org.datanucleus.query.compiler
Class JavaQueryCompiler

java.lang.Object
  org.datanucleus.query.compiler.JavaQueryCompiler

All Implemented Interfaces:

SymbolResolver

Direct Known Subclasses:

JDOQLCompiler, JPQLCompiler

public abstract class JavaQueryCompiler
extends java.lang.Object
implements SymbolResolver

Typical implementation of a compiler for a java-based query language. The constructor takes in the components of the query, and the method compile() compiles it returning the compiled query, for use elsewhere.

Each "Expression" is effectively a tree of Expressions. You can navigate through each expression based on their type. For example, a DyadicExpression has a "left" and "right" and an operator between them. The left could also be a DyadicExpression, so you would navigate to its left/right components etc etc.

Field Summary

protected java.lang.String	candidateAlias Alias for the primary candidate.
protected java.lang.Class	candidateClass Primary candidate class (if defined).
protected java.util.Collection	candidates
protected boolean	caseSensitiveAliases
protected ClassLoaderResolver	clr
protected java.lang.String	filter
protected java.lang.String	from
protected java.lang.String	grouping
protected java.lang.String	having
protected Imports	imports
protected static Localiser	LOCALISER Localisation utility for output messages
protected MetaDataManager	metaDataManager
protected java.lang.String	ordering
protected java.lang.String	parameters
protected JavaQueryCompiler	parentCompiler
protected Parser	parser Parser specific to the type of query being compiled.
protected java.lang.String	result
protected SymbolTable	symtbl Compiled Symbol Table.
protected java.lang.String	update
protected java.lang.String	variables

Constructor Summary

JavaQueryCompiler(MetaDataManager metaDataManager, ClassLoaderResolver clr, java.lang.String from, java.lang.Class candidateClass, java.util.Collection candidates, java.lang.String filter, Imports imports, java.lang.String ordering, java.lang.String result, java.lang.String grouping, java.lang.String having, java.lang.String params, java.lang.String variables, java.lang.String update)

Method Summary

abstract QueryCompilation	compile(java.util.Map parameters, java.util.Map subqueryMap) Method to compile the query.
void	compileCandidatesParametersVariables(java.util.Map parameters) Compile the candidates, variables and parameters.
Expression	compileFilter() Compile the filter and return the compiled expression.
protected Expression[]	compileFrom() Method to compile the "from" clause (if present for the query language).
Expression[]	compileGrouping()
Expression	compileHaving()
Expression[]	compileOrdering()
Expression[]	compileResult()
Expression[]	compileUpdate()
abstract java.lang.String	getLanguage() Accessor for the query language name.
java.lang.Class	getPrimaryClass() Accessor for the candidate class of the query.
java.lang.Class	getType(java.util.List tuples)
protected abstract boolean	isKeyword(java.lang.String name) Method to return if the supplied name is a keyword.
java.lang.Class	resolveClass(java.lang.String className) Method to perform a lookup of the class name from the input name.
void	setParentQueryCompiler(JavaQueryCompiler compiler)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.datanucleus.query.symbol.SymbolResolver

caseSensitiveSymbolNames, supportsImplicitVariables

Field Detail

LOCALISER

protected static final Localiser LOCALISER

Localisation utility for output messages

parentCompiler

protected JavaQueryCompiler parentCompiler

metaDataManager

protected final MetaDataManager metaDataManager

clr

protected final ClassLoaderResolver clr

caseSensitiveAliases

protected boolean caseSensitiveAliases

candidateClass

protected java.lang.Class candidateClass

Primary candidate class (if defined).

candidateAlias

protected java.lang.String candidateAlias

Alias for the primary candidate. Default to "this" (JDOQL) but can be set.

from

protected java.lang.String from

candidates

protected java.util.Collection candidates

update

protected java.lang.String update

filter

protected java.lang.String filter

ordering

protected java.lang.String ordering

parameters

protected java.lang.String parameters

variables

protected java.lang.String variables

grouping

protected java.lang.String grouping

having

protected java.lang.String having

result

protected java.lang.String result

imports

protected Imports imports

symtbl

protected SymbolTable symtbl

Compiled Symbol Table.

parser

protected Parser parser

Parser specific to the type of query being compiled.

Constructor Detail

JavaQueryCompiler

public JavaQueryCompiler(MetaDataManager metaDataManager,
                         ClassLoaderResolver clr,
                         java.lang.String from,
                         java.lang.Class candidateClass,
                         java.util.Collection candidates,
                         java.lang.String filter,
                         Imports imports,
                         java.lang.String ordering,
                         java.lang.String result,
                         java.lang.String grouping,
                         java.lang.String having,
                         java.lang.String params,
                         java.lang.String variables,
                         java.lang.String update)

Method Detail

getLanguage

public abstract java.lang.String getLanguage()

Accessor for the query language name.

Returns:

Name of the query language.

setParentQueryCompiler

public void setParentQueryCompiler(JavaQueryCompiler compiler)

compile

public abstract QueryCompilation compile(java.util.Map parameters,
                                         java.util.Map subqueryMap)

Method to compile the query.

Parameters:

parameters - The parameter values keyed by name.

subqueryMap - Map of subqueries keyed by the subquery name

Returns:

The query compilation

compileCandidatesParametersVariables

public void compileCandidatesParametersVariables(java.util.Map parameters)

Compile the candidates, variables and parameters.

Parameters:

parameters - Map of parameter values keyed by their name

compileFrom

protected Expression[] compileFrom()

Method to compile the "from" clause (if present for the query language).

compileUpdate

public Expression[] compileUpdate()

compileFilter

public Expression compileFilter()

Compile the filter and return the compiled expression.

Returns:

The compiled expression

compileResult

public Expression[] compileResult()

compileGrouping

public Expression[] compileGrouping()

compileHaving

public Expression compileHaving()

compileOrdering

public Expression[] compileOrdering()

getPrimaryClass

public java.lang.Class getPrimaryClass()

Description copied from interface: SymbolResolver

Accessor for the candidate class of the query.

Specified by:

getPrimaryClass in interface SymbolResolver

Returns:

The candidate class

resolveClass

public java.lang.Class resolveClass(java.lang.String className)

Method to perform a lookup of the class name from the input name. Makes use of the query "imports" and the lookup to "entity name".

Specified by:

resolveClass in interface SymbolResolver

Parameters:

className - Name of the class

Returns:

The class corresponding to this name

Throws:

ClassNotResolvedException - thrown if not resolvable using imports or entity name

getType

public java.lang.Class getType(java.util.List tuples)

Specified by:

getType in interface SymbolResolver

isKeyword

protected abstract boolean isKeyword(java.lang.String name)

Method to return if the supplied name is a keyword. Keywords can only appear at particular places in a query so we need to detect for valid queries.

Parameters:

name - The name

Returns:

Whether it is a keyword