net.oneandone.mork.mapping

Class Mapper

java.lang.Object

net.oneandone.mork.mapping.Mapper

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

MorkMapper

public class Mapper
extends Object
implements Serializable

Maps streams into Objects by scanning. Implements the analyzing parts a compiler or any other text processing program: scanner, parser and attribution. Mappers don't store symbol tables because they would only be necessary for visualization. Technically, a Mapper is a translated Mapping.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Mapper(String name) Creates a mapper with the specified name.
Mapper(String name, ErrorHandler errorHandler)
Mapper(String name, Parser parser, Oag oag) Create a mapper with the specified parser and semantics.
Mapper(String name, Parser parser, Oag oag, ErrorHandler errorHandler)

Method Summary

Modifier and Type	Method and Description
ErrorHandler	getErrorHandler()
Parser	getParser()
Oag	getSemantics()
boolean	isLoaded() Returns true if the mapper tables have already been loaded.
void	load() Loads the mapper tables if not already done so.
Mapper	newInstance() Creates a new mapper instance.
void	repl(String prompt, String end) Read-eval-print loop.
Object[]	run(File file)
Object[]	run(net.oneandone.sushi.fs.Node node)
Object[]	run(Position position, Reader src) Reads an stream, creates the syntax tree, computes the attributes and returns the attributes of the start symbol.
Object[]	run(String fileName)
Object[]	run(String context, Reader src)
void	setEnvironment(Object environment) Defines the environment object of the mapper.
void	setErrorHandler(ErrorHandler errorHandler) Defines the handler to report errors to.
void	setLogging(PrintWriter logParsing, PrintWriter logAttribution)
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Mapper

public Mapper(String name)

Creates a mapper with the specified name.

Mapper

public Mapper(String name,
              ErrorHandler errorHandler)

Mapper

public Mapper(String name,
              Parser parser,
              Oag oag)

Create a mapper with the specified parser and semantics. This constructor is used my Mork when generating a mapper, applications will usually use Mapper(String).

Mapper

public Mapper(String name,
              Parser parser,
              Oag oag,
              ErrorHandler errorHandler)

Method Detail

newInstance

public Mapper newInstance()

Creates a new mapper instance. Shares common data (esp. scanner and parser table with this instance.

load

public void load()

Loads the mapper tables if not already done so. This method is usually invoked implicity by the various run methods. Don't call load explicitly unless you want to force loading of mapper tables.

I tried to load the mapper from a background Thread started in the constructor. But the overall performance (of the jp example) was worse, probably because class loading is to fast (and out-performes the threading overhead).

Throws:

IllegalStateException - to indicate a class loading problem

isLoaded

public boolean isLoaded()

Returns true if the mapper tables have already been loaded.

getErrorHandler

public ErrorHandler getErrorHandler()

setErrorHandler

public void setErrorHandler(ErrorHandler errorHandler)

Defines the handler to report errors to.

Parameters:

errorHandler - may be null

setEnvironment

public void setEnvironment(Object environment)

Defines the environment object of the mapper. To access the environment object from your mapper file use YourSymbols : [env];. The default environment object is this.

Parameters:

environment - may be null

setLogging

public void setLogging(PrintWriter logParsing,
                       PrintWriter logAttribution)

getParser

public Parser getParser()

getSemantics

public Oag getSemantics()

run

public Object[] run(String fileName)
             throws IOException

Throws:

IOException

run

public Object[] run(net.oneandone.sushi.fs.Node node)
             throws IOException

Throws:

IOException

run

public Object[] run(File file)
             throws IOException

Throws:

IOException

run

public Object[] run(String context,
                    Reader src)
             throws IOException

Throws:

IOException

run

public Object[] run(Position position,
                    Reader src)
             throws IOException

Reads an stream, creates the syntax tree, computes the attributes and returns the attributes of the start symbol. Main functionality of this class, all other run methods use it. Reports errors to the registered errorHander; if there is no errorHandler defined, this method defines a PrintWriterErrorHandler for System.err.

Parameters:

src - when the method returns, src is always closed.

Returns:

never null

Throws:

IOException - to report errors

repl

public void repl(String prompt,
                 String end)

Read-eval-print loop. Loop terminates if the specified end string is entered. This method is handy to test mappers interactively. TODO: should print all attributes returned by the mapper, but currently, this would also print transport attributes.

Parameters:

prompt - prompt string.

end - string to terminal real-eval-print loop; null specifies that the loop will not be terminated.

toString

public String toString()

Overrides:

toString in class Object