org.codehaus.janino

Class Scanner

java.lang.Object

org.codehaus.janino.Scanner

public class Scanner
extends Object

Splits up a character stream into tokens and returns them as String objects.

The optionalFileName parameter passed to many constructors should point

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	Scanner.EOFToken
class	Scanner.IdentifierToken
class	Scanner.KeywordToken
class	Scanner.LiteralToken The type of the value parameter determines the type of the literal token: Type/value returned by Scanner.LiteralToken.getLiteralValue()Literal StringSTRING literal CharacterCHAR literal IntegerINT literal LongLONG literal FloatFLOAT literal DoubleDOUBLE literal BooleanBOOLEAN literal nullNULL literal
class	Scanner.Token

Field Summary

Fields

Modifier and Type	Field and Description
static Integer	MAGIC_INTEGER This reference represents the "magic" literal "2147483648" which is only allowed in a negated context.
static Long	MAGIC_LONG This reference represents the "magic" literal "9223372036854775808L" which is only allowed in a negated context.

Constructor Summary

Constructors

Constructor and Description
Scanner(File file) Deprecated.
Scanner(File file, String optionalEncoding) Deprecated.
Scanner(String fileName) Deprecated.
Scanner(String optionalFileName, InputStream is) Set up a scanner that reads tokens from the given InputStream in the platform default encoding.
Scanner(String optionalFileName, InputStream is, String optionalEncoding) Set up a scanner that reads tokens from the given InputStream with the given optionalEncoding (null means platform default encoding).
Scanner(String optionalFileName, Reader in) Set up a scanner that reads tokens from the given Reader.
Scanner(String optionalFileName, Reader in, short initialLineNumber, short initialColumnNumber) Creates a Scanner that counts lines and columns from non-default initial values.
Scanner(String fileName, String encoding) Deprecated.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Deprecated.
String	doc() Get the text of the doc comment (a.k.a.
String	getFileName() Return the file name optionally passed to the constructor.
static String	literalValueToString(Object v)
Location	location() Returns the Location of the next token.
Scanner.Token	peek() Peek the next token, but don't remove it from the input.
Scanner.Token	peekNextButOne() Peek the next but one token, neither remove the next nor the next but one token from the input.
Scanner.Token	read() Read the next token from the input.
void	setWarningHandler(WarningHandler optionalWarningHandler) By default, warnings are discarded, but an application my install a WarningHandler.

Methods inherited from class java.lang.Object

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

Field Detail

MAGIC_INTEGER

public static final Integer MAGIC_INTEGER

This reference represents the "magic" literal "2147483648" which is only allowed in a negated context.

MAGIC_LONG

public static final Long MAGIC_LONG

This reference represents the "magic" literal "9223372036854775808L" which is only allowed in a negated context.

Constructor Detail

Scanner

public Scanner(String fileName)
        throws CompileException,
               IOException

Deprecated.

Set up a scanner that reads tokens from the given file in the default charset.

This method is deprecated because it leaves the input file open.

Throws:

CompileException

IOException

Scanner

public Scanner(String fileName,
       String encoding)
        throws CompileException,
               IOException

Deprecated.

Set up a scanner that reads tokens from the given file in the given encoding.

This method is deprecated because it leaves the input file open.

Throws:

CompileException

IOException

Scanner

public Scanner(File file)
        throws CompileException,
               IOException

Deprecated.

Set up a scanner that reads tokens from the given file in the platform default encoding.

This method is deprecated because it leaves the input file open.

Throws:

CompileException

IOException

Scanner

public Scanner(File file,
       String optionalEncoding)
        throws CompileException,
               IOException

Deprecated.

Set up a scanner that reads tokens from the given file in the given encoding.

This method is deprecated because it leaves the input file open.

Throws:

CompileException

IOException

Scanner

public Scanner(String optionalFileName,
       InputStream is)
        throws CompileException,
               IOException

Set up a scanner that reads tokens from the given InputStream in the platform default encoding.

The fileName is solely used for reporting in thrown exceptions.

Throws:

CompileException

IOException

Scanner

public Scanner(String optionalFileName,
       InputStream is,
       String optionalEncoding)
        throws CompileException,
               IOException

Set up a scanner that reads tokens from the given InputStream with the given optionalEncoding (null means platform default encoding).

The optionalFileName is used for reporting errors during compilation and for source level debugging, and should name an existing file. If null is passed, and the system property org.codehaus.janino.source_debugging.enable is set to "true", then a temporary file in org.codehaus.janino.source_debugging.dir or the system's default temp dir is created in order to make the source code available to a debugger.

Throws:

CompileException

IOException

Scanner

public Scanner(String optionalFileName,
       Reader in)
        throws CompileException,
               IOException

Set up a scanner that reads tokens from the given Reader.

The optionalFileName is used for reporting errors during compilation and for source level debugging, and should name an existing file. If null is passed, and the system property org.codehaus.janino.source_debugging.enable is set to "true", then a temporary file in org.codehaus.janino.source_debugging.dir or the system's default temp dir is created in order to make the source code available to a debugger.

Throws:

CompileException

IOException

Scanner

public Scanner(String optionalFileName,
       Reader in,
       short initialLineNumber,
       short initialColumnNumber)
        throws CompileException,
               IOException

Creates a Scanner that counts lines and columns from non-default initial values.

Throws:

CompileException

IOException

Method Detail

getFileName

public String getFileName()

Return the file name optionally passed to the constructor.

close

public void close()
           throws IOException

Deprecated.

Closes the character source (file, InputStream, Reader) associated with this object. The results of future calls to peek() and read() are undefined.

This method is deprecated, because the concept described above is confusing. An application should close the underlying InputStream or Reader itself.

Throws:

IOException

read

public Scanner.Token read()
                   throws CompileException,
                          IOException

Read the next token from the input.

Throws:

CompileException

IOException

peek

public Scanner.Token peek()

Peek the next token, but don't remove it from the input.

peekNextButOne

public Scanner.Token peekNextButOne()
                             throws CompileException,
                                    IOException

Peek the next but one token, neither remove the next nor the next but one token from the input.

This makes parsing so much easier, e.g. for class literals like Map.class.

Throws:

CompileException

IOException

doc

public String doc()

Get the text of the doc comment (a.k.a. "JAVADOC comment") preceeding the next token.

Returns:

null if the next token is not preceeded by a doc comment

location

public Location location()

Returns the Location of the next token.

literalValueToString

public static String literalValueToString(Object v)

setWarningHandler

public void setWarningHandler(WarningHandler optionalWarningHandler)

By default, warnings are discarded, but an application my install a WarningHandler.

Notice that there is no Scanner.setErrorHandler() method, but scan errors always throw a CompileException. The reason being is that there is no reasonable way to recover from scan errors and continue scanning, so there is no need to install a custom scan error handler.

Parameters:

optionalWarningHandler - null to indicate that no warnings be issued