com.espertech.esper.epl.parse
Class ParseHelper

java.lang.Object
  com.espertech.esper.epl.parse.ParseHelper

public class ParseHelper
extends java.lang.Object

Helper class for parsing an expression and walking a parse tree.

Field Summary

static java.lang.String

newline Newline.

Constructor Summary

ParseHelper()

Method Summary

static boolean	hasControlCharacters(java.lang.String text)
static EsperEPL2GrammarLexer	newLexer(org.antlr.v4.runtime.CharStream input)
static EsperEPL2GrammarParser	newParser(org.antlr.v4.runtime.CommonTokenStream tokens)
static ParseResult	parse(java.lang.String expression, java.lang.String eplStatementErrorMsg, boolean addPleaseCheck, ParseRuleSelector parseRuleSelector, boolean rewriteScript) Parse expression using the rule the ParseRuleSelector instance supplies.
static void	walk(org.antlr.v4.runtime.tree.Tree ast, EPLTreeWalkerListener listener, java.lang.String expression, java.lang.String eplStatementForErrorMsg) Walk parse tree starting at the rule the walkRuleSelector supplies.

Methods inherited from class java.lang.Object

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

Field Detail

newline

public static final java.lang.String newline

Newline.

Constructor Detail

ParseHelper

public ParseHelper()

Method Detail

walk

public static void walk(org.antlr.v4.runtime.tree.Tree ast,
                        EPLTreeWalkerListener listener,
                        java.lang.String expression,
                        java.lang.String eplStatementForErrorMsg)

Walk parse tree starting at the rule the walkRuleSelector supplies.

Parameters:

ast - - ast to walk

listener - - walker instance

expression - - the expression we are walking in string form

eplStatementForErrorMsg - - statement text for error messages

parse

public static ParseResult parse(java.lang.String expression,
                                java.lang.String eplStatementErrorMsg,
                                boolean addPleaseCheck,
                                ParseRuleSelector parseRuleSelector,
                                boolean rewriteScript)
                         throws EPException

Parse expression using the rule the ParseRuleSelector instance supplies.

Parameters:

expression - - text to parse

parseRuleSelector - - parse rule to select

addPleaseCheck - - true to include depth paraphrase

eplStatementErrorMsg - - text for error

Returns:

AST - syntax tree

Throws:

EPException - when the AST could not be parsed

newLexer

public static EsperEPL2GrammarLexer newLexer(org.antlr.v4.runtime.CharStream input)

newParser

public static EsperEPL2GrammarParser newParser(org.antlr.v4.runtime.CommonTokenStream tokens)

hasControlCharacters

public static boolean hasControlCharacters(java.lang.String text)