Add observatory_pub_packages snapshot to third_party

observatory_pub_packages/analyzer/src/generated/source.dart

Index: observatory_pub_packages/analyzer/src/generated/source.dart
===================================================================
--- observatory_pub_packages/analyzer/src/generated/source.dart	(revision 0)
+++ observatory_pub_packages/analyzer/src/generated/source.dart	(working copy)
@@ -0,0 +1,919 @@
+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// This code was auto-generated, is not intended to be edited, and is subject to
+// significant change. Please see the README file for more information.
+
+library engine.source;
+
+import 'dart:collection';
+import 'java_core.dart';
+import 'sdk.dart' show DartSdk;
+import 'engine.dart';
+import 'java_engine.dart';
+
+/**
+ * Instances of class `ContentCache` hold content used to override the default content of a
+ * [Source].
+ */
+class ContentCache {
+  /**
+   * A table mapping sources to the contents of those sources. This is used to override the default
+   * contents of a source.
+   */
+  HashMap<Source, String> _contentMap = new HashMap<Source, String>();
+
+  /**
+   * A table mapping sources to the modification stamps of those sources. This is used when the
+   * default contents of a source has been overridden.
+   */
+  HashMap<Source, int> _stampMap = new HashMap<Source, int>();
+
+  /**
+   * Return the contents of the given source, or `null` if this cache does not override the
+   * contents of the source.
+   *
+   * <b>Note:</b> This method is not intended to be used except by
+   * [AnalysisContext#getContents].
+   *
+   * @param source the source whose content is to be returned
+   * @return the contents of the given source
+   */
+  String getContents(Source source) => _contentMap[source];
+
+  /**
+   * Return the modification stamp of the given source, or `null` if this cache does not
+   * override the contents of the source.
+   *
+   * <b>Note:</b> This method is not intended to be used except by
+   * [AnalysisContext#getModificationStamp].
+   *
+   * @param source the source whose modification stamp is to be returned
+   * @return the modification stamp of the given source
+   */
+  int getModificationStamp(Source source) => _stampMap[source];
+
+  /**
+   * Set the contents of the given source to the given contents. This has the effect of overriding
+   * the default contents of the source. If the contents are `null` the override is removed so
+   * that the default contents will be returned.
+   *
+   * @param source the source whose contents are being overridden
+   * @param contents the new contents of the source
+   * @return the original cached contents or `null` if none
+   */
+  String setContents(Source source, String contents) {
+    if (contents == null) {
+      _stampMap.remove(source);
+      return _contentMap.remove(source);
+    } else {
+      int newStamp = JavaSystem.currentTimeMillis();
+      int oldStamp = javaMapPut(_stampMap, source, newStamp);
+      // Occasionally, if this method is called in rapid succession, the timestamps are equal.
+      // Guard against this by artificially incrementing the new timestamp
+      if (newStamp == oldStamp) {
+        _stampMap[source] = newStamp + 1;
+      }
+      return javaMapPut(_contentMap, source, contents);
+    }
+  }
+}
+
+/**
+ * Instances of the class `DartUriResolver` resolve `dart` URI's.
+ */
+class DartUriResolver extends UriResolver {
+  /**
+   * Return `true` if the given URI is a `dart-ext:` URI.
+   *
+   * @param uriContent the textual representation of the URI being tested
+   * @return `true` if the given URI is a `dart-ext:` URI
+   */
+  static bool isDartExtUri(String uriContent) => uriContent != null && uriContent.startsWith(_DART_EXT_SCHEME);
+
+  /**
+   * The Dart SDK against which URI's are to be resolved.
+   */
+  final DartSdk _sdk;
+
+  /**
+   * The name of the `dart` scheme.
+   */
+  static String DART_SCHEME = "dart";
+
+  /**
+   * The prefix of a URI using the dart-ext scheme to reference a native code library.
+   */
+  static String _DART_EXT_SCHEME = "dart-ext:";
+
+  /**
+   * Return `true` if the given URI is a `dart:` URI.
+   *
+   * @param uri the URI being tested
+   * @return `true` if the given URI is a `dart:` URI
+   */
+  static bool isDartUri(Uri uri) => DART_SCHEME == uri.scheme;
+
+  /**
+   * Initialize a newly created resolver to resolve Dart URI's against the given platform within the
+   * given Dart SDK.
+   *
+   * @param sdk the Dart SDK against which URI's are to be resolved
+   */
+  DartUriResolver(this._sdk);
+
+  /**
+   * Return the [DartSdk] against which URIs are to be resolved.
+   *
+   * @return the [DartSdk] against which URIs are to be resolved.
+   */
+  DartSdk get dartSdk => _sdk;
+
+  @override
+  Source resolveAbsolute(Uri uri) {
+    if (!isDartUri(uri)) {
+      return null;
+    }
+    return _sdk.mapDartUri(uri.toString());
+  }
+}
+
+/**
+ * Instances of the class `LineInfo` encapsulate information about line and column information
+ * within a source file.
+ */
+class LineInfo {
+  /**
+   * An array containing the offsets of the first character of each line in the source code.
+   */
+  final List<int> _lineStarts;
+
+  /**
+   * Initialize a newly created set of line information to represent the data encoded in the given
+   * array.
+   *
+   * @param lineStarts the offsets of the first character of each line in the source code
+   */
+  LineInfo(this._lineStarts) {
+    if (_lineStarts == null) {
+      throw new IllegalArgumentException("lineStarts must be non-null");
+    } else if (_lineStarts.length < 1) {
+      throw new IllegalArgumentException("lineStarts must be non-empty");
+    }
+  }
+
+  /**
+   * Return the location information for the character at the given offset.
+   *
+   * @param offset the offset of the character for which location information is to be returned
+   * @return the location information for the character at the given offset
+   */
+  LineInfo_Location getLocation(int offset) {
+    int lineCount = _lineStarts.length;
+    for (int i = 1; i < lineCount; i++) {
+      if (offset < _lineStarts[i]) {
+        return new LineInfo_Location(i, offset - _lineStarts[i - 1] + 1);
+      }
+    }
+    return new LineInfo_Location(lineCount, offset - _lineStarts[lineCount - 1] + 1);
+  }
+}
+
+/**
+ * Instances of the class `Location` represent the location of a character as a line and
+ * column pair.
+ */
+class LineInfo_Location {
+  /**
+   * The one-based index of the line containing the character.
+   */
+  final int lineNumber;
+
+  /**
+   * The one-based index of the column containing the character.
+   */
+  final int columnNumber;
+
+  /**
+   * Initialize a newly created location to represent the location of the character at the given
+   * line and column position.
+   *
+   * @param lineNumber the one-based index of the line containing the character
+   * @param columnNumber the one-based index of the column containing the character
+   */
+  LineInfo_Location(this.lineNumber, this.columnNumber);
+}
+
+/**
+ * Instances of interface `LocalSourcePredicate` are used to determine if the given
+ * [Source] is "local" in some sense, so can be updated.
+ */
+abstract class LocalSourcePredicate {
+  /**
+   * Instance of [LocalSourcePredicate] that always returns `false`.
+   */
+  static final LocalSourcePredicate FALSE = new LocalSourcePredicate_FALSE();
+
+  /**
+   * Instance of [LocalSourcePredicate] that always returns `true`.
+   */
+  static final LocalSourcePredicate TRUE = new LocalSourcePredicate_TRUE();
+
+  /**
+   * Instance of [LocalSourcePredicate] that returns `true` for all [Source]s
+   * except of SDK.
+   */
+  static final LocalSourcePredicate NOT_SDK = new LocalSourcePredicate_NOT_SDK();
+
+  /**
+   * Determines if the given [Source] is local.
+   *
+   * @param source the [Source] to analyze
+   * @return `true` if the given [Source] is local
+   */
+  bool isLocal(Source source);
+}
+
+class LocalSourcePredicate_FALSE implements LocalSourcePredicate {
+  @override
+  bool isLocal(Source source) => false;
+}
+
+class LocalSourcePredicate_NOT_SDK implements LocalSourcePredicate {
+  @override
+  bool isLocal(Source source) => source.uriKind != UriKind.DART_URI;
+}
+
+class LocalSourcePredicate_TRUE implements LocalSourcePredicate {
+  @override
+  bool isLocal(Source source) => true;
+}
+
+/**
+ * An implementation of an non-existing [Source].
+ */
+class NonExistingSource implements Source {
+  final String _name;
+
+  final UriKind uriKind;
+
+  NonExistingSource(this._name, this.uriKind);
+
+  @override
+  bool operator ==(Object obj) {
+    if (obj is NonExistingSource) {
+      NonExistingSource other = obj;
+      return other.uriKind == uriKind && (other._name == _name);
+    }
+    return false;
+  }
+
+  @override
+  bool exists() => false;
+
+  @override
+  TimestampedData<String> get contents {
+    throw new UnsupportedOperationException("${_name}does not exist.");
+  }
+
+  @override
+  String get encoding {
+    throw new UnsupportedOperationException("${_name}does not exist.");
+  }
+
+  @override
+  String get fullName => _name;
+
+  @override
+  int get modificationStamp => 0;
+
+  @override
+  String get shortName => _name;
+
+  @override
+  Uri get uri => null;
+
+  @override
+  int get hashCode => _name.hashCode;
+
+  @override
+  bool get isInSystemLibrary => false;
+
+  @override
+  Uri resolveRelativeUri(Uri relativeUri) {
+    throw new UnsupportedOperationException("${_name}does not exist.");
+  }
+}
+
+/**
+ * The interface `Source` defines the behavior of objects representing source code that can be
+ * analyzed by the analysis engine.
+ *
+ * Implementations of this interface need to be aware of some assumptions made by the analysis
+ * engine concerning sources:
+ * * Sources are not required to be unique. That is, there can be multiple instances representing
+ * the same source.
+ * * Sources are long lived. That is, the engine is allowed to hold on to a source for an extended
+ * period of time and that source must continue to report accurate and up-to-date information.
+ * Because of these assumptions, most implementations will not maintain any state but will delegate
+ * to an authoritative system of record in order to implement this API. For example, a source that
+ * represents files on disk would typically query the file system to determine the state of the
+ * file.
+ *
+ * If the instances that implement this API are the system of record, then they will typically be
+ * unique. In that case, sources that are created that represent non-existent files must also be
+ * retained so that if those files are created at a later date the long-lived sources representing
+ * those files will know that they now exist.
+ */
+abstract class Source {
+  /**
+   * An empty array of sources.
+   */
+  static final List<Source> EMPTY_ARRAY = new List<Source>(0);
+
+  /**
+   * Return `true` if the given object is a source that represents the same source code as
+   * this source.
+   *
+   * @param object the object to be compared with this object
+   * @return `true` if the given object is a source that represents the same source code as
+   *         this source
+   * @see Object#equals(Object)
+   */
+  @override
+  bool operator ==(Object object);
+
+  /**
+   * Return `true` if this source exists.
+   *
+   * Clients should consider using the the method [AnalysisContext#exists] because
+   * contexts can have local overrides of the content of a source that the source is not aware of
+   * and a source with local content is considered to exist even if there is no file on disk.
+   *
+   * @return `true` if this source exists
+   */
+  bool exists();
+
+  /**
+   * Get the contents and timestamp of this source.
+   *
+   * Clients should consider using the the method [AnalysisContext#getContents]
+   * because contexts can have local overrides of the content of a source that the source is not
+   * aware of.
+   *
+   * @return the contents and timestamp of the source
+   * @throws Exception if the contents of this source could not be accessed
+   */
+  TimestampedData<String> get contents;
+
+  /**
+   * Return an encoded representation of this source that can be used to create a source that is
+   * equal to this source.
+   *
+   * @return an encoded representation of this source
+   * @see SourceFactory#fromEncoding(String)
+   */
+  String get encoding;
+
+  /**
+   * Return the full (long) version of the name that can be displayed to the user to denote this
+   * source. For example, for a source representing a file this would typically be the absolute path
+   * of the file.
+   *
+   * @return a name that can be displayed to the user to denote this source
+   */
+  String get fullName;
+
+  /**
+   * Return the modification stamp for this source. A modification stamp is a non-negative integer
+   * with the property that if the contents of the source have not been modified since the last time
+   * the modification stamp was accessed then the same value will be returned, but if the contents
+   * of the source have been modified one or more times (even if the net change is zero) the stamps
+   * will be different.
+   *
+   * Clients should consider using the the method
+   * [AnalysisContext#getModificationStamp] because contexts can have local overrides
+   * of the content of a source that the source is not aware of.
+   *
+   * @return the modification stamp for this source
+   */
+  int get modificationStamp;
+
+  /**
+   * Return a short version of the name that can be displayed to the user to denote this source. For
+   * example, for a source representing a file this would typically be the name of the file.
+   *
+   * @return a name that can be displayed to the user to denote this source
+   */
+  String get shortName;
+
+  /**
+   * Return the URI from which this source was originally derived.
+   *
+   * @return the URI from which this source was originally derived
+   */
+  Uri get uri;
+
+  /**
+   * Return the kind of URI from which this source was originally derived. If this source was
+   * created from an absolute URI, then the returned kind will reflect the scheme of the absolute
+   * URI. If it was created from a relative URI, then the returned kind will be the same as the kind
+   * of the source against which the relative URI was resolved.
+   *
+   * @return the kind of URI from which this source was originally derived
+   */
+  UriKind get uriKind;
+
+  /**
+   * Return a hash code for this source.
+   *
+   * @return a hash code for this source
+   * @see Object#hashCode()
+   */
+  @override
+  int get hashCode;
+
+  /**
+   * Return `true` if this source is in one of the system libraries.
+   *
+   * @return `true` if this is in a system library
+   */
+  bool get isInSystemLibrary;
+
+  /**
+   * Resolve the relative URI against the URI associated with this source object.
+   *
+   * Note: This method is not intended for public use, it is only visible out of necessity. It is
+   * only intended to be invoked by a [SourceFactory]. Source factories will
+   * only invoke this method if the URI is relative, so implementations of this method are not
+   * required to, and generally do not, verify the argument. The result of invoking this method with
+   * an absolute URI is intentionally left unspecified.
+   *
+   * @param relativeUri the relative URI to be resolved against this source
+   * @return the URI to which given URI was resolved
+   * @throws AnalysisException if the relative URI could not be resolved
+   */
+  Uri resolveRelativeUri(Uri relativeUri);
+}
+
+/**
+ * The interface `SourceContainer` is used by clients to define a collection of sources
+ *
+ * Source containers are not used within analysis engine, but can be used by clients to group
+ * sources for the purposes of accessing composite dependency information. For example, the Eclipse
+ * client uses source containers to represent Eclipse projects, which allows it to easily compute
+ * project-level dependencies.
+ */
+abstract class SourceContainer {
+  /**
+   * Determine if the specified source is part of the receiver's collection of sources.
+   *
+   * @param source the source in question
+   * @return `true` if the receiver contains the source, else `false`
+   */
+  bool contains(Source source);
+}
+
+/**
+ * Instances of the class `SourceFactory` resolve possibly relative URI's against an existing
+ * [Source].
+ */
+class SourceFactory {
+  /**
+   * The analysis context that this source factory is associated with.
+   */
+  AnalysisContext context;
+
+  /**
+   * The resolvers used to resolve absolute URI's.
+   */
+  final List<UriResolver> _resolvers;
+
+  /**
+   * The predicate to determine is [Source] is local.
+   */
+  LocalSourcePredicate _localSourcePredicate = LocalSourcePredicate.NOT_SDK;
+
+  /**
+   * Initialize a newly created source factory.
+   *
+   * @param resolvers the resolvers used to resolve absolute URI's
+   */
+  SourceFactory(this._resolvers);
+
+  /**
+   * Return a source object representing the given absolute URI, or `null` if the URI is not a
+   * valid URI or if it is not an absolute URI.
+   *
+   * @param absoluteUri the absolute URI to be resolved
+   * @return a source object representing the absolute URI
+   */
+  Source forUri(String absoluteUri) {
+    try {
+      Uri uri = parseUriWithException(absoluteUri);
+      if (uri.isAbsolute) {
+        return _internalResolveUri(null, uri);
+      }
+    } catch (exception) {
+      AnalysisEngine.instance.logger.logError2("Could not resolve URI: ${absoluteUri}", exception);
+    }
+    return null;
+  }
+
+  /**
+   * Return a source object representing the given absolute URI, or `null` if the URI is not
+   * an absolute URI.
+   *
+   * @param absoluteUri the absolute URI to be resolved
+   * @return a source object representing the absolute URI
+   */
+  Source forUri2(Uri absoluteUri) {
+    if (absoluteUri.isAbsolute) {
+      try {
+        return _internalResolveUri(null, absoluteUri);
+      } on AnalysisException catch (exception, stackTrace) {
+        AnalysisEngine.instance.logger.logError2("Could not resolve URI: ${absoluteUri}", new CaughtException(exception, stackTrace));
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Return a source object that is equal to the source object used to obtain the given encoding.
+   *
+   * @param encoding the encoding of a source object
+   * @return a source object that is described by the given encoding
+   * @throws IllegalArgumentException if the argument is not a valid encoding
+   * @see Source#getEncoding()
+   */
+  Source fromEncoding(String encoding) {
+    Source source = forUri(encoding);
+    if (source == null) {
+      throw new IllegalArgumentException("Invalid source encoding: ${encoding}");
+    }
+    return source;
+  }
+
+  /**
+   * Return the [DartSdk] associated with this [SourceFactory], or `null` if there
+   * is no such SDK.
+   *
+   * @return the [DartSdk] associated with this [SourceFactory], or `null` if
+   *         there is no such SDK
+   */
+  DartSdk get dartSdk {
+    for (UriResolver resolver in _resolvers) {
+      if (resolver is DartUriResolver) {
+        DartUriResolver dartUriResolver = resolver;
+        return dartUriResolver.dartSdk;
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Determines if the given [Source] is local.
+   *
+   * @param source the [Source] to analyze
+   * @return `true` if the given [Source] is local
+   */
+  bool isLocalSource(Source source) => _localSourcePredicate.isLocal(source);
+
+  /**
+   * Return a source object representing the URI that results from resolving the given (possibly
+   * relative) contained URI against the URI associated with an existing source object, whether or
+   * not the resulting source exists, or `null` if either the contained URI is invalid or if
+   * it cannot be resolved against the source object's URI.
+   *
+   * @param containingSource the source containing the given URI
+   * @param containedUri the (possibly relative) URI to be resolved against the containing source
+   * @return the source representing the contained URI
+   */
+  Source resolveUri(Source containingSource, String containedUri) {
+    if (containedUri == null || containedUri.isEmpty) {
+      return null;
+    }
+    try {
+      // Force the creation of an escaped URI to deal with spaces, etc.
+      return _internalResolveUri(containingSource, parseUriWithException(containedUri));
+    } catch (exception) {
+      AnalysisEngine.instance.logger.logError2("Could not resolve URI (${containedUri}) relative to source (${containingSource.fullName})", exception);
+      return null;
+    }
+  }
+
+  /**
+   * Return an absolute URI that represents the given source, or `null` if a valid URI cannot
+   * be computed.
+   *
+   * @param source the source to get URI for
+   * @return the absolute URI representing the given source
+   */
+  Uri restoreUri(Source source) {
+    for (UriResolver resolver in _resolvers) {
+      Uri uri = resolver.restoreAbsolute(source);
+      if (uri != null) {
+        return uri;
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Sets the [LocalSourcePredicate].
+   *
+   * @param localSourcePredicate the predicate to determine is [Source] is local
+   */
+  void set localSourcePredicate(LocalSourcePredicate localSourcePredicate) {
+    this._localSourcePredicate = localSourcePredicate;
+  }
+
+  /**
+   * Return a source object representing the URI that results from resolving the given (possibly
+   * relative) contained URI against the URI associated with an existing source object, or
+   * `null` if the URI could not be resolved.
+   *
+   * @param containingSource the source containing the given URI
+   * @param containedUri the (possibly relative) URI to be resolved against the containing source
+   * @return the source representing the contained URI
+   * @throws AnalysisException if either the contained URI is invalid or if it cannot be resolved
+   *           against the source object's URI
+   */
+  Source _internalResolveUri(Source containingSource, Uri containedUri) {
+    if (!containedUri.isAbsolute) {
+      if (containingSource == null) {
+        throw new AnalysisException("Cannot resolve a relative URI without a containing source: ${containedUri}");
+      }
+      containedUri = containingSource.resolveRelativeUri(containedUri);
+    }
+    for (UriResolver resolver in _resolvers) {
+      Source result = resolver.resolveAbsolute(containedUri);
+      if (result != null) {
+        return result;
+      }
+    }
+    return null;
+  }
+}
+
+/**
+ * The enumeration `SourceKind` defines the different kinds of sources that are known to the
+ * analysis engine.
+ */
+class SourceKind extends Enum<SourceKind> {
+  /**
+   * A source containing HTML. The HTML might or might not contain Dart scripts.
+   */
+  static const SourceKind HTML = const SourceKind('HTML', 0);
+
+  /**
+   * A Dart compilation unit that is not a part of another library. Libraries might or might not
+   * contain any directives, including a library directive.
+   */
+  static const SourceKind LIBRARY = const SourceKind('LIBRARY', 1);
+
+  /**
+   * A Dart compilation unit that is part of another library. Parts contain a part-of directive.
+   */
+  static const SourceKind PART = const SourceKind('PART', 2);
+
+  /**
+   * An unknown kind of source. Used both when it is not possible to identify the kind of a source
+   * and also when the kind of a source is not known without performing a computation and the client
+   * does not want to spend the time to identify the kind.
+   */
+  static const SourceKind UNKNOWN = const SourceKind('UNKNOWN', 3);
+
+  static const List<SourceKind> values = const [HTML, LIBRARY, PART, UNKNOWN];
+
+  const SourceKind(String name, int ordinal) : super(name, ordinal);
+}
+
+/**
+ * A source range defines an [Element]'s source coordinates relative to its [Source].
+ */
+class SourceRange {
+  /**
+   * An empty [SourceRange] with offset `0` and length `0`.
+   */
+  static SourceRange EMPTY = new SourceRange(0, 0);
+
+  /**
+   * The 0-based index of the first character of the source code for this element, relative to the
+   * source buffer in which this element is contained.
+   */
+  final int offset;
+
+  /**
+   * The number of characters of the source code for this element, relative to the source buffer in
+   * which this element is contained.
+   */
+  final int length;
+
+  /**
+   * Initialize a newly created source range using the given offset and the given length.
+   *
+   * @param offset the given offset
+   * @param length the given length
+   */
+  SourceRange(this.offset, this.length);
+
+  /**
+   * @return `true` if <code>x</code> is in [offset, offset + length) interval.
+   */
+  bool contains(int x) => offset <= x && x < offset + length;
+
+  /**
+   * @return `true` if <code>x</code> is in (offset, offset + length) interval.
+   */
+  bool containsExclusive(int x) => offset < x && x < offset + length;
+
+  /**
+   * @return `true` if <code>otherRange</code> covers this [SourceRange].
+   */
+  bool coveredBy(SourceRange otherRange) => otherRange.covers(this);
+
+  /**
+   * @return `true` if this [SourceRange] covers <code>otherRange</code>.
+   */
+  bool covers(SourceRange otherRange) => offset <= otherRange.offset && otherRange.end <= end;
+
+  /**
+   * @return `true` if this [SourceRange] ends in <code>otherRange</code>.
+   */
+  bool endsIn(SourceRange otherRange) {
+    int thisEnd = end;
+    return otherRange.contains(thisEnd);
+  }
+
+  @override
+  bool operator ==(Object obj) {
+    if (obj is! SourceRange) {
+      return false;
+    }
+    SourceRange sourceRange = obj as SourceRange;
+    return sourceRange.offset == offset && sourceRange.length == length;
+  }
+
+  /**
+   * @return the 0-based index of the after-last character of the source code for this element,
+   *         relative to the source buffer in which this element is contained.
+   */
+  int get end => offset + length;
+
+  /**
+   * @return the expanded instance of [SourceRange], which has the same center.
+   */
+  SourceRange getExpanded(int delta) => new SourceRange(offset - delta, delta + length + delta);
+
+  /**
+   * @return the instance of [SourceRange] with end moved on "delta".
+   */
+  SourceRange getMoveEnd(int delta) => new SourceRange(offset, length + delta);
+
+  /**
+   * @return the expanded translated of [SourceRange], with moved start and the same length.
+   */
+  SourceRange getTranslated(int delta) => new SourceRange(offset + delta, length);
+
+  /**
+   * @return the minimal [SourceRange] that cover this and the given [SourceRange]s.
+   */
+  SourceRange getUnion(SourceRange other) {
+    int newOffset = Math.min(offset, other.offset);
+    int newEnd = Math.max(offset + length, other.offset + other.length);
+    return new SourceRange(newOffset, newEnd - newOffset);
+  }
+
+  @override
+  int get hashCode => 31 * offset + length;
+
+  /**
+   * @return `true` if this [SourceRange] intersects with given.
+   */
+  bool intersects(SourceRange other) {
+    if (other == null) {
+      return false;
+    }
+    if (end <= other.offset) {
+      return false;
+    }
+    if (offset >= other.end) {
+      return false;
+    }
+    return true;
+  }
+
+  /**
+   * @return `true` if this [SourceRange] starts in <code>otherRange</code>.
+   */
+  bool startsIn(SourceRange otherRange) => otherRange.contains(offset);
+
+  @override
+  String toString() {
+    JavaStringBuilder builder = new JavaStringBuilder();
+    builder.append("[offset=");
+    builder.append(offset);
+    builder.append(", length=");
+    builder.append(length);
+    builder.append("]");
+    return builder.toString();
+  }
+}
+
+/**
+ * The interface `ContentReceiver` defines the behavior of objects that can receive the
+ * content of a source.
+ */
+abstract class Source_ContentReceiver {
+  /**
+   * Accept the contents of a source.
+   *
+   * @param contents the contents of the source
+   * @param modificationTime the time at which the contents were last set
+   */
+  void accept(String contents, int modificationTime);
+}
+
+/**
+ * The enumeration `UriKind` defines the different kinds of URI's that are known to the
+ * analysis engine. These are used to keep track of the kind of URI associated with a given source.
+ */
+class UriKind extends Enum<UriKind> {
+  /**
+   * A 'dart:' URI.
+   */
+  static const UriKind DART_URI = const UriKind('DART_URI', 0, 0x64);
+
+  /**
+   * A 'file:' URI.
+   */
+  static const UriKind FILE_URI = const UriKind('FILE_URI', 1, 0x66);
+
+  /**
+   * A 'package:' URI.
+   */
+  static const UriKind PACKAGE_URI = const UriKind('PACKAGE_URI', 2, 0x70);
+
+  static const List<UriKind> values = const [DART_URI, FILE_URI, PACKAGE_URI];
+
+  /**
+   * Return the URI kind represented by the given encoding, or `null` if there is no kind with
+   * the given encoding.
+   *
+   * @param encoding the single character encoding used to identify the URI kind to be returned
+   * @return the URI kind represented by the given encoding
+   */
+  static UriKind fromEncoding(int encoding) {
+    while (true) {
+      if (encoding == 0x64) {
+        return DART_URI;
+      } else if (encoding == 0x66) {
+        return FILE_URI;
+      } else if (encoding == 0x70) {
+        return PACKAGE_URI;
+      }
+      break;
+    }
+    return null;
+  }
+
+  /**
+   * The single character encoding used to identify this kind of URI.
+   */
+  final int encoding;
+
+  /**
+   * Initialize a newly created URI kind to have the given encoding.
+   *
+   * @param encoding the single character encoding used to identify this kind of URI.
+   */
+  const UriKind(String name, int ordinal, this.encoding) : super(name, ordinal);
+}
+
+/**
+ * The abstract class `UriResolver` defines the behavior of objects that are used to resolve
+ * URI's for a source factory. Subclasses of this class are expected to resolve a single scheme of
+ * absolute URI.
+ */
+abstract class UriResolver {
+  /**
+   * Resolve the given absolute URI. Return a [Source] representing the file to which
+   * it was resolved, whether or not the resulting source exists, or `null` if it could not be
+   * resolved because the URI is invalid.
+   *
+   * @param uri the URI to be resolved
+   * @return a [Source] representing the file to which given URI was resolved
+   */
+  Source resolveAbsolute(Uri uri);
+
+  /**
+   * Return an absolute URI that represents the given source, or `null` if a valid URI cannot
+   * be computed.
+   *
+   * @param source the source to get URI for
+   * @return the absolute URI representing the given source
+   */
+  Uri restoreAbsolute(Source source) => null;
+}