ca.uqac.dim.turtledb

Class XmlQueryParser

java.lang.Object

ca.uqac.dim.turtledb.XmlQueryParser

public class XmlQueryParser
extends java.lang.Object

Facilities to build relational queries from an XML representation. The XmlQueryParser works in pair with the XmlQueryFormatter; more precisely, for any Relation r, we should have that XmlQueryParser.parse(XmlQueryFormatter.toXmlDocument(r)) == r

Author:

sylvain

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	XmlQueryParser.ParseException Exception raised when the parser wants to signal an error.

Constructor Summary

Constructors

Constructor and Description
XmlQueryParser()

Method Summary

Modifier and Type	Method and Description
static Relation	parse(org.w3c.dom.Document doc) Builds a query from a DOM document
protected static Relation	parse(org.w3c.dom.Node e) Parse an operand.
static Relation	parse(java.lang.String s) Builds a query from a string
protected static Attribute	parseAttribute(org.w3c.dom.Node e) Parse an attribute.
protected static Condition	parseCondition(org.w3c.dom.Node e) Parse an equality.
protected static Equality	parseEquality(org.w3c.dom.Node e) Parse an equality.
protected static Relation	parseIntersection(org.w3c.dom.Node e) Parse an intersection.
protected static Relation	parseJoin(org.w3c.dom.Node e) Parse a join.
protected static Condition	parseNAryCondition(NAryCondition c, org.w3c.dom.Node e)
protected static Relation	parseProduct(org.w3c.dom.Node e) Parse a Cartesian product.
protected static Relation	parseProjection(org.w3c.dom.Node e) Parse a projection.
protected static Schema	parseSchema(org.w3c.dom.Node e) Parse a schema.
protected static Relation	parseSelection(org.w3c.dom.Node e) Parse a selection.
protected static Table	parseTable(org.w3c.dom.Node e) Parse a table.
protected static Tuple	parseTuple(org.w3c.dom.Node e) Parse a table tuple.
protected static Relation	parseUnion(org.w3c.dom.Node e) Parse a union.
protected static Value	parseValue(org.w3c.dom.Node e) Parse a value.
protected static VariableTable	parseVariableTable(org.w3c.dom.Node e) Parse a table.

Methods inherited from class java.lang.Object

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

Constructor Detail

XmlQueryParser

public XmlQueryParser()

Method Detail

parse

public static Relation parse(java.lang.String s)
                      throws XmlQueryParser.ParseException

Builds a query from a string

Parameters:

s - A string containing an XML representation of the query

Returns:

The query

Throws:

XmlQueryParser.ParseException

parse

public static Relation parse(org.w3c.dom.Document doc)
                      throws XmlQueryParser.ParseException

Builds a query from a DOM document

Parameters:

s - A DOM document containing an XML representation of the query

Returns:

The query

Throws:

XmlQueryParser.ParseException

parse

protected static Relation parse(org.w3c.dom.Node e)
                         throws XmlQueryParser.ParseException

Parse an operand. XML syntax:

 <operand>
   <x>…</x>
 </operand>
 

where x is either intersection, union, selection, projection or table.

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseSelection

protected static Relation parseSelection(org.w3c.dom.Node e)
                                  throws XmlQueryParser.ParseException

Parse a selection. XML syntax:

 <projection>
   <condition>…</condition>
   <operand>…</operand>
 </projection>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseProjection

protected static Relation parseProjection(org.w3c.dom.Node e)
                                   throws XmlQueryParser.ParseException

Parse a projection. XML syntax:

 <projection>
   <schema>…</schema>
   <operand>…</operand>
 </projection>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseUnion

protected static Relation parseUnion(org.w3c.dom.Node e)
                              throws XmlQueryParser.ParseException

Parse a union. XML syntax:

 <union>
   <operand>…</operand>
   <operand>…</operand>
   …
 </union>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseIntersection

protected static Relation parseIntersection(org.w3c.dom.Node e)
                                     throws XmlQueryParser.ParseException

Parse an intersection. XML syntax:

 <intersection>
   <operand>…</operand>
   <operand>…</operand>
   …
 </intersection>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseProduct

protected static Relation parseProduct(org.w3c.dom.Node e)
                                throws XmlQueryParser.ParseException

Parse a Cartesian product. XML syntax:

 <product>
   <operand>…</operand>
   <operand>…</operand>
   …
 </product>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseJoin

protected static Relation parseJoin(org.w3c.dom.Node e)
                             throws XmlQueryParser.ParseException

Parse a join. XML syntax:

 <join>
   <condition>…</condition>
   <operand>…</operand>
   <operand>…</operand>
 </join>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseCondition

protected static Condition parseCondition(org.w3c.dom.Node e)
                                   throws XmlQueryParser.ParseException

Parse an equality. XML syntax:

 <condition>
   <x>…</x>
 </condition>
 

where x is equals (no other conditions implemented at the moment).

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseNAryCondition

protected static Condition parseNAryCondition(NAryCondition c,
                                              org.w3c.dom.Node e)
                                       throws XmlQueryParser.ParseException

Throws:

XmlQueryParser.ParseException

parseEquality

protected static Equality parseEquality(org.w3c.dom.Node e)
                                 throws XmlQueryParser.ParseException

Parse an equality. XML syntax:

 <equals>
   <x>…</x>
   <y>…</y>
 </equals>
 

where x and y are either attribute or value

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseAttribute

protected static Attribute parseAttribute(org.w3c.dom.Node e)
                                   throws XmlQueryParser.ParseException

Parse an attribute. XML syntax:

 <attribute>name</attribute>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseVariableTable

protected static VariableTable parseVariableTable(org.w3c.dom.Node e)
                                           throws XmlQueryParser.ParseException

Parse a table. XML syntax:

 <table>name</table>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseTable

protected static Table parseTable(org.w3c.dom.Node e)
                           throws XmlQueryParser.ParseException

Parse a table. XML syntax:

 <table>name</table>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseValue

protected static Value parseValue(org.w3c.dom.Node e)
                           throws XmlQueryParser.ParseException

Parse a value. XML syntax:

 <value>name</value>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseTuple

protected static Tuple parseTuple(org.w3c.dom.Node e)
                           throws XmlQueryParser.ParseException

Parse a table tuple. XML syntax:

 <tuple>
   <attr>value</attr>
   <attr>value</attr>
   …
 </tuple>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException

parseSchema

protected static Schema parseSchema(org.w3c.dom.Node e)
                             throws XmlQueryParser.ParseException

Parse a schema. XML syntax:

 <schema>
   <attribute>…</attribute>
   <attribute>…</attribute>
   …
 </schema>
 

Parameters:

e - An XML DOM node

Returns:

Throws:

XmlQueryParser.ParseException