jimm.datavision.source
Class Query

java.lang.Object
  jimm.datavision.source.Query

All Implemented Interfaces:

Writeable

Direct Known Subclasses:

CharSepQuery, ObjectQuery, SQLQuery

public class Query
extends java.lang.Object
implements Writeable

A data source query.

Author:

Jim Menard, jimm@io.com

Field Summary

protected java.util.ArrayList	joins
protected Report	report
protected java.util.ArrayList	selectables
static int	SORT_ASCENDING
static int	SORT_DESCENDING
static int	SORT_UNDEFINED
protected java.util.ArrayList	sortOrders
protected java.util.ArrayList	sortSelectables
protected java.lang.String	whereClause

Constructor Summary

Query(Report r)
Constructor.

Method Summary

void	addAllJoins(java.util.Collection coll) Adds all joins in the collection to our list.
void	addJoin(Join join) Adds a join to the list of joins used by this query.
void	addSort(Selectable sel, int order) Adds a sort order for the specified selectable.
void	clearJoins() Removes all joins in the collection from our list.
void	clearSorts() Removes all sorts from our list.
boolean	containsReferenceTo(Parameter p) Returns true if the specified parameter exists within this query's where clause.
void	findSelectablesUsed() Builds collections of the selectables actually used in the report.
java.lang.String	getEditableWhereClause() Returns the where clause fit for human consumption.
int	getNumSelectables() Returns the number of selectables in the query.
java.lang.String	getWhereClause() Returns the raw where clause string; may be null.
int	indexOfSelectable(Selectable selectable) Returns the index of the specified selectable.
java.util.Iterator	joins() Returns an iterator over all the joins used by this query.
void	reloadColumns(DataSource dataSource) Called from DataSource.reloadColumns, this method gives the query source a chance to tell its ancillary objects (such as joins and the sort) to reload selectable objects.
void	removeJoin(Join join) Removes a join from the list of joins used by this query.
void	removeSort(Selectable sel) Removes a sorting from the list.
java.util.Iterator	selectables() Returns an iterator over all selectables.
void	setEditableWhereClause(java.lang.String newWhereClause) Sets the where clause (may be null).
void	setWhereClause(java.lang.String newWhereClause) Sets the where clause (may be null).
java.util.Iterator	sortedSelectables() Returns an iterator over all the sorted selectables used by this query.
int	sortOrderOf(Selectable sel) Returns the sort order (SORT_DESCENDING, SORT_ASCENDING, or SORT_UNDEFINED) of the specified selectable.
protected void	writeExtras(XMLWriter out) This method exists so subclasses can write out extra information.
void	writeXML(XMLWriter out) Writes this query as an XML tag.

Methods inherited from class java.lang.Object

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

Field Detail

SORT_UNDEFINED

public static final int SORT_UNDEFINED

See Also:

Constant Field Values

SORT_DESCENDING

public static final int SORT_DESCENDING

See Also:

Constant Field Values

SORT_ASCENDING

public static final int SORT_ASCENDING

See Also:

Constant Field Values

report

protected Report report

joins

protected java.util.ArrayList joins

whereClause

protected java.lang.String whereClause

sortSelectables

protected java.util.ArrayList sortSelectables

sortOrders

protected java.util.ArrayList sortOrders

selectables

protected java.util.ArrayList selectables

Constructor Detail

Query

public Query(Report r)

Constructor.

Parameters:

r - the report for which this query will retrieve data

Method Detail

containsReferenceTo

public boolean containsReferenceTo(Parameter p)

Returns true if the specified parameter exists within this query's where clause.

Parameters:

p - a parameter

Returns:

true if the specified parameter exists within the where clause

addJoin

public void addJoin(Join join)

Adds a join to the list of joins used by this query.

Parameters:

join - a join

addAllJoins

public void addAllJoins(java.util.Collection coll)

Adds all joins in the collection to our list.

Parameters:

coll - a collection of joins

removeJoin

public void removeJoin(Join join)

Removes a join from the list of joins used by this query.

Parameters:

join - a join

clearJoins

public void clearJoins()

Removes all joins in the collection from our list.

joins

public java.util.Iterator joins()

Returns an iterator over all the joins used by this query.

Returns:

an iterator over all the joins

getEditableWhereClause

public java.lang.String getEditableWhereClause()

Returns the where clause fit for human consumption. This mainly means that we substitute formula, parameter, and user column id numbers with names. Called from a where clause editor. This code assumes that curly braces are never nested.

Returns:

the eval string with formula, parameter, and user column id numbers replaced with names

See Also:

WhereClauseWin

getWhereClause

public java.lang.String getWhereClause()

Returns the raw where clause string; may be null.

Returns:

the where clause string; may be null

setEditableWhereClause

public void setEditableWhereClause(java.lang.String newWhereClause)

Sets the where clause (may be null). The string passed to us contains parameter and formula display strings, not their "real" formulaString representations. Translate the latter into the former before saving this string.

Parameters:

newWhereClause - a where clause string; may be null

setWhereClause

public void setWhereClause(java.lang.String newWhereClause)

Sets the where clause (may be null).

Parameters:

newWhereClause - a where clause string; may be null

addSort

public void addSort(Selectable sel,
                    int order)

Adds a sort order for the specified selectable. The first character of the order string is inspected. If it is a 'd' or 'D', then it's taken to mean "descending". Anything else will result in an "ascending" sort order.

Parameters:

sel - a selectable

order - either SORT_DESCENDING or SORT_ASCENDING

removeSort

public void removeSort(Selectable sel)

Removes a sorting from the list.

Parameters:

sel - a selectable

clearSorts

public void clearSorts()

Removes all sorts from our list.

selectables

public java.util.Iterator selectables()

Returns an iterator over all selectables.

Returns:

an iterator over all selectables

sortedSelectables

public java.util.Iterator sortedSelectables()

Returns an iterator over all the sorted selectables used by this query.

Returns:

an iterator

sortOrderOf

public int sortOrderOf(Selectable sel)

Returns the sort order (SORT_DESCENDING, SORT_ASCENDING, or SORT_UNDEFINED) of the specified selectable.

Parameters:

sel - a database selectable

Returns:

the sort order (SORT_DESCENDING, SORT_ASCENDING, or SORT_UNDEFINED) of the specified selectable.

indexOfSelectable

public int indexOfSelectable(Selectable selectable)

Returns the index of the specified selectable.

Parameters:

selectable - a database selectable

findSelectablesUsed

public void findSelectablesUsed()

Builds collections of the selectables actually used in the report.

getNumSelectables

public int getNumSelectables()

Returns the number of selectables in the query. Does not recalculate the selectables used; we assume this is being called after the qurey has been run or findSelectablesUsed() has been called.

Returns:

the number of selectables (database and user columns) in the query

reloadColumns

public void reloadColumns(DataSource dataSource)

Called from DataSource.reloadColumns, this method gives the query source a chance to tell its ancillary objects (such as joins and the sort) to reload selectable objects.

This is necessary, for example, after a SQL database data source has reloaded all of its table and column information. The old column objects no longer exist. New ones (with the same ids, we assume) have taken their place.

Parameters:

dataSource - the data source

writeXML

public void writeXML(XMLWriter out)

Writes this query as an XML tag. Writes all joins, where clauses, and sorts as well.

Specified by:

writeXML in interface Writeable

Parameters:

out - a writer that knows how to write XML

writeExtras

protected void writeExtras(XMLWriter out)

This method exists so subclasses can write out extra information.