org.datanucleus.query.compiler

Class QueryCompilation

java.lang.Object

org.datanucleus.query.compiler.QueryCompilation

All Implemented Interfaces:

Serializable

public class QueryCompilation
extends Object
implements Serializable

Representation of the components of a compiled java "string-based" query. Assumes that the query has the following forms

 SELECT {result} FROM {from} WHERE {filter} GROUP BY {grouping} HAVING {having} ORDER BY {order}
 UPDATE {from} SET {update} WHERE {filter}
 DELETE FROM {from} WHERE {filter}
 

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected String	candidateAlias Alias for the (primary) candidate.
protected Class	candidateClass Primary candidate class.
protected Expression	exprFilter Compiled filter expression
protected Expression[]	exprFrom Compiled from expression.
protected Expression[]	exprGrouping Compiled grouping expression.
protected Expression	exprHaving Compiled having expression.
protected Expression[]	exprOrdering Compiled ordering expression.
protected Expression[]	exprResult Compiled result expression.
protected Expression[]	exprUpdate Compiled update expression.
protected static Localiser	LOCALISER Localiser for messages.
protected String	queryLanguage Query language that this is a compilation for.
protected boolean	resultDistinct Whether the result is distinct.
protected boolean	returnsSingleRow Whether the query will return a single row.
protected Map<String,QueryCompilation>	subqueryCompilations Compilations of any subqueries, keyed by the subquery variable name.
protected SymbolTable	symtbl Compiled Symbol Table.

Constructor Summary

Constructors

Constructor and Description
QueryCompilation(Class candidateCls, String candidateAlias, SymbolTable symtbl, Expression[] results, Expression[] froms, Expression filter, Expression[] groupings, Expression having, Expression[] orderings, Expression[] updates)

Method Summary

Methods

Modifier and Type	Method and Description
void	addSubqueryCompilation(String alias, QueryCompilation compilation) Method to add the compilation for a subquery of this query.
String	debugString(String indent)
String	getCandidateAlias() Accessor for the candidate alias.
Class	getCandidateClass() Accessor for the candidate class.
QueryCompilation	getCompilationForSubquery(String alias) Accessor for the compilation for a subquery with the specified alias.
Expression	getExprFilter() Accessor for the filter expression.
Expression[]	getExprFrom() Accessor for any from expression(s).
Expression[]	getExprGrouping() Accessor for any grouping expression(s).
Expression	getExprHaving() Accessor for any having expression.
Expression[]	getExprOrdering() Accessor for any ordering expression(s).
Expression[]	getExprResult() Accessor for any result expression(s).
Expression[]	getExprUpdate() Accessor for any update expression(s).
ParameterExpression	getParameterExpressionForPosition(int pos)
String	getQueryLanguage()
boolean	getResultDistinct()
Class[]	getResultTypes() Accessor for the types of the result row components.
String[]	getSubqueryAliases() Accessor for the aliases for any subqueries in this compilation.
SymbolTable	getSymbolTable() Accessor for the symbol table for the query.
boolean	returnsSingleRow() Accessor for whether this query will return a single row.
void	setExprFilter(Expression filter)
void	setExprHaving(Expression having)
void	setQueryLanguage(String lang)
void	setResultDistinct()
void	setReturnsSingleRow()
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

LOCALISER

protected static final Localiser LOCALISER

Localiser for messages.

queryLanguage

protected String queryLanguage

Query language that this is a compilation for.

candidateClass

protected Class candidateClass

Primary candidate class.

candidateAlias

protected String candidateAlias

Alias for the (primary) candidate. Defaults to "this".

returnsSingleRow

protected boolean returnsSingleRow

Whether the query will return a single row.

symtbl

protected SymbolTable symtbl

Compiled Symbol Table.

resultDistinct

protected boolean resultDistinct

Whether the result is distinct.

exprResult

protected Expression[] exprResult

Compiled result expression.

exprFrom

protected Expression[] exprFrom

Compiled from expression.

exprUpdate

protected Expression[] exprUpdate

Compiled update expression.

exprFilter

protected Expression exprFilter

Compiled filter expression

exprGrouping

protected Expression[] exprGrouping

Compiled grouping expression.

exprHaving

protected Expression exprHaving

Compiled having expression.

exprOrdering

protected Expression[] exprOrdering

Compiled ordering expression.

subqueryCompilations

protected Map<String,QueryCompilation> subqueryCompilations

Compilations of any subqueries, keyed by the subquery variable name.

Constructor Detail

QueryCompilation

public QueryCompilation(Class candidateCls,
                String candidateAlias,
                SymbolTable symtbl,
                Expression[] results,
                Expression[] froms,
                Expression filter,
                Expression[] groupings,
                Expression having,
                Expression[] orderings,
                Expression[] updates)

Method Detail

setQueryLanguage

public void setQueryLanguage(String lang)

getQueryLanguage

public String getQueryLanguage()

setResultDistinct

public void setResultDistinct()

getResultDistinct

public boolean getResultDistinct()

setReturnsSingleRow

public void setReturnsSingleRow()

addSubqueryCompilation

public void addSubqueryCompilation(String alias,
                          QueryCompilation compilation)

Method to add the compilation for a subquery of this query.

Parameters:

alias - Alias for the subquery (variable name)

compilation - The compilation

getCompilationForSubquery

public QueryCompilation getCompilationForSubquery(String alias)

Accessor for the compilation for a subquery with the specified alias.

Parameters:

alias - Alias of subquery

Returns:

The compilation

getSubqueryAliases

public String[] getSubqueryAliases()

Accessor for the aliases for any subqueries in this compilation.

Returns:

The subquery aliases (if any)

returnsSingleRow

public boolean returnsSingleRow()

Accessor for whether this query will return a single row. This is true if all result selects are aggregates, or the user has set "unique" on the query.

Returns:

Whether this query will return a single row

getResultTypes

public Class[] getResultTypes()

Accessor for the types of the result row components. If no result is defined then will be an array of size 1 with element type "candidate".

Returns:

The result type(s)

getCandidateClass

public Class getCandidateClass()

Accessor for the candidate class.

Returns:

Candidate class

getCandidateAlias

public String getCandidateAlias()

Accessor for the candidate alias.

Returns:

Candidate alias

getSymbolTable

public SymbolTable getSymbolTable()

Accessor for the symbol table for the query.

Returns:

Symbol table, for parameter, variable lookup.

getExprResult

public Expression[] getExprResult()

Accessor for any result expression(s).

Returns:

The results

getExprFrom

public Expression[] getExprFrom()

Accessor for any from expression(s).

Returns:

The from clauses

getExprUpdate

public Expression[] getExprUpdate()

Accessor for any update expression(s).

Returns:

The updates

getExprFilter

public Expression getExprFilter()

Accessor for the filter expression.

Returns:

The filter

setExprFilter

public void setExprFilter(Expression filter)

getExprGrouping

public Expression[] getExprGrouping()

Accessor for any grouping expression(s).

Returns:

The grouping

getExprHaving

public Expression getExprHaving()

Accessor for any having expression.

Returns:

The having clause

setExprHaving

public void setExprHaving(Expression having)

getExprOrdering

public Expression[] getExprOrdering()

Accessor for any ordering expression(s).

Returns:

The ordering

getParameterExpressionForPosition

public ParameterExpression getParameterExpressionForPosition(int pos)

toString

public String toString()

Overrides:

toString in class Object

debugString

public String debugString(String indent)