org.codehaus.janino

Class Scanner

java.lang.Object

org.codehaus.janino.Scanner

public class Scanner
extends java.lang.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.Token Representation of a Java™ token.

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	crLfPending
private java.lang.String	docComment The optional JAVADOC comment preceding the #nextToken.
private boolean	expectGreater Whether the scanner is in 'expect greater' mode: If so, it parses character sequences like ">>>=" as ">", ">", ">", "=".
private java.io.Reader	in
private static java.util.Map<java.lang.String,java.lang.String>	JAVA_KEYWORDS
private static java.util.Map<java.lang.String,java.lang.String>	JAVA_OPERATORS
private static java.util.Map<java.lang.String,java.lang.String>	JAVA_OPERATORS_EXPECT_GREATER
private int	nextChar
private short	nextCharColumnNumber
private short	nextCharLineNumber
private java.lang.String	optionalFileName
private WarningHandler	optionalWarningHandler
private short	tokenColumnNumber Column number of the first character of the previously produced token (1 if token is immediately preceded by a line break).
private short	tokenLineNumber Line number of the previously produced token (typically starting at one).

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method and Description
void	close() Deprecated. This method is deprecated, because the concept described above is confusing. An application should close the underlying InputStream or Reader itself.
java.lang.String	doc() Get the text of the doc comment (a.k.a.
boolean	getExpectGreater()
java.lang.String	getFileName()
Location	location()
Scanner.Token	produce() Preduces and returns the next token.
private void	readNextChar()
private void	scanLiteralCharacter(java.lang.StringBuilder sb) Scans the next literal character into a StringBuilder.
private Scanner.Token	scanNumericLiteral(boolean hadDecimalPoint)
boolean	setExpectGreater(boolean value) Sets or resets the 'expect greater' mode.
void	setWarningHandler(WarningHandler optionalWarningHandler) By default, warnings are discarded, but an application my install a WarningHandler.
private void	warning(java.lang.String handle, java.lang.String message, Location optionalLocation) Issues a warning with the given message and location and returns.

Methods inherited from class java.lang.Object

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

Field Detail

optionalFileName

private final java.lang.String optionalFileName

in

private final java.io.Reader in

nextChar

private int nextChar

crLfPending

private boolean crLfPending

nextCharLineNumber

private short nextCharLineNumber

nextCharColumnNumber

private short nextCharColumnNumber

tokenLineNumber

private short tokenLineNumber

Line number of the previously produced token (typically starting at one).

tokenColumnNumber

private short tokenColumnNumber

Column number of the first character of the previously produced token (1 if token is immediately preceded by a line break).

docComment

private java.lang.String docComment

The optional JAVADOC comment preceding the #nextToken.

expectGreater

private boolean expectGreater

Whether the scanner is in 'expect greater' mode: If so, it parses character sequences like ">>>=" as ">", ">", ">", "=".

JAVA_KEYWORDS

private static final java.util.Map<java.lang.String,java.lang.String> JAVA_KEYWORDS

JAVA_OPERATORS

private static final java.util.Map<java.lang.String,java.lang.String> JAVA_OPERATORS

JAVA_OPERATORS_EXPECT_GREATER

private static final java.util.Map<java.lang.String,java.lang.String> JAVA_OPERATORS_EXPECT_GREATER

optionalWarningHandler

private WarningHandler optionalWarningHandler

Constructor Detail

Scanner

@Deprecated
public Scanner(java.lang.String fileName)
                    throws CompileException,
                           java.io.IOException

Deprecated. // SUPPRESS CHECKSTYLE MissingDeprecated

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

java.io.IOException

Scanner

@Deprecated
public Scanner(java.lang.String fileName,
                           java.lang.String encoding)
                    throws CompileException,
                           java.io.IOException

Deprecated. // SUPPRESS CHECKSTYLE MissingDeprecated

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

java.io.IOException

Scanner

@Deprecated
public Scanner(java.io.File file)
                    throws CompileException,
                           java.io.IOException

Deprecated. // SUPPRESS CHECKSTYLE MissingDeprecated

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

java.io.IOException

Scanner

@Deprecated
public Scanner(java.io.File file,
                           java.lang.String optionalEncoding)
                    throws CompileException,
                           java.io.IOException

Deprecated. // SUPPRESS CHECKSTYLE MissingDeprecated

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

java.io.IOException

Scanner

public Scanner(java.lang.String optionalFileName,
               java.io.InputStream is)
        throws CompileException,
               java.io.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

java.io.IOException

Scanner

public Scanner(java.lang.String optionalFileName,
               java.io.InputStream is,
               java.lang.String optionalEncoding)
        throws CompileException,
               java.io.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

java.io.IOException

Scanner

public Scanner(java.lang.String optionalFileName,
               java.io.Reader in)
        throws CompileException,
               java.io.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

java.io.IOException

Scanner

public Scanner(java.lang.String optionalFileName,
               java.io.Reader in,
               short initialLineNumber,
               short initialColumnNumber)
        throws CompileException,
               java.io.IOException

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

Throws:

CompileException

java.io.IOException

Method Detail

getFileName

public java.lang.String getFileName()

Returns:

The file name optionally passed to the constructor

close

@Deprecated
public void close()
                       throws java.io.IOException

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

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

Throws:

java.io.IOException

doc

public java.lang.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 character

produce

public Scanner.Token produce()
                      throws CompileException,
                             java.io.IOException

Preduces and returns the next token. Notice that end-of-input is not signalized with a null product, but by the special Scanner.Token.EOF token.

Throws:

CompileException

java.io.IOException

getExpectGreater

public boolean getExpectGreater()

Returns:

Whether the scanner is currently in 'expect greater' mode

setExpectGreater

public boolean setExpectGreater(boolean value)

Sets or resets the 'expect greater' mode.

Returns:

Whether the 'expect greater' mode was previously active

scanNumericLiteral

private Scanner.Token scanNumericLiteral(boolean hadDecimalPoint)
                                  throws CompileException,
                                         java.io.IOException

Throws:

CompileException

java.io.IOException

scanLiteralCharacter

private void scanLiteralCharacter(java.lang.StringBuilder sb)
                           throws CompileException,
                                  java.io.IOException

Scans the next literal character into a StringBuilder.

Throws:

CompileException

java.io.IOException

readNextChar

private void readNextChar()
                   throws java.io.IOException,
                          CompileException

Throws:

java.io.IOException

CompileException

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

warning

private void warning(java.lang.String handle,
                     java.lang.String message,
                     Location optionalLocation)
              throws CompileException

Issues a warning with the given message and location and returns. This is done through a WarningHandler that was installed through setWarningHandler(WarningHandler).

The handle argument qulifies the warning and is typically used by the WarningHandler to suppress individual warnings.

Throws:

CompileException