org.datanucleus.query.compiler

Class JDOQLParser

java.lang.Object

org.datanucleus.query.compiler.JDOQLParser

All Implemented Interfaces:

Parser

public class JDOQLParser
extends Object
implements Parser

Implementation of a parser for JDOQL query language. Generates Node tree(s) by use of the various parseXXX() methods.

Constructor Summary

Constructors

Constructor and Description
JDOQLParser(Map options) Constructor for a JDOQL Parser.

Method Summary

Modifier and Type	Method and Description
void	allowSingleEquals(boolean flag)
Node	parse(String expression)
Node[]	parseFrom(String expression)
Node[]	parseOrder(String expression)
Node[][]	parseParameters(String expression)
Node[]	parseResult(String expression) The RESULT expression in JDOQL can include aggregates, fields, as well as aliases myfield [AS] alias, myfield2" The Node tree for this would be
Node[]	parseTuple(String expression)
Node[]	parseUpdate(String expression)
Node	parseVariable(String expression)
Node[][]	parseVariables(String expression)
protected void	processAdditiveExpression()
protected boolean	processLiteral() A literal is one value of any type.
protected void	processMultiplicativeExpression()
protected void	processPrimary() Parses the primary.
protected void	processUnaryExpression()

Methods inherited from class java.lang.Object

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

Constructor Detail

JDOQLParser

public JDOQLParser(Map options)

Constructor for a JDOQL Parser. Supports "jdoql.level" option so can have strict JDO2 syntax, or flexible.

Parameters:

options - parser options

Method Detail

allowSingleEquals

public void allowSingleEquals(boolean flag)

parse

public Node parse(String expression)

Specified by:

parse in interface Parser

parseVariable

public Node parseVariable(String expression)

Specified by:

parseVariable in interface Parser

parseFrom

public Node[] parseFrom(String expression)

Specified by:

parseFrom in interface Parser

parseUpdate

public Node[] parseUpdate(String expression)

Specified by:

parseUpdate in interface Parser

parseOrder

public Node[] parseOrder(String expression)

Specified by:

parseOrder in interface Parser

parseResult

public Node[] parseResult(String expression)

The RESULT expression in JDOQL can include aggregates, fields, as well as aliases

• myfield [AS] alias, myfield2"

The Node tree for this would be

[
 [IDENTIFIER : myfield.
      [NAME : alias]],
 [IDENTIFIER : myfield2]
 ]

Specified by:

parseResult in interface Parser

Returns:

Node tree(s) for the RESULT expression

parseTuple

public Node[] parseTuple(String expression)

Specified by:

parseTuple in interface Parser

parseVariables

public Node[][] parseVariables(String expression)

Specified by:

parseVariables in interface Parser

parseParameters

public Node[][] parseParameters(String expression)

Specified by:

parseParameters in interface Parser

processAdditiveExpression

protected void processAdditiveExpression()

processMultiplicativeExpression

protected void processMultiplicativeExpression()

processUnaryExpression

protected void processUnaryExpression()

processPrimary

protected void processPrimary()

Parses the primary. First look for a literal (e.g. "text"), then an identifier(e.g. variable) In the next step, call a function, if executing a function, on the literal or the identifier found.

processLiteral

protected boolean processLiteral()

A literal is one value of any type. Supported literals are of types String, Floating Point, Integer, Character, Boolean and null e.g. 'J', "String", 1, 1.8, true, false, null.

Returns:

The parsed literal