Package com.ultikits.ultitools.interfaces.impl.data

Class QueryImpl<T extends BaseDataEntity<String>>

java.lang.Object

com.ultikits.ultitools.interfaces.impl.data.QueryImpl<T>

Type Parameters:

T - the entity type

All Implemented Interfaces:

Query<T>

public class QueryImpl<T extends BaseDataEntity<String>>
extends Object
implements Query<T>

Default implementation of Query that wraps a DataOperator.

Equality conditions are delegated to the underlying DataOperator's getAll() method. Non-equality conditions (ne, gt, lt, gte, lte, like, in) are applied as in-memory filters. Ordering, limit, and offset are applied as in-memory post-processing.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static interface	QueryImpl.Predicate<T>	Simple functional interface for in-memory filtering (Java 8 compatible).

Field Summary

Fields

Modifier and Type	Field	Description
private String	currentColumn
private final List<WhereCondition>	eqConditions
private final List<QueryImpl.Predicate<T>>	filters
private int	limitCount
private int	offsetStart
private final DataOperator<T>	operator
private String	orderByColumn
private boolean	orderDesc

Constructor Summary

Constructors

Constructor	Description
QueryImpl(DataOperator<T> operator)

Method Summary

Modifier and Type	Method	Description
Query<T>	and(String column)	Add an AND condition on a column.
private int	compareField(T entity, String columnName, Object refValue)	Compare an entity's field value against a reference value.
private int	compareValues(Object a, Object b)	Compare two values.
long	count()	Count the number of matching results.
int	delete()	Deletes every row this query matches and returns the number of rows the backend actually removed (#521).
private int	deleteOne(Object id)
Query<T>	eq(Object value)	Equal to.
boolean	exists()	Check if any results match the query.
T	first()	Execute the query and return the first matching result, or null if none.
private Object	getFieldValue(T entity, String columnName)	Get a field value from an entity by column name.
Query<T>	gt(Object value)	Greater than.
Query<T>	gte(Object value)	Greater than or equal to.
Query<T>	in(Collection<?> values)	Value is in the given collection.
Query<T>	like(String pattern)	SQL LIKE pattern matching.
Query<T>	limit(int count)	Limit the number of results.
List<T>	list()	Execute the query and return all matching results.
Query<T>	lt(Object value)	Less than.
Query<T>	lte(Object value)	Less than or equal to.
Query<T>	ne(Object value)	Not equal to.
Query<T>	offset(int start)	Skip a number of results.
Query<T>	orderBy(String column)	Order results by column ascending.
Query<T>	orderByDesc(String column)	Order results by column descending.
Query<T>	where(String column)	Start a where condition on a column.

Methods inherited from class java.lang.Object

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

Field Details

operator

private final DataOperator<T extends BaseDataEntity<String>> operator

eqConditions

private final List<WhereCondition> eqConditions

filters

private final List<QueryImpl.Predicate<T extends BaseDataEntity<String>>> filters

currentColumn

private String currentColumn

orderByColumn

private String orderByColumn

orderDesc

private boolean orderDesc

limitCount

private int limitCount

offsetStart

private int offsetStart

Constructor Details

QueryImpl

public QueryImpl(DataOperator<T> operator)

Method Details

where

public Query<T> where(String column)

Description copied from interface: Query

Start a where condition on a column.

Specified by:

where in interface Query<T extends BaseDataEntity<String>>

Parameters:

column - the column name

Returns:

this query for chaining

and

public Query<T> and(String column)

Description copied from interface: Query

Add an AND condition on a column.

Specified by:

and in interface Query<T extends BaseDataEntity<String>>

Parameters:

column - the column name

Returns:

this query for chaining

eq

public Query<T> eq(Object value)

Description copied from interface: Query

Equal to.

Specified by:

eq in interface Query<T extends BaseDataEntity<String>>

Parameters:

value - the value to compare

Returns:

this query for chaining

ne

public Query<T> ne(Object value)

Description copied from interface: Query

Not equal to.

Specified by:

ne in interface Query<T extends BaseDataEntity<String>>

Parameters:

value - the value to compare

Returns:

this query for chaining

gt

public Query<T> gt(Object value)

Description copied from interface: Query

Greater than.

Specified by:

gt in interface Query<T extends BaseDataEntity<String>>

Parameters:

value - the value to compare

Returns:

this query for chaining

lt

public Query<T> lt(Object value)

Description copied from interface: Query

Less than.

Specified by:

lt in interface Query<T extends BaseDataEntity<String>>

Parameters:

value - the value to compare

Returns:

this query for chaining

gte

public Query<T> gte(Object value)

Description copied from interface: Query

Greater than or equal to.

Specified by:

gte in interface Query<T extends BaseDataEntity<String>>

Parameters:

value - the value to compare

Returns:

this query for chaining

lte

public Query<T> lte(Object value)

Description copied from interface: Query

Less than or equal to.

Specified by:

lte in interface Query<T extends BaseDataEntity<String>>

Parameters:

value - the value to compare

Returns:

this query for chaining

like

public Query<T> like(String pattern)

Description copied from interface: Query

SQL LIKE pattern matching.

Specified by:

like in interface Query<T extends BaseDataEntity<String>>

Parameters:

pattern - the LIKE pattern (use % for wildcard)

Returns:

this query for chaining

in

public Query<T> in(Collection<?> values)

Description copied from interface: Query

Value is in the given collection.

Specified by:

in in interface Query<T extends BaseDataEntity<String>>

Parameters:

values - the collection of allowed values

Returns:

this query for chaining

orderBy

public Query<T> orderBy(String column)

Description copied from interface: Query

Order results by column ascending.

Specified by:

orderBy in interface Query<T extends BaseDataEntity<String>>

Parameters:

column - the column to order by

Returns:

this query for chaining

orderByDesc

public Query<T> orderByDesc(String column)

Description copied from interface: Query

Order results by column descending.

Specified by:

orderByDesc in interface Query<T extends BaseDataEntity<String>>

Parameters:

column - the column to order by

Returns:

this query for chaining

limit

public Query<T> limit(int count)

Description copied from interface: Query

Limit the number of results.

Specified by:

limit in interface Query<T extends BaseDataEntity<String>>

Parameters:

count - the maximum number of results

Returns:

this query for chaining

offset

public Query<T> offset(int start)

Description copied from interface: Query

Skip a number of results.

Specified by:

offset in interface Query<T extends BaseDataEntity<String>>

Parameters:

start - the number of results to skip

Returns:

this query for chaining

list

public List<T> list()

Description copied from interface: Query

Execute the query and return all matching results.

Specified by:

list in interface Query<T extends BaseDataEntity<String>>

Returns:

list of matching entities

first

public T first()

Description copied from interface: Query

Execute the query and return the first matching result, or null if none.

Specified by:

first in interface Query<T extends BaseDataEntity<String>>

Returns:

the first matching entity, or null

exists

public boolean exists()

Description copied from interface: Query

Check if any results match the query.

Specified by:

exists in interface Query<T extends BaseDataEntity<String>>

Returns:

true if at least one result exists

count

public long count()

Description copied from interface: Query

Count the number of matching results.

Specified by:

count in interface Query<T extends BaseDataEntity<String>>

Returns:

the count of matching results

delete

public int delete()

Deletes every row this query matches and returns the number of rows the backend actually removed (#521).

Before 6.3.0 this returned the number of rows the query matched, and a matched row with a null id was skipped yet still counted, so the value could report rows removed that were not. Now:

• the count comes from the backend: the framework's operators report each delete's affected rows through RowCountingDelete, so a matched row that another writer removed first is not counted. A third-party operator that does not implement it cannot report what its delById removed, so a row is counted only if it existed immediately before that call and is gone after it; a row another writer removes during that one call is the only case this can still count;
• a matched row with a null id cannot be addressed by any delete, so it is refused with a DataAccessException naming the entity type before anything is deleted, instead of being skipped silently.

Specified by:

delete in interface Query<T extends BaseDataEntity<String>>

Returns:

the number of rows removed

Throws:

DataAccessException - if a matched row has a null id; nothing is deleted then

deleteOne

private int deleteOne(Object id)

getFieldValue

private Object getFieldValue(T entity,
 String columnName)

Get a field value from an entity by column name. Maps column name (snake_case) to Java field via @Column annotation.

compareField

private int compareField(T entity,
 String columnName,
 Object refValue)

Compare an entity's field value against a reference value. Returns negative, zero, or positive.

compareValues

private int compareValues(Object a,
 Object b)

Compare two values. Handles Comparable types and null safety.