if (value == null) return false; - for (int i = 0, len = value.length; i < len; i++) - { - if (!validSegment(value[i])) return false; - } - return true; - } - - // Returns null if the specicied value is null or would be a valid path - // segment array of a URI; otherwise, the value of the first invalid - // segment. - private static String firstInvalidSegment(String[] value) - { - if (value == null) return null; - for (int i = 0, len = value.length; i < len; i++) - { - if (!validSegment(value[i])) return value[i]; - } - return null; - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * valid as the query component of a URI; <code>false</code> otherwise. - * - * <p>A valid query may be null or contain any characters except for - * <code>#</code> - */ - public static boolean validQuery(String value) - { - return value == null || value.indexOf(FRAGMENT_SEPARATOR) == -1; - } - - /** - * Returns <code>true</code> if the specified <code>value</code> would be - * valid as the fragment component of a URI; <code>false</code> otherwise. - * - * <p>A fragment is taken to be unconditionally valid. - */ - public static boolean validFragment(String value) - { - return true; - } - - /** - * Returns <code>true</code> if this is a relative URI, or - * <code>false</code> if it is an absolute URI. - */ - public boolean isRelative() - { - return scheme == null; - } - - /** - * Returns <code>true</code> if this a a hierarchical URI, or - * <code>false</code> if it is of the generic form. - */ - public boolean isHierarchical() - { - return hierarchical; - } - - /** - * Returns <code>true</code> if this is a hierarcical URI with an authority - * component; <code>false</code> otherwise. - */ - public boolean hasAuthority() - { - return hierarchical && authority != null; - } - - /** - * Returns <code>true</code> if this is a non-hierarchical URI with an - * opaque part component; <code>false</code> otherwise. - */ - public boolean hasOpaquePart() - { - // note: hierarchical -> authority != null - return !hierarchical; - } - - /** - * Returns <code>true</code> if this is a hierarchical URI with a device - * component; <code>false</code> otherwise. - */ - public boolean hasDevice() - { - // note: device != null -> hierarchical - return device != null; - } - - /** - * Returns <code>true</code> if this is a hierarchical URI with an - * absolute or relative path; <code>false</code> otherwise. - */ - public boolean hasPath() - { - // note: (absolutePath || authority == null) -> hierarchical - // (authority == null && device == null && !absolutePath) -> scheme == null - return absolutePath || (authority == null && device == null); - } - - /** - * Returns <code>true</code> if this is a hierarchical URI with an - * absolute path, or <code>false</code> if it is non-hierarchical, has no - * path, or has a relative path. - */ - public boolean hasAbsolutePath() - { - // note: absolutePath -> hierarchical - return absolutePath; - } - - /** - * Returns <code>true</code> if this is a hierarchical URI with a relative - * path, or <code>false</code> if it is non-hierarchical, has no path, or - * has an absolute path. - */ - public boolean hasRelativePath() - { - // note: authority == null -> hierarchical - // (authority == null && device == null && !absolutePath) -> scheme == null - return authority == null && device == null && !absolutePath; - } - - /** - * Returns <code>true</code> if this is a hierarchical URI with an empty - * relative path; <code>false</code> otherwise. - * - * <p>Note that <code>!hasEmpty()</code> does <em>not</em> imply that this - * URI has any path segments; however, <code>hasRelativePath && - * !hasEmptyPath()</code> does. - */ - public boolean hasEmptyPath() - { - // note: authority == null -> hierarchical - // (authority == null && device == null && !absolutePath) -> scheme == null - return authority == null && device == null && !absolutePath && - segments.length == 0; - } - - /** - * Returns <code>true</code> if this is a hierarchical URI with a query - * component; <code>false</code> otherwise. - */ - public boolean hasQuery() - { - // note: query != null -> hierarchical - return query != null; - } - - /** - * Returns <code>true</code> if this URI has a fragment component; - * <code>false</code> otherwise. - */ - public boolean hasFragment() - { - return fragment != null; - } - - /** - * Returns <code>true</code> if this is a current document reference; that - * is, if it is a relative hierarchical URI with no authority, device or - * query components, and no path segments; <code>false</code> is returned - * otherwise. - */ - public boolean isCurrentDocumentReference() - { - // note: authority == null -> hierarchical - // (authority == null && device == null && !absolutePath) -> scheme == null - return authority == null && device == null && !absolutePath && - segments.length == 0 && query == null; - } - - /** - * Returns <code>true</code> if this is a {@link - * #isCurrentDocumentReference() current document reference} with no - * fragment component; <code>false</code> otherwise. - * - * @see #isCurrentDocumentReference() - */ - public boolean isEmpty() - { - // note: authority == null -> hierarchical - // (authority == null && device == null && !absolutePath) -> scheme == null - return authority == null && device == null && !absolutePath && - segments.length == 0 && query == null && fragment == null; - } - - /** - * Returns <code>true</code> if this is a hierarchical URI that may refer - * directly to a locally accessible file. This is considered to be the - * case for a file-scheme absolute URI, or for a relative URI with no query; - * <code>false</code> is returned otherwise. - */ - public boolean isFile() - { - return isHierarchical() && - ((isRelative() && !hasQuery()) || SCHEME_FILE.equalsIgnoreCase(scheme)); - } - - /** - * Returns the hash code. - */ - public int hashCode() - { - return hashCode; - } - - /** - * Returns <code>true</code> if <code>obj</code> is an instance of - * <code>URI</code> equal to this one; <code>false</code> otherwise. - * - * <p>Equality is determined strictly by comparing components, not by - * attempting to interpret what resource is being identified. - */ - public boolean equals(Object obj) - { - if (this == obj) return true; - if (!(obj instanceof URI)) return false; - URI uri = (URI) obj; - - return hashCode == uri.hashCode() && - hierarchical == uri.isHierarchical() && - absolutePath == uri.hasAbsolutePath() && - equals(scheme, uri.scheme()) && - equals(authority, hierarchical ? uri.authority() : uri.opaquePart()) && - equals(device, uri.device()) && - equals(query, uri.query()) && - equals(fragment, uri.fragment()) && - segmentsEqual(uri); - } - - // Tests whether this URI's path segment array is equal to that of the - // given uri. - private boolean segmentsEqual(URI uri) - { - if (segments.length != uri.segmentCount()) return false; - for (int i = 0, len = segments.length; i < len; i++) - { - if (!segments[i].equals(uri.segment(i))) return false; - } - return true; - } - - // Tests two objects for equality, tolerating nulls; null is considered - // to be a valid value that is only equal to itself. - private static boolean equals(Object o1, Object o2) - { - return o1 == null ? o2 == null : o1.equals(o2); - } - - /** - * If this is an absolute URI, returns the scheme component; - * <code>null</code> otherwise. - */ - public String scheme() - { - return scheme; - } - - /** - * If this is a non-hierarchical URI, returns the opaque part component; - * <code>null</code> otherwise. - */ - public String opaquePart() - { - return isHierarchical() ? null : authority; - } - - /** - * If this is a hierarchical URI with an authority component, returns it; - * <code>null</code> otherwise. - */ - public String authority() - { - return isHierarchical() ? authority : null; - } - - /** - * If this is a hierarchical URI with an authority component that has a - * user info portion, returns it; <code>null</code> otherwise. - */ - public String userInfo() - { - if (!hasAuthority()) return null; - - int i = authority.indexOf(USER_INFO_SEPARATOR); - return i < 0 ? null : authority.substring(0, i); - } - - /** - * If this is a hierarchical URI with an authority component that has a - * host portion, returns it; <code>null</code> otherwise. - */ - public String host() - { - if (!hasAuthority()) return null; - - int i = authority.indexOf(USER_INFO_SEPARATOR); - int j = authority.indexOf(PORT_SEPARATOR); - return j < 0 ? authority.substring(i + 1) : authority.substring(i + 1, j); - } - - /** - * If this is a hierarchical URI with an authority component that has a - * port portion, returns it; <code>null</code> otherwise. - */ - public String port() - { - if (!hasAuthority()) return null; - - int i = authority.indexOf(PORT_SEPARATOR); - return i < 0 ? null : authority.substring(i + 1); - } - - /** - * If this is a hierarchical URI with a device component, returns it; - * <code>null</code> otherwise. - */ - public String device() - { - return device; - } - - /** - * If this is a hierarchical URI with a path, returns an array containing - * the segments of the path; an empty array otherwise. The leading - * separator in an absolute path is not represented in this array, but a - * trailing separator is represented by an empty-string segment as the - * final element. - */ - public String[] segments() - { - return (String[])segments.clone(); - } - - /** - * Returns an unmodifiable list containing the same segments as the array - * returned by {@link #segments()}. - */ - public List segmentsList() - { - return Collections.unmodifiableList(Arrays.asList(segments)); - } - - /** - * Returns the number of elements in the segment array that would be - * returned by {@link #segments()}. - */ - public int segmentCount() - { - return segments.length; - } - - /** - * Provides fast, indexed access to individual segments in the path - * segment array. - * - * @exception java.lang.IndexOutOfBoundsException if <code>i < 0</code> or - * <code>i >= segmentCount()</code>. - */ - public String segment(int i) - { - return segments[i]; - } - - /** - * Returns the last segment in the segment array, or <code>null</code>. - */ - public String lastSegment() - { - int len = segments.length; - if (len == 0) return null; - return segments[len - 1]; - } - - /** - * If this is a hierarchical URI with a path, returns a string - * representation of the path; <code>null</code> otherwise. The path - * consists of a leading segment separator character (a slash), if the - * path is absolute, followed by the slash-separated path segments. If - * this URI has a separate <a href="#device_explaination">device - * component</a>, it is <em>not</em> included in the path. If it has a - * device stored as a path segment, it is included. - */ - public String path() - { - if (!hasPath()) return null; - - StringBuffer result = new StringBuffer(); - if (hasAbsolutePath()) result.append(SEGMENT_SEPARATOR); - - for (int i = 0, len = segments.length; i < len; i++) - { - if (i != 0) result.append(SEGMENT_SEPARATOR); - result.append(segments[i]); - } - return result.toString(); - } - - /** - * If this is a hierarchical URI with a path, returns a string - * representation of the path, including the authority and the - * <a href="#device_explaination">device component</a>; - * <code>null</code> otherwise. - * <p>The format of this string is - * <pre> - * //authority/device/pathSegment1/pathSegment2... - *</pre> - */ - public String devicePath() - { - if (!hasPath()) return null; - - StringBuffer result = new StringBuffer(); - if (hasAuthority()) - { - result.append(SEGMENT_SEPARATOR); - result.append(SEGMENT_SEPARATOR); - result.append(authority); - - if (hasDevice()) result.append(SEGMENT_SEPARATOR); - } - - if (hasDevice()) result.append(device); - if (hasAbsolutePath()) result.append(SEGMENT_SEPARATOR); - - for (int i = 0, len = segments.length; i < len; i++) - { - if (i != 0) result.append(SEGMENT_SEPARATOR); - result.append(segments[i]); - } - return result.toString(); - } - - /** - * If this is a hierarchical URI with a query component, returns it; - * <code>null</code> otherwise. - */ - public String query() - { - return query; - } - - - /** - * Returns the URI formed from this URI and the given query. - * - * @exception java.lang.IllegalArgumentException if - * <code>query</code> is not a valid query (portion) according - * to {@link #validQuery}. - */ - public URI appendQuery(String query) - { - if (!validQuery(query)) - { - throw new IllegalArgumentException( - "invalid query portion: " + query); - } - return new URI(hierarchical, scheme, authority, device, absolutePath, segments, query, fragment); - } - - /** - * If this URI has a non-null {@link #query}, returns the URI - * formed by removing it; this URI unchanged, otherwise. - */ - public URI trimQuery() - { - if (query == null) - { - return this; - } - else - { - return new URI(hierarchical, scheme, authority, device, absolutePath, segments, null, fragment); - } - } - - /** - * If this URI has a fragment component, returns it; <code>null</code> - * otherwise. - */ - public String fragment() - { - return fragment; - } - - /** - * Returns the URI formed from this URI and the given fragment. - * - * @exception java.lang.IllegalArgumentException if - * <code>fragment</code> is not a valid fragment (portion) according - * to {@link #validFragment}. - */ - public URI appendFragment(String fragment) - { - if (!validFragment(fragment)) - { - throw new IllegalArgumentException( - "invalid fragment portion: " + fragment); - } - URI result = new URI(hierarchical, scheme, authority, device, absolutePath, segments, query, fragment); - result.cachedTrimFragment = this; - return result; - } - - /** - * If this URI has a non-null {@link #fragment}, returns the URI - * formed by removing it; this URI unchanged, otherwise. - */ - public URI trimFragment() - { - if (fragment == null) - { - return this; - } - else if (cachedTrimFragment == null) - { - cachedTrimFragment = new URI(hierarchical, scheme, authority, device, absolutePath, segments, query, null); - } - - return cachedTrimFragment; - } - - /** - * Resolves this URI reference against a <code>base</code> absolute - * hierarchical URI, returning the resulting absolute URI. If already - * absolute, the URI itself is returned. URI resolution is described in - * detail in section 5.2 of <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC - * 2396</a>, "Resolving Relative References to Absolute Form." - * - * <p>During resolution, empty segments, self references ("."), and parent - * references ("..") are interpreted, so that they can be removed from the - * path. Step 6(g) gives a choice of how to handle the case where parent - * references point to a path above the root: the offending segments can - * be preserved or discarded. This method preserves them. To have them - * discarded, please use the {@link #resolve(URI, boolean)} method. - * - * @exception java.lang.IllegalArgumentException if <code>base</code> is - * non-hierarchical or is relative. - */ - public URI resolve(URI base) - { - return resolve(base, true); - } - - /** - * Resolves this URI reference against a <code>base</code> absolute - * hierarchical URI, returning the resulting absolute URI. If already - * absolute, the URI itself is returned. URI resolution is described in - * detail in section 5.2 of <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC - * 2396</a>, "Resolving Relative References to Absolute Form." - * - * <p>During resultion, empty segments, self references ("."), and parent - * references ("..") are interpreted, so that they can be removed from the - * path. Step 6(g) gives a choice of how to handle the case where parent - * references point to a path above the root: the offending segments can - * be preserved or discarded. This method can do either. - * - * @param preserveRootParent <code>true</code> if segments refering to the - * parent of the root path are to be preserved; <code>false</code> if they - * are to be discarded. - * - * @exception java.lang.IllegalArgumentException if <code>base</code> is - * non-hierarchical or is relative. - */ - public URI resolve(URI base, boolean preserveRootParents) - { - if (!base.isHierarchical() || base.isRelative()) - { - throw new IllegalArgumentException( - "resolve against non-hierarchical or relative base"); - } - - // an absolute URI needs no resolving - if (!isRelative()) return this; - - // note: isRelative() -> hierarchical - - String newAuthority = authority; - String newDevice = device; - boolean newAbsolutePath = absolutePath; - String[] newSegments = segments; - String newQuery = query; - // note: it's okay for two URIs to share a segments array, since - // neither will ever modify it - - if (authority == null) - { - // no authority: use base's - newAuthority = base.authority(); - - if (device == null) - { - // no device: use base's - newDevice = base.device(); - - if (hasEmptyPath() && query == null) - { - // current document reference: use base path and query - newAbsolutePath = base.hasAbsolutePath(); - newSegments = base.segments(); - newQuery = base.query(); - } - else if (hasRelativePath()) - { - // relative path: merge with base and keep query (note: if the - // base has no path and this a non-empty relative path, there is - // an implied root in the resulting path) - newAbsolutePath = base.hasAbsolutePath() || !hasEmptyPath(); - newSegments = newAbsolutePath ? mergePath(base, preserveRootParents) - : NO_SEGMENTS; - } - // else absolute path: keep it and query - } - // else keep device, path, and query - } - // else keep authority, device, path, and query - - // always keep fragment, even if null, and use scheme from base - return new URI(true, base.scheme(), newAuthority, newDevice, - newAbsolutePath, newSegments, newQuery, fragment); - } - - // Merges this URI's relative path with the base non-relative path. If - // base has no path, treat it as the root absolute path, unless this has - // no path either. - private String[] mergePath(URI base, boolean preserveRootParents) - { - if (base.hasRelativePath()) - { - throw new IllegalArgumentException("merge against relative path"); - } - if (!hasRelativePath()) - { - throw new IllegalStateException("merge non-relative path"); - } - - int baseSegmentCount = base.segmentCount(); - int segmentCount = segments.length; - String[] stack = new String[baseSegmentCount + segmentCount]; - int sp = 0; - - // use a stack to accumulate segments of base, except for the last - // (i.e. skip trailing separator and anything following it), and of - // relative path - for (int i = 0; i < baseSegmentCount - 1; i++) - { - sp = accumulate(stack, sp, base.segment(i), preserveRootParents); - } - - for (int i = 0; i < segmentCount; i++) - { - sp = accumulate(stack, sp, segments[i], preserveRootParents); - } - - // if the relative path is empty or ends in an empty segment, a parent - // reference, or a self referenfce, add a trailing separator to a - // non-empty path - if (sp > 0 && (segmentCount == 0 || - SEGMENT_EMPTY.equals(segments[segmentCount - 1]) || - SEGMENT_PARENT.equals(segments[segmentCount - 1]) || - SEGMENT_SELF.equals(segments[segmentCount - 1]))) - { - stack[sp++] = SEGMENT_EMPTY; - } - - // return a correctly sized result - String[] result = new String[sp]; - System.arraycopy(stack, 0, result, 0, sp); - return result; - } - - // Adds a segment to a stack, skipping empty segments and self references, - // and interpreting parent references. - private static int accumulate(String[] stack, int sp, String segment, - boolean preserveRootParents) - { - if (SEGMENT_PARENT.equals(segment)) - { - if (sp == 0) - { - // special care must be taken for a root's parent reference: it is - // either ignored or the symbolic reference itself is pushed - if (preserveRootParents) stack[sp++] = segment; - } - else - { - // unless we're already accumulating root parent references, - // parent references simply pop the last segment descended - if (SEGMENT_PARENT.equals(stack[sp - 1])) stack[sp++] = segment; - else sp--; - } - } - else if (!SEGMENT_EMPTY.equals(segment) && !SEGMENT_SELF.equals(segment)) - { - // skip empty segments and self references; push everything else - stack[sp++] = segment; - } - return sp; - } - - /** - * Finds the shortest relative or, if necessary, the absolute URI that, - * when resolved against the given <code>base</code> absolute hierarchical - * URI using {@link #resolve(URI)}, will yield this absolute URI. - * - * @exception java.lang.IllegalArgumentException if <code>base</code> is - * non-hierarchical or is relative. - * @exception java.lang.IllegalStateException if <code>this</code> is - * relative. - */ - public URI deresolve(URI base) - { - return deresolve(base, true, false, true); - } - - /** - * Finds an absolute URI that, when resolved against the given - * <code>base</code> absolute hierarchical URI using {@link #resolve(URI, - * boolean)}, will yield this absolute URI. - * - * @param preserveRootParents the boolean argument to <code>resolve(URI, - * boolean)</code> for which the returned URI should resolve to this URI. - * @param anyRelPath if <code>true</code>, the returned URI's path (if - * any) will be relative, if possible. If <code>false</code>, the form of - * the result's path will depend upon the next parameter. - * @param shorterRelPath if <code>anyRelPath</code> is <code>false</code> - * and this parameter is <code>true</code>, the returned URI's path (if - * any) will be relative, if one can be found that is no longer (by number - * of segments) than the absolute path. If both <code>anyRelPath</code> - * and this parameter are <code>false</code>, it will be absolute. - * - * @exception java.lang.IllegalArgumentException if <code>base</code> is - * non-hierarchical or is relative. - * @exception java.lang.IllegalStateException if <code>this</code> is - * relative. - */ - public URI deresolve(URI base, boolean preserveRootParents, - boolean anyRelPath, boolean shorterRelPath) - { - if (!base.isHierarchical() || base.isRelative()) - { - throw new IllegalArgumentException( - "deresolve against non-hierarchical or relative base"); - } - if (isRelative()) - { - throw new IllegalStateException("deresolve relative URI"); - } - - // note: these assertions imply that neither this nor the base URI has a - // relative path; thus, both have either an absolute path or no path - - // different scheme: need complete, absolute URI - if (!scheme.equals(base.scheme())) return this; - - // since base must be hierarchical, and since a non-hierarchical URI - // must have both scheme and opaque part, the complete absolute URI is - // needed to resolve to a non-hierarchical URI - if (!isHierarchical()) return this; - - String newAuthority = authority; - String newDevice = device; - boolean newAbsolutePath = absolutePath; - String[] newSegments = segments; - String newQuery = query; - - if (equals(authority, base.authority()) && - (hasDevice() || hasPath() || (!base.hasDevice() && !base.hasPath()))) - { - // matching authorities and no device or path removal - newAuthority = null; - - if (equals(device, base.device()) && (hasPath() || !base.hasPath())) - { - // matching devices and no path removal - newDevice = null; - - // exception if (!hasPath() && base.hasPath()) - - if (!anyRelPath && !shorterRelPath) - { - // user rejects a relative path: keep absolute or no path - } - else if (hasPath() == base.hasPath() && segmentsEqual(base) && - equals(query, base.query())) - { - // current document reference: keep no path or query - newAbsolutePath = false; - newSegments = NO_SEGMENTS; - newQuery = null; - } - else if (!hasPath() && !base.hasPath()) - { - // no paths: keep query only - newAbsolutePath = false; - newSegments = NO_SEGMENTS; - } - // exception if (!hasAbsolutePath()) - else if (hasCollapsableSegments(preserveRootParents)) - { - // path form demands an absolute path: keep it and query - } - else - { - // keep query and select relative or absolute path based on length - String[] rel = findRelativePath(base, preserveRootParents); - if (anyRelPath || segments.length > rel.length) - { - // user demands a relative path or the absolute path is longer - newAbsolutePath = false; - newSegments = rel; - } - // else keep shorter absolute path - } - } - // else keep device, path, and query - } - // else keep authority, device, path, and query - - // always include fragment, even if null - return new URI(true, null, newAuthority, newDevice, newAbsolutePath, - newSegments, newQuery, fragment); - } - - // Returns true if the non-relative path includes segments that would be - // collapsed when resolving; false otherwise. If preserveRootParents is - // true, collapsable segments include any empty segments, except for the - // last segment, as well as and parent and self references. If - // preserveRootsParents is false, parent references are not collapsable if - // they are the first segment or preceeded only by other parent - // references. - private boolean hasCollapsableSegments(boolean preserveRootParents) - { - if (hasRelativePath()) - { - throw new IllegalStateException("test collapsability of relative path"); - } - - for (int i = 0, len = segments.length; i < len; i++) - { - String segment = segments[i]; - if ((i < len - 1 && SEGMENT_EMPTY.equals(segment)) || - SEGMENT_SELF.equals(segment) || - SEGMENT_PARENT.equals(segment) && ( - !preserveRootParents || ( - i != 0 && !SEGMENT_PARENT.equals(segments[i - 1])))) - { - return true; - } - } - return false; - } - - // Returns the shortest relative path between the the non-relative path of - // the given base and this absolute path. If the base has no path, it is - // treated as the root absolute path. - private String[] findRelativePath(URI base, boolean preserveRootParents) - { - if (base.hasRelativePath()) - { - throw new IllegalArgumentException( - "find relative path against base with relative path"); - } - if (!hasAbsolutePath()) - { - throw new IllegalArgumentException( - "find relative path of non-absolute path"); - } - - // treat an empty base path as the root absolute path - String[] startPath = base.collapseSegments(preserveRootParents); - String[] endPath = segments; - - // drop last segment from base, as in resolving - int startCount = startPath.length > 0 ? startPath.length - 1 : 0; - int endCount = endPath.length; - - // index of first segment that is different between endPath and startPath - int diff = 0; - - // if endPath is shorter than startPath, the last segment of endPath may - // not be compared: because startPath has been collapsed and had its - // last segment removed, all preceeding segments can be considered non- - // empty and followed by a separator, while the last segment of endPath - // will either be non-empty and not followed by a separator, or just empty - for (int count = startCount < endCount ? startCount : endCount - 1; - diff < count && startPath[diff].equals(endPath[diff]); diff++); - - int upCount = startCount - diff; - int downCount = endCount - diff; - - // a single separator, possibly preceeded by some parent reference - // segments, is redundant - if (downCount == 1 && SEGMENT_EMPTY.equals(endPath[endCount - 1])) - { - downCount = 0; - } - - // an empty path needs to be replaced by a single "." if there is no - // query, to distinguish it from a current document reference - if (upCount + downCount == 0) - { - if (query == null) return new String[] { SEGMENT_SELF }; - return NO_SEGMENTS; - } - - // return a correctly sized result - String[] result = new String[upCount + downCount]; - Arrays.fill(result, 0, upCount, SEGMENT_PARENT); - System.arraycopy(endPath, diff, result, upCount, downCount); - return result; - } - - // Collapses non-ending empty segments, parent references, and self - // references in a non-relative path, returning the same path that would - // be produced from the base hierarchical URI as part of a resolve. - String[] collapseSegments(boolean preserveRootParents) - { - if (hasRelativePath()) - { - throw new IllegalStateException("collapse relative path"); - } - - if (!hasCollapsableSegments(preserveRootParents)) return segments(); - - // use a stack to accumulate segments - int segmentCount = segments.length; - String[] stack = new String[segmentCount]; - int sp = 0; - - for (int i = 0; i < segmentCount; i++) - { - sp = accumulate(stack, sp, segments[i], preserveRootParents); - } - - // if the path is non-empty and originally ended in an empty segment, a - // parent reference, or a self reference, add a trailing separator - if (sp > 0 && (SEGMENT_EMPTY.equals(segments[segmentCount - 1]) || - SEGMENT_PARENT.equals(segments[segmentCount - 1]) || - SEGMENT_SELF.equals(segments[segmentCount - 1]))) - { - stack[sp++] = SEGMENT_EMPTY; - } - - // return a correctly sized result - String[] result = new String[sp]; - System.arraycopy(stack, 0, result, 0, sp); - return result; - } - - /** - * Returns the string representation of this URI. For a generic, - * non-hierarchical URI, this looks like: - * - * <pre> - * scheme:opaquePart#fragment</pre> - * - * <p>For a hierarchical URI, it looks like: - * <pre> - * scheme://authority/device/pathSegment1/pathSegment2...?query#fragment</pre> - * - * <p>Of course, absent components and their separators will be omitted. - */ - public String toString() - { - if (cachedToString == null) - { - StringBuffer result = new StringBuffer(); - if (!isRelative()) - { - result.append(scheme); - result.append(SCHEME_SEPARATOR); - } - - if (isHierarchical()) - { - if (hasAuthority()) - { - result.append(AUTHORITY_SEPARATOR); - result.append(authority); - } - - if (hasDevice()) - { - result.append(SEGMENT_SEPARATOR); - result.append(device); - } - - if (hasAbsolutePath()) result.append(SEGMENT_SEPARATOR); - - for (int i = 0, len = segments.length; i < len; i++) - { - if (i != 0) result.append(SEGMENT_SEPARATOR); - result.append(segments[i]); - } - - if (hasQuery()) - { - result.append(QUERY_SEPARATOR); - result.append(query); - } - } - else - { - result.append(authority); - } - - if (hasFragment()) - { - result.append(FRAGMENT_SEPARATOR); - result.append(fragment); - } - cachedToString = result.toString(); - } - return cachedToString; - } - - // Returns a string representation of this URI for debugging, explicitly - // showing each of the components. - String toString(boolean includeSimpleForm) - { - StringBuffer result = new StringBuffer(); - if (includeSimpleForm) result.append(toString()); - result.append("\n hierarchical: "); - result.append(hierarchical); - result.append("\n scheme: "); - result.append(scheme); - result.append("\n authority: "); - result.append(authority); - result.append("\n device: "); - result.append(device); - result.append("\n absolutePath: "); - result.append(absolutePath); - result.append("\n segments: "); - if (segments.length == 0) result.append("<empty>"); - for (int i = 0, len = segments.length; i < len; i++) - { - if (i > 0) result.append("\n "); - result.append(segments[i]); - } - result.append("\n query: "); - result.append(query); - result.append("\n fragment: "); - result.append(fragment); - return result.toString(); - } - - /** - * If this URI may refer directly to a locally accessible file, as - * determined by {@link #isFile()}, returns the URI formatted as a - * pathname to that file; null otherwise. - * - * <p>The format of this string is - * <pre> - * //authority/device/pathSegment1/pathSegment2...</pre> - * - * <p>However, the character used as a separator is system-dependant and - * obtained from {@link java.io.File#separatorChar}. - */ - public String toFileString() - { - if (!isFile()) return null; - - StringBuffer result = new StringBuffer(); - char separator = File.separatorChar; - - if (hasAuthority()) - { - result.append(separator); - result.append(separator); - result.append(authority); - - if (hasDevice()) result.append(separator); - } - - if (hasDevice()) result.append(device); - if (hasAbsolutePath()) result.append(separator); - - for (int i = 0, len = segments.length; i < len; i++) - { - if (i != 0) result.append(separator); - result.append(segments[i]); - } - return result.toString(); - } - - /** - * Returns the URI formed by appending the specified segment on to the end - * of the path of this URI, if hierarchical; this URI unchanged, - * otherwise. If this URI has an authority and/or device, but no path, - * the segment becomes the first under the root in an absolute path. - * - * @exception java.lang.IllegalArgumentException if <code>segment</code> - * is not a valid segment according to {@link #validSegment}. - */ - public URI appendSegment(String segment) - { - if (!validSegment(segment)) - { - throw new IllegalArgumentException("invalid segment: " + segment); - } - - if (!isHierarchical()) return this; - - // absolute path or no path -> absolute path - boolean newAbsolutePath = !hasRelativePath(); - - int len = segments.length; - String[] newSegments = new String[len + 1]; - System.arraycopy(segments, 0, newSegments, 0, len); - newSegments[len] = segment; - - return new URI(true, scheme, authority, device, newAbsolutePath, - newSegments, query, fragment); - } - - /** - * Returns the URI formed by appending the specified segments on to the - * end of the path of this URI, if hierarchical; this URI unchanged, - * otherwise. If this URI has an authority and/or device, but no path, - * the segments are made to form an absolute path. - * - * @param segments an array of non-null strings, each representing one - * segment of the path. If desired, a trailing separator should be - * represented by an empty-string segment as the last element of the - * array. - * - * @exception java.lang.IllegalArgumentException if <code>segments</code> - * is not a valid segment array according to {@link #validSegments}. - */ - public URI appendSegments(String[] segments) - { - if (!validSegments(segments)) - { - String s = segments == null ? "invalid segments: " + segments : - "invalid segment: " + firstInvalidSegment(segments); - throw new IllegalArgumentException(s); - } - - if (!isHierarchical()) return this; - - // absolute path or no path -> absolute path - boolean newAbsolutePath = !hasRelativePath(); - - int len = this.segments.length; - int segmentsCount = segments.length; - String[] newSegments = new String[len + segmentsCount]; - System.arraycopy(this.segments, 0, newSegments, 0, len); - System.arraycopy(segments, 0, newSegments, len, segmentsCount); - - return new URI(true, scheme, authority, device, newAbsolutePath, - newSegments, query, fragment); - } - - /** - * Returns the URI formed by trimming the specified number of segments - * (including empty segments, such as one representing a trailing - * separator) from the end of the path of this URI, if hierarchical; - * otherwise, this URI is returned unchanged. - * - * <p>Note that if all segments are trimmed from an absolute path, the - * root absolute path remains. - * - * @param i the number of segments to be trimmed in the returned URI. If - * less than 1, this URI is returned unchanged; if equal to or greater - * than the number of segments in this URI's path, all segments are - * trimmed. - */ - public URI trimSegments(int i) - { - if (!isHierarchical() || i < 1) return this; - - String[] newSegments = NO_SEGMENTS; - int len = segments.length - i; - if (len > 0) - { - newSegments = new String[len]; - System.arraycopy(segments, 0, newSegments, 0, len); - } - return new URI(true, scheme, authority, device, absolutePath, - newSegments, query, fragment); - } - - /** - * Returns <code>true</code> if this is a hierarchical URI that has a path - * that ends with a trailing separator; <code>false</code> otherwise. - * - * <p>A trailing separator is represented as an empty segment as the - * last segment in the path; note that this definition does <em>not</em> - * include the lone separator in the root absolute path. - */ - public boolean hasTrailingPathSeparator() - { - return segments.length > 0 && - SEGMENT_EMPTY.equals(segments[segments.length - 1]); - } - - /** - * If this is a hierarchical URI whose path includes a file extension, - * that file extension is returned; null otherwise. We define a file - * extension as any string following the last period (".") in the final - * path segment. If there is no path, the path ends in a trailing - * separator, or the final segment contains no period, then we consider - * there to be no file extension. If the final segment ends in a period, - * then the file extension is an empty string. - */ - public String fileExtension() - { - int len = segments.length; - if (len == 0) return null; - - String lastSegment = segments[len - 1]; - int i = lastSegment.lastIndexOf(FILE_EXTENSION_SEPARATOR); - return i < 0 ? null : lastSegment.substring(i + 1); - } - - /** - * Returns the URI formed by appending a period (".") followed by the - * specified file extension to the last path segment of this URI, if it is - * hierarchical with a non-empty path ending in a non-empty segment; - * otherwise, this URI is returned unchanged. - - * <p>The extension is appended regardless of whether the segment already - * contains an extension. - * - * @exception java.lang.IllegalArgumentException if - * <code>fileExtension</code> is not a valid segment (portion) according - * to {@link #validSegment}. - */ - public URI appendFileExtension(String fileExtension) - { - if (!validSegment(fileExtension)) - { - throw new IllegalArgumentException( - "invalid segment portion: " + fileExtension); - } - - int len = segments.length; - if (len == 0) return this; - - String lastSegment = segments[len - 1]; - if (SEGMENT_EMPTY.equals(lastSegment)) return this; - StringBuffer newLastSegment = new StringBuffer(lastSegment); - newLastSegment.append(FILE_EXTENSION_SEPARATOR); - newLastSegment.append(fileExtension); - - String[] newSegments = new String[len]; - System.arraycopy(segments, 0, newSegments, 0, len - 1); - newSegments[len - 1] = newLastSegment.toString(); - - // note: segments.length > 0 -> hierarchical - return new URI(true, scheme, authority, device, absolutePath, - newSegments, query, fragment); - } - - /** - * If this URI has a non-null {@link #fileExtension}, returns the URI - * formed by removing it; this URI unchanged, otherwise. - */ - public URI trimFileExtension() - { - int len = segments.length; - if (len == 0) return this; - - String lastSegment = segments[len - 1]; - int i = lastSegment.lastIndexOf(FILE_EXTENSION_SEPARATOR); - if (i < 0) return this; - - String newLastSegment = lastSegment.substring(0, i); - String[] newSegments = new String[len]; - System.arraycopy(segments, 0, newSegments, 0, len - 1); - newSegments[len - 1] = newLastSegment; - - // note: segments.length > 0 -> hierarchical - return new URI(true, scheme, authority, device, absolutePath, - newSegments, query, fragment); - } - - /** - * Returns <code>true</code> if this is a hierarchical URI that ends in a - * slash; that is, it has a trailing path separator or is the root - * absolute path, and has no query and no fragment; <code>false</code> - * is returned otherwise. - */ - public boolean isPrefix() - { - return hierarchical && query == null && fragment == null && - (hasTrailingPathSeparator() || (absolutePath && segments.length == 0)); - } - - /** - * If this is a hierarchical URI reference and <code>oldPrefix</code> is a - * prefix of it, this returns the URI formed by replacing it by - * <code>newPrefix</code>; <code>null</code> otherwise. - * - * <p>In order to be a prefix, the <code>oldPrefix</code>'s - * {@link #isPrefix} must return <code>true</code>, and it must match this - * URI's scheme, authority, and device. Also, the paths must match, up to - * prefix's end. - * - * @exception java.lang.IllegalArgumentException if either - * <code>oldPrefix</code> or <code>newPrefix</code> is not a prefix URI - * according to {@link #isPrefix}. - */ - public URI replacePrefix(URI oldPrefix, URI newPrefix) - { - if (!oldPrefix.isPrefix() || !newPrefix.isPrefix()) - { - String which = oldPrefix.isPrefix() ? "new" : "old"; - throw new IllegalArgumentException("non-prefix " + which + " value"); - } - - // Get what's left of the segments after trimming the prefix. - String[] tailSegments = getTailSegments(oldPrefix); - if (tailSegments == null) return null; - - // If the new prefix has segments, it is not the root absolute path, - // and we need to drop the trailing empty segment and append the tail - // segments. - String[] mergedSegments = tailSegments; - if (newPrefix.segmentCount() != 0) - { - int segmentsToKeep = newPrefix.segmentCount() - 1; - mergedSegments = new String[segmentsToKeep + tailSegments.length]; - System.arraycopy(newPrefix.segments(), 0, mergedSegments, 0, - segmentsToKeep); - - if (tailSegments.length != 0) - { - System.arraycopy(tailSegments, 0, mergedSegments, segmentsToKeep, - tailSegments.length); - } - } - - return new URI(true, newPrefix.scheme(), newPrefix.authority(), - newPrefix.device(), newPrefix.hasAbsolutePath(), - mergedSegments, query, fragment); - } - - // If this is a hierarchical URI reference and prefix is a prefix of it, - // returns the portion of the path remaining after that prefix has been - // trimmed; null otherwise. - private String[] getTailSegments(URI prefix) - { - if (!prefix.isPrefix()) - { - throw new IllegalArgumentException("non-prefix trim"); - } - - // Don't even consider it unless this is hierarchical and has scheme, - // authority, device and path absoluteness equal to those of the prefix. - if (!hierarchical || - !equals(scheme, prefix.scheme()) || - !equals(authority, prefix.authority()) || - !equals(device, prefix.device()) || - absolutePath != prefix.hasAbsolutePath()) - { - return null; - } - - // If the prefix has no segments, then it is the root absolute path, and - // we know this is an absolute path, too. - if (prefix.segmentCount() == 0) return segments; - - // This must have no fewer segments than the prefix. Since the prefix - // is not the root absolute path, its last segment is empty; all others - // must match. - int i = 0; - int segmentsToCompare = prefix.segmentCount() - 1; - if (segments.length <= segmentsToCompare) return null; - - for (; i < segmentsToCompare; i++) - { - if (!segments[i].equals(prefix.segment(i))) return null; - } - - // The prefix really is a prefix of this. If this has just one more, - // empty segment, the paths are the same. - if (i == segments.length - 1 && SEGMENT_EMPTY.equals(segments[i])) - { - return NO_SEGMENTS; - } - - // Otherwise, the path needs only the remaining segments. - String[] newSegments = new String[segments.length - i]; - System.arraycopy(segments, i, newSegments, 0, newSegments.length); - return newSegments; - } -} |