com.sun.mdm.index.query
Class SingleQueryParser

java.lang.Object
  com.sun.mdm.index.query.QueryParser
      com.sun.mdm.index.query.SingleQueryParser

class SingleQueryParser

extends QueryParser

This Parser parses a QueryObject and produces a single SQL statement. The SQL statement would contain all the objects queried in QueryObject. Say if we have an object graph like: System Person Address Phone Alias This would produce SQL statement: select system.attributes, person.attributes, address.attributes, phone.attribute, alias.attributes from System, person, address, phone, alias where system.euid = person.euid and person.personid = address.personid and person.personid = phone.personid and person.personid = alias.personid The SQL statement created by it would produce lots of redundant data as it would use cartesian product among secondary objects. So this is more useful where the applications want tuples.

Constructor Summary

(package private)

SingleQueryParser(QueryObject qo) Creates a new instance of SingleQueryParser

Method Summary

(package private) void	checkForInvalidObjects(java.util.HashSet objects, QPath[] qpaths)
(package private) ConditionMap[]	createConditionMap(java.util.HashSet objects, QPath[] qpaths, Condition[] conditions)
(package private) QPath[]	createQPath(java.lang.String root, java.util.HashSet objectsHS) This is the actual method that creates the QPath[] each of which is a path from root to a different leaf.
(package private) java.util.HashSet	findObjects(QualifiedField[] selectFields)
(package private) java.util.HashSet	findObjects(QualifiedField[] selectFields, Condition[] conditions)
(package private) QueryObject	getQueryObject()
(package private) java.lang.String	getRoot()
(package private) java.lang.String	getRoot(QualifiedField[] selectFields, Condition[] conditions)
(package private) java.lang.String[]	getRootId() Returns full qualified path for root object primary key
static void	main(java.lang.String[] args) Test code
SQLDescWithBindParameters[]	parse() parses the QueryObject.
(package private) QualifiedField[]	qualify(java.lang.String[] selectFields)
(package private) void	setQueryObject(QueryObject qo)

Methods inherited from class java.lang.Object

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

Constructor Detail

SingleQueryParser

SingleQueryParser(QueryObject qo)

Creates a new instance of SingleQueryParser

Parameters:

qo - QueryObject

Method Detail

checkForInvalidObjects

void checkForInvalidObjects(java.util.HashSet objects,
                            QPath[] qpaths)
                      throws QMException

Throws:

QMException

createConditionMap

ConditionMap[] createConditionMap(java.util.HashSet objects,
                                  QPath[] qpaths,
                                  Condition[] conditions)

createQPath

QPath[] createQPath(java.lang.String root,
                    java.util.HashSet objectsHS)

This is the actual method that creates the QPath[] each of which is a path from root to a different leaf. So if objectsHS contain objects which belong to object graph: System Person Address Phone Alias, then QPaths would be { System, Person, Address }, { System, Person, Phone }, { System, Person, Alias } This method uses a variation of Breadth First Search algorithm to create SQL paths.

Parameters:

root - root of the tree that contains objects

objectsHS - HashSet contains the objects.

findObjects

java.util.HashSet findObjects(QualifiedField[] selectFields)

findObjects

java.util.HashSet findObjects(QualifiedField[] selectFields,
                              Condition[] conditions)

getQueryObject

QueryObject getQueryObject()

getRoot

java.lang.String getRoot()

getRoot

java.lang.String getRoot(QualifiedField[] selectFields,
                         Condition[] conditions)

getRootId

java.lang.String[] getRootId()
                       throws QMException

Returns full qualified path for root object primary key

Returns:

Throws:

QMException

main

public static void main(java.lang.String[] args)

Test code

Parameters:

args - args

parse

public SQLDescWithBindParameters[] parse()
                                  throws QMException

parses the QueryObject. This is the main interface method for parsing.

Specified by:

parse in class QueryParser

Returns:

SQLDescriptor[]. The return array is of size 1, since SingleQueryParser generates a single SQL statement.

Throws:

QMException - QMException

qualify

QualifiedField[] qualify(java.lang.String[] selectFields)
                   throws QMException

Throws:

QMException

setQueryObject

void setQueryObject(QueryObject qo)