org.apache.cocoon.components.language.markup.xsp
Class XSPExpressionParser

java.lang.Object
  org.apache.cocoon.components.language.markup.xsp.XSPExpressionParser

public class XSPExpressionParser
extends Object

Parse XSP expressions. Expressions are embedded in attribute="value" and text elements and are expanded by the PreProcessFilter and have the form {#expression}. To prevent interpolation, use {##quote}, which results in the text {#quote}. An exception is thrown if the closing brace is missing.

The parser has a rudimentary understanding of expressions concerning nested braces and braces inside quoted strings and character constants. All valid Java, Javascript, and Python expressions can be used.

Example: <h1>Hello {#user.getName()}</h1> <img or src="image_{#image.getId()}"/>

Version:

SVN $Id: XSPExpressionParser.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Nested Class Summary

static interface	XSPExpressionParser.Handler Handler interface for parsed expressions and text fragments.
protected static class	XSPExpressionParser.QuotedState Parser state in a quoted string.
protected static class	XSPExpressionParser.State Parser state.

Field Summary

protected static XSPExpressionParser.State	EXPRESSION_CHAR_STATE The parser has encountered '\'' in EXPRESSION_STATE to start a character constant.
protected static XSPExpressionParser.State	EXPRESSION_SHELL_STATE The parser has encountered '`' (Backtick, ASCII 0x60) in EXPRESSION_STATE to start a Python string constant.
protected static XSPExpressionParser.State	EXPRESSION_STATE The parser is parsing an expression.
protected static XSPExpressionParser.State	EXPRESSION_STRING_STATE The parser has encountered '"' in EXPRESSION_STATE to start a string constant.
protected static XSPExpressionParser.State	LBRACE_STATE The parser has encountered '{' in TEXT_STATE.
protected static XSPExpressionParser.State	TEXT_HASH_STATE The parser has encountered '#' in LBRACE_STATE.
protected static XSPExpressionParser.State	TEXT_STATE The parser is parsing text.

Constructor Summary

XSPExpressionParser(XSPExpressionParser.Handler handler)
Create a new XSPExpressionParser.

Method Summary

protected void	append(char ch)
void	consume(char[] chars, int start, int length) Parses part of a character array.
void	consume(String chars) Parses a character sequence.
protected int	decrNesting()
void	flush(Locator locator, String description) Flushes the parser
protected String	getExpression()
protected XSPExpressionParser.State	getState()
protected void	handleExpression()
protected void	handleText()
protected void	incrNesting()
protected void	initExpression()
protected boolean	isEscaped()
protected void	setEscaped(boolean escaped)
protected void	setState(XSPExpressionParser.State state)

Methods inherited from class java.lang.Object

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

Field Detail

TEXT_STATE

protected static final XSPExpressionParser.State TEXT_STATE

The parser is parsing text.

LBRACE_STATE

protected static final XSPExpressionParser.State LBRACE_STATE

The parser has encountered '{' in TEXT_STATE.

TEXT_HASH_STATE

protected static final XSPExpressionParser.State TEXT_HASH_STATE

The parser has encountered '#' in LBRACE_STATE.

EXPRESSION_STATE

protected static final XSPExpressionParser.State EXPRESSION_STATE

The parser is parsing an expression.

EXPRESSION_STRING_STATE

protected static final XSPExpressionParser.State EXPRESSION_STRING_STATE

The parser has encountered '"' in EXPRESSION_STATE to start a string constant.

EXPRESSION_CHAR_STATE

protected static final XSPExpressionParser.State EXPRESSION_CHAR_STATE

The parser has encountered '\'' in EXPRESSION_STATE to start a character constant.

EXPRESSION_SHELL_STATE

protected static final XSPExpressionParser.State EXPRESSION_SHELL_STATE

The parser has encountered '`' (Backtick, ASCII 0x60) in EXPRESSION_STATE to start a Python string constant.

Constructor Detail

XSPExpressionParser

public XSPExpressionParser(XSPExpressionParser.Handler handler)

Create a new XSPExpressionParser.

Parameters:

handler - The handler for parsed text and expression fragments.

Method Detail

consume

public void consume(String chars)
             throws SAXException

Parses a character sequence.

Parameters:

chars - The character sequence to parse

Throws:

SAXException - If there is an error in the sequence.

consume

public void consume(char[] chars,
                    int start,
                    int length)
             throws SAXException

Parses part of a character array.

Parameters:

chars - The characters

start - The start position in the character array

length - The number of characters to parse

Throws:

SAXException - If there is an error in the sequence.

flush

public void flush(Locator locator,
                  String description)
           throws SAXException

Flushes the parser

Parameters:

locator - The SAX locator to determine the current parse position

description - The description of the current parse context

Throws:

SAXException - If there is an error in the parsed text. A wrapped LocatedException contains the location of the parse error.

getState

protected XSPExpressionParser.State getState()

setState

protected void setState(XSPExpressionParser.State state)

initExpression

protected void initExpression()

incrNesting

protected void incrNesting()

decrNesting

protected int decrNesting()

setEscaped

protected void setEscaped(boolean escaped)

isEscaped

protected boolean isEscaped()

getExpression

protected String getExpression()

handleText

protected void handleText()
                   throws SAXException

Throws:

SAXException

handleExpression

protected void handleExpression()
                         throws SAXException

Throws:

SAXException

append

protected void append(char ch)