Text Schema Object Model classes

The Text Schema Object Model (TextSOM) is API that allows you to create, edit, and validate schemas programmatically.
Text Schema is a collection of objects that could be compiled, verified, saved, loaded and used together to parse and validate text documents.
Every class in SOM have its own ToString() method overridden which should be used to re-create schema text from its internal representation. This allows to inspect all optimization performed during schema compilation.

Class TextSchemaObject
public class TextSchemaObject

Represents the root class for the SOM hierarchy.
Property Type Description
Parent TextSchemaGroup, get/set The parent group of this TextSchemaObject.
Type TextItemType, get Type of this TextSchemaObject.
Flagged bool, get True if one of Flags (Optional, ZeroPlus, OnePlus) is set.
Optional bool, get/set Get/Set Optional (?) status of this TextSchemaObject.
OnePlus bool, get/set Get/Set OnePlus (+) status of this TextSchemaObject.
ZeroPlus bool, get/set Get/Set ZeroPlus (*) status of this TextSchemaObject.
Method Parameters Description
SetFlagsFrom TextSchemaObject, returns void Set flags from given TextSchemaObject.
UpdateFlagsFrom TextSchemaObject, returns void Update/Merge flags from given TextSchemaObject. For example, '+' and '?' will be '*'.

Class TextSchemaString
public class TextSchemaString : TextSchemaObject

This class represents a fixed string in a schema.
Constructor Parameters Description
TextSchemaString None Default constructor. Initialized as empty string.
Property Type Description
Name string, get/set Content of string.
CaseSensitive bool, get/set Case seisitivity to compare within a document.
Method Parameters Description
ToString returns void Textual representation of object.

Class TextSchemaChar
public class TextSchemaChar : TextSchemaObject

This class represents a character class in a schema.
Constructor Parameters Description
TextSchemaChar None Default constructor. Initializes char with empty specification.
Property Type Description
Restrictions string, get/set Specification of character class, in string form.
Negative bool, get/set Make character class inverted.
Method Parameters Description
Compile returns bool Compile textual specification to internal form. If failed, returns false.
ToString returns void Textual representation of object.

Class TextSchemaRuleRef
public class TextSchemaRuleRef : TextSchemaObject

This class represents a reference to rule in a schema.
Constructor Parameters Description
TextSchemaRuleRef None Default constructor.
TextSchemaRuleRef TextSchemaRule Initializes reference to a given rule.
Property Type Description
Name string, get/set Name of referenced rule.
TextInclude bool, get/set If true, schema parser will replace this rule ref to its content in rule definition.
Rule TextSchemaRule, get/set Referenced rule.
Method Parameters Description
ToString returns void Textual representation of object.

Class TextSchemaGroup
public class TextSchemaGroup : TextSchemaObject

This class represents a group (sequential or enumeration) in a schema.
Constructor Parameters Description
TextSchemaGroup None Default constructor. Creates an empty sequential group.
TextSchemaGroup IEnumerable<TextSchemaObject> Creates a sequential group filled with list members.
Property Type Description
Items List<TextSchemaObject>, get Internal list of itmes. It is not recommended to manipulate text schema objects using this List members directly. Instead, use special methods of TextSchemaGroup.
Sequential bool, get/set If true, group is sequential, if false - enumeration.
Method Parameters Description
Reparent returns void Set parent value of list members to this TextSchemaGroup. May be used to correct parent values if list members were inserted with list methods.
AddItem TextSchemaObject, returns void Append element to the list.
InsertItem int idx, TextSchemaObject obj, returns void Insert element to the list, to position specified by idx.
AddRange IEnumerable<TextSchemaObject>, returns void Append elements to the list.
InsertRange int idx, IEnumerable<TextSchemaObject> objs, returns void Insert elements to the list, to position specified by idx.
RemoveItem in idx, returns void Remove element from the list at position idx.
ReplaceItem int idx, TextSchemaObject obj, returns void Replace element in the list at position idx, to object obj.
ToString returns void Textual representation of object.

Class TextSchemaRule
public class TextSchemaRule

This class represents a rule in a schema.
Constructor Parameters Description
TextSchemaRule None Default constructor. Creates empty rule.
Property Type Description
RootGroup TextSchemaGroup, get only Returns always sequential group of elements representing content of the rule.
Items List<TextSchemaObject>, get only Items of the RootGroup.
Name string, get/set Name of the rule.
IsDocument bool, get True if this rule looks like document root. Set by schema parser.
IsTerminal bool, get True if this rule contains strings and characters only. Set by schema parser.
IsAllowEmpty bool, get True if this rule contains optional elements only. Set by schema parser.
IsPrivate bool, get True if this rule inherited from included file and should not be used as document (root rule). Set by schema parser.
IsOptimizedGroup bool, get True if this rule was optimized (groups reordering) by schema parser.
IsOptimizedCommonItem bool, get True if this rule was optimized (common items optimization) by schema parser.
IsOptimizedLeftRecursion bool, get True if this rule was optimized (left recursion elimination) by schema parser.
IsOptimizedIndirectLeftRecursion bool, get True if this rule was optimized (indirect left recursion elimination) by schema parser.
Method Parameters Description
ToString returns void Textual representation of object.

Class TextSchema
public class TextSchema

This class represents a text document schema which contains all rules and header options provided in the schema description.
TextSchema validates and compile schema.
Schema must be compiled and must be valid before use for documents parsing and validation.
Constructor Parameters Description
TextSchema None Default constructor.
TextSchema TextSchema Copy constructor.
Property Type Description
MimeTypes IEnumerable<string>, get only Returns set of mime types assigned to the current document with "mime_types" header field.
Extensions IEnumerable<string>, get only Returns set of extensions assigned to the current document with "extensions" header field.
StartRule TextSchemaRuleRef, get only Reference to a start document rule.
StartComments List<string>, get only List of allowed start comments literals.
EndComments List<string>, get only List of allowed end comments literals.
Credits string, get/set Represents a credits value from header information block.
Comments string, get/set Represents a comments value from header information block.
License string, get/set Represents a license value from header information block.
Version int, get/set Represents a version value from header information block.
IgnoreWhiteSpace bool, get/set Represents a IgnoreWhiteSpace value from header information block.
Rules List<TextSchemaRule>, get only Provides access to collection of rules.
Documents IEnumerable<TextSchemaRule>, get only Provides access to temporary collection of root rules, excluding ones marked as private.
IsCompiled bool, get only Indicates that the schema is compiled and verified.
IsValid bool, get only Indicates that the schema is valid.
Method Parameters Description
FindRule string name, returns TextSchemaRule Finds a rule by name in internal rules array. If not found, returns null.
SetMimeTypes string name, returns void Sets a string with mime types collection as a comma separated list.
SetExtensions string name, returns void Sets a string with extensions collection as a comma separated list.
SetStartRule string name, returns void Sets a name of start rule. Will be checked on compile stage.
Compile TextValidationEventHandler handler, returns void Compiles a schema and makes optimizations. On error, if handler == null, throws TextSchemaException.
static Read ITextSchemaReader reader, TextReader trd, TextValidationEventHandler han, returns BinSchema Parses a schema loaded from TextReader using ITextSchemaReader interface, compiles a schema and returns it. On error, calls BinValidationEventHandler.
static Load Stream dump, returns BinSchema Deserializes a schema and returns it.
Save Stream dump, returns void Serializes the schema.
ToString returns void Textual representation of object.

Class TextSchemaException
public class TextSchemaException : SystemException

This class contains exception details for exceptions thrown when TextSchema compiler and validator encounter an error.
Constructor Parameters Description
TextSchemaException TextSchemaObject obj Constructs an exception with source object.
TextSchemaException TextSchemaObject obj, string message Constructs an exception with a source object and a message.
TextSchemaException TextSchemaObject obj, string message, int line Constructs an exception with a source object, a message, and a line number.
TextSchemaException TextSchemaObject obj, string message, Exception e Constructs an exception with a source object, a message, and an inner exception.
Property Type Description
LineNumber int, get only Returns a line number of the error (in the bdd file). If the error cannot be linked to a specific line, returns -1.
SourceSchemaObject TextSchemaObject, get only Returns an object which caused the error.

Class TextSchemaInfo
public class TextSchemaInfo : ITextSchemaInfo

Provides schema information for validated text node.
Constructor Parameters Description
TextSchemaInfo None Default constructor. Creates empty schema info object.
TextSchemaInfo TextSchemaObject obj, bool isValid Initializes schema info object with provided values.

Class TextValidationEventArgs
public class TextValidationEventArgs : EventArgs

Encapsulates information about validation error/warning.
Constructor Parameters Description
TextValidationEventArgs TextSchemaException, SeverityType severity Initializes object with provided values.
Property Type Description
Exception TextSchemaException, get only Returns an exception information.
Severity SeverityType, get only Returns an severity of the error.

Interface ITextSchemaInfo
public interface ITextSchemaInfo

Provides an interface for current node schema information access.
Property Type Description
SchemaObject TextSchemaObject, get only Returns a schema object corresponding to the current node.
Validity bool, get only Returns true if schema information is valid (current node is validated successfully).

Interface ITextSchemaReader
public interface ITextSchemaReader

Defines an interface for schema parsers.
Any class that implements this interface and parses schema description in some format (C-like, XML, etc) and translates it into TextSchema object, could be used as an alternative schema parser.
Method Parameters Description
Parse TextReader trd, TextSchema schema, TextValidationEventHandler handler, returns void Reads schema description from TextReader, fills TextSchema and reports errors to handler if it is not null.

Enumeration TextItemType
public enum TextItemType

Provides information about type of text schema object.
Member Description
TI_TYPE_NONE TextSchemaObject object created by error, not a real text schema type.
TI_TYPE_STRING Fixed string
TI_TYPE_RULE Rule reference object
TI_TYPE_GROUP Group, sequential or enumeration
TI_TYPE_CHAR Character class

Enumeration TextItemFlags
public enum TextItemFlags

Represents flags of item in schema.
Member Description
TI_NONE No flags.
TI_OPTIONAL Item is optional (?)
TI_ZEROPLUS Item is zero or more (*)
TI_ONEPLUS Item is one or more (+)

Enumeration TextRuleFlags
public enum TextRuleFlags

Represents flags text rule in schema.
Member Description
TT_NONE No flags.
TT_ROOT Rule is potential root element
TT_PRIVATE Rule is from included file and cannot be root
TT_TERMINAL Rule contains characters and strings only and could be represented as a single string
TT_ALLOWEMPTY All rule members are optional

Delegate TextValidationEventHandler
public delegate void textValidationEventHandler(
Object sender,
TextValidationEventArgs e
);

Represents the callback method that will catch text schema validation events.

See also: