org.overturetool.vdmj.syntax
Class SyntaxReader

java.lang.Object
  org.overturetool.vdmj.syntax.SyntaxReader

Direct Known Subclasses:

BindReader, ClassReader, DefinitionReader, ExpressionReader, ModuleReader, OvertureReader, PatternReader, StatementReader, TypeReader

public abstract class SyntaxReader
extends java.lang.Object

The parent class of all syntax readers.

Field Summary

protected BindReader	bindReader A BindReader, if created.
protected ClassReader	classReader A ClassReader, if created.
protected DefinitionReader	definitionReader A DefinitionReader, if created.
protected Dialect	dialect The dialect of VDM that we're parsing.
protected ExpressionReader	expressionReader An ExpressionReader, if created.
protected PatternReader	patternReader A PatternReader, if created.
protected LexTokenReader	reader The lexical analyser.
protected StatementReader	statementReader A StatementReader, if created.
protected TypeReader	typeReader A TypeReader, if created.

Constructor Summary

protected	SyntaxReader()
protected	SyntaxReader(LexTokenReader reader) Create a reader with the given lexical analyser and VDM++ flag.

Method Summary

protected void	checkFor(Token tok, int number, java.lang.String message) If the last token is as expected, advance, else raise an error.
void	close()
protected BindReader	getBindReader()
protected ClassReader	getClassReader()
java.lang.String	getCurrentModule()
protected DefinitionReader	getDefinitionReader()
int	getErrorCount()
java.util.List<VDMError>	getErrors()
protected ExpressionReader	getExpressionReader()
protected PatternReader	getPatternReader()
protected StatementReader	getStatementReader()
protected TypeReader	getTypeReader()
int	getWarningCount()
java.util.List<VDMWarning>	getWarnings()
protected LexNameToken	idToName(LexIdentifierToken id) Convert an identifier into a name.
protected boolean	ignore(Token tok) If the last token is the one passed, advance by one, else do nothing.
protected LexIdentifierToken	lastIdToken() Return the last token, converted to a LexIdentifierToken.
protected LexNameToken	lastNameToken() Return the last token, converted to a LexNameToken.
protected LexToken	lastToken() Return the last token read by the lexical analyser without advancing.
protected LexToken	nextToken() Read the next token from the lexical analyser, and advance by one token.
void	printErrors(java.io.PrintWriter out) Print errors and warnings to the PrintWriter passed.
void	printWarnings(java.io.PrintWriter out)
protected LexIdentifierToken	readIdToken(java.lang.String message) Return the last token as an identifier, and advance by one token.
protected LexNameToken	readNameToken(java.lang.String message) Return the last token as a name, and advance by one token.
protected LexToken	readToken() Return the last token read, and also advance by one token.
protected void	report(LocatedException error, Token[] after, Token[] upto) Raise a syntax error and attempt to recover.
void	setCurrentModule(java.lang.String module) Set the name of the current module or class.
protected void	throwMessage(int number, java.lang.String message) Raise a ParserException at the current location.
protected void	throwMessage(int number, java.lang.String message, LexToken token) Raise a ParserException at the location of the token passed in.
java.lang.String	toString()
protected void	warning(int no, java.lang.String msg, LexLocation location) Report a warning.

Methods inherited from class java.lang.Object

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

Field Detail

reader

protected final LexTokenReader reader

The lexical analyser.

dialect

protected final Dialect dialect

The dialect of VDM that we're parsing.

definitionReader

protected DefinitionReader definitionReader

A DefinitionReader, if created.

expressionReader

protected ExpressionReader expressionReader

An ExpressionReader, if created.

patternReader

protected PatternReader patternReader

A PatternReader, if created.

typeReader

protected TypeReader typeReader

A TypeReader, if created.

bindReader

protected BindReader bindReader

A BindReader, if created.

statementReader

protected StatementReader statementReader

A StatementReader, if created.

classReader

protected ClassReader classReader

A ClassReader, if created.

Constructor Detail

SyntaxReader

protected SyntaxReader(LexTokenReader reader)

Create a reader with the given lexical analyser and VDM++ flag.

SyntaxReader

protected SyntaxReader()

Method Detail

nextToken

protected LexToken nextToken()
                      throws LexException

Read the next token from the lexical analyser, and advance by one token.

Returns:

The next token.

Throws:

LexException

lastToken

protected LexToken lastToken()
                      throws LexException

Return the last token read by the lexical analyser without advancing. Repeated calls to this method will return the same result.

Returns:

The last token again.

Throws:

LexException

readToken

protected LexToken readToken()
                      throws LexException

Return the last token read, and also advance by one token. This is equivalent to calling lastToken() followed by nextToken(), but returning the result of lastToken.

Returns:

The last token.

Throws:

LexException

setCurrentModule

public void setCurrentModule(java.lang.String module)

Set the name of the current module or class. Unqualified symbol names use this as their module/class name. See idToName(org.overturetool.vdmj.lex.LexIdentifierToken).

Parameters:

module -

getCurrentModule

public java.lang.String getCurrentModule()

Returns:

The current module/class name.

idToName

protected LexNameToken idToName(LexIdentifierToken id)

Convert an identifier into a name. A name is an identifier that has a module name qualifier, so this method uses the current module to convert the identifier passed in.

Parameters:

id - The identifier to convert

Returns:

The corresponding name.

lastIdToken

protected LexIdentifierToken lastIdToken()
                                  throws ParserException,
                                         LexException

Return the last token, converted to a LexIdentifierToken. If the last token is not an identifier token, an exception is thrown with the message passed in.

Returns:

The last token as a LexIdentifierToken.

Throws:

LexException

ParserException

lastNameToken

protected LexNameToken lastNameToken()
                              throws LexException,
                                     ParserException

Return the last token, converted to a LexNameToken. If the last token is not a name token, or an identifier token that can be converted to a name, an exception is thrown with the message passed in.

Returns:

The last token as a LexIdentifierToken.

Throws:

LexException

ParserException

readIdToken

protected LexIdentifierToken readIdToken(java.lang.String message)
                                  throws LexException,
                                         ParserException

Return the last token as an identifier, and advance by one token. This is similar to calling lastIdToken() followed by nextToken, and returning the result of the lastIdToken.

Parameters:

message - The message to throw if the last token is not an id.

Returns:

The last token as a LexIdentifierToken.

Throws:

LexException

ParserException

readNameToken

protected LexNameToken readNameToken(java.lang.String message)
                              throws LexException,
                                     ParserException

Return the last token as a name, and advance by one token. This is similar to calling lastNameToken() followed by nextToken, and returning the result of the lastNameToken.

Parameters:

message - The message to throw if the last token is not a name.

Returns:

The last token as a LexNameToken.

Throws:

LexException

ParserException

getDefinitionReader

protected DefinitionReader getDefinitionReader()

Returns:

A new DefinitionReader.

getExpressionReader

protected ExpressionReader getExpressionReader()

Returns:

A new DefinitionReader.

getPatternReader

protected PatternReader getPatternReader()

Returns:

A new PatternReader.

getTypeReader

protected TypeReader getTypeReader()

Returns:

A new TypeReader.

getBindReader

protected BindReader getBindReader()

Returns:

A new BindReader.

getStatementReader

protected StatementReader getStatementReader()

Returns:

A new StatementReader.

getClassReader

protected ClassReader getClassReader()

Returns:

A new ClassReader.

close

public void close()
           throws java.io.IOException

Throws:

java.io.IOException

checkFor

protected void checkFor(Token tok,
                        int number,
                        java.lang.String message)
                 throws LexException,
                        ParserException

If the last token is as expected, advance, else raise an error.

Parameters:

tok - The token type to check for.

number - The error number.

message - The error message to raise if the token is not as expected.

Throws:

LexException

ParserException

ignore

protected boolean ignore(Token tok)
                  throws LexException

If the last token is the one passed, advance by one, else do nothing.

Parameters:

tok - The token type to check for.

Returns:

True if the token was skipped.

Throws:

LexException

throwMessage

protected void throwMessage(int number,
                            java.lang.String message)
                     throws ParserException,
                            LexException

Raise a ParserException at the current location.

Parameters:

number - The error number.

message - The error message.

Throws:

ParserException

LexException

throwMessage

protected void throwMessage(int number,
                            java.lang.String message,
                            LexToken token)
                     throws ParserException

Raise a ParserException at the location of the token passed in.

Parameters:

number - The error number.

message - The error message.

token - The location of the error.

Throws:

ParserException

report

protected void report(LocatedException error,
                      Token[] after,
                      Token[] upto)

Raise a syntax error and attempt to recover. The error is added to the errors list, and if this exceeds 100 errors the parser is aborted. The "after" and "upto" lists of token types are then used to control the advance of the parser to skip beyond the error. Tokens are read until one occurs in either list or EOF is reached. If the token is in the "after" list, one more token is read before returning; if it is in the "upto" list, the last token is left pointing to the token before returning. If EOF is reached, the method returns.

Parameters:

error - The exception that caused the error.

after - A list of tokens to recover to, and step one beyond.

upto - A list of tokens to recover to.

warning

protected void warning(int no,
                       java.lang.String msg,
                       LexLocation location)

Report a warning. Unlike errors, this does no token recovery.

getErrorCount

public int getErrorCount()

Returns:

The error count from all readers that can raise errors.

getErrors

public java.util.List<VDMError> getErrors()

Returns:

The errors from all readers that can raise errors.

getWarningCount

public int getWarningCount()

Returns:

The warning count from all readers that can raise warnings.

getWarnings

public java.util.List<VDMWarning> getWarnings()

Returns:

The warnings from all readers that can raise warnings.

printErrors

public void printErrors(java.io.PrintWriter out)

Print errors and warnings to the PrintWriter passed.

printWarnings

public void printWarnings(java.io.PrintWriter out)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object