AbstractQueryStepBuilder (org.chronos.chronosphere 1.0.0 API)

java.lang.Object
- org.chronos.chronosphere.impl.query.AbstractQueryStepBuilder<S,I,E>

All Implemented Interfaces:

QueryStepBuilder<S,E>, QueryStepBuilderInternal<S,E>, TraversalChainElement, TraversalTransformer<S,I,E>

Direct Known Subclasses:

NumericQueryStepBuilderImpl, ObjectQueryStepBuilderImpl
```
public abstract class AbstractQueryStepBuilder<S,I,E>
extends java.lang.Object
implements QueryStepBuilderInternal<S,E>, TraversalTransformer<S,I,E>
```

Field Summary

Fields
Modifier and Type Field and Description

protected TraversalChainElement previous

Fields
Modifier and Type	Field and Description
`protected TraversalChainElement`	`previous`

Constructor Summary

Constructors
Modifier Constructor and Description

protected AbstractQueryStepBuilder(TraversalChainElement previous)

Constructors
Modifier	Constructor and Description
`protected`	`AbstractQueryStepBuilder(TraversalChainElement previous)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`QueryStepBuilder<S,E>`	`and(QueryStepBuilder<E,?>... subqueries)`
`UntypedQueryStepBuilder<S,java.lang.Object>`	`back(java.lang.String stepName)` Exits the current traversal state and goes back to a named step, or a named set.
`long`	`count()` Counts the number of elements in the current result, and returns that count.
`QueryStepBuilder<S,E>`	`distinct()` Eliminates all duplicated values from the current result.
`QueryStepBuilder<S,E>`	`except(java.util.Set<?> elementsToExclude)` Removes all elements in the given set from the stream.
`QueryStepBuilder<S,E>`	`except(java.lang.String stepName)` Removes all elements from the given named step from this step.
`QueryStepBuilder<S,E>`	`filter(java.util.function.Predicate<E> predicate)` Applies the given filter predicate to all elements in the current result.
`<T> UntypedQueryStepBuilder<S,T>`	`flatMap(java.util.function.Function<E,java.util.Iterator<T>> function)` Uses the given function to map each element to an iterator of output elements.
`TraversalChainElement`	`getPrevious()`
`QueryStepBuilder<S,E>`	`limit(long limit)` Limits the number of elements in the result set to the given number.
`<T> UntypedQueryStepBuilder<S,T>`	`map(java.util.function.Function<E,T> function)` Uses the given function to map each element from the current result set to a new element.
`QueryStepBuilder<S,E>`	`named(java.lang.String stepName)` Assigns the given name to this `QueryStepBuilder`.
`QueryStepBuilder<S,E>`	`not(QueryStepBuilder<E,?> subquery)`
`QueryStepBuilder<S,E>`	`notNull()` Filters out and discards all `null` values from the current result set.
`QueryStepBuilder<S,E>`	`or(QueryStepBuilder<E,?>... subqueries)`
`QueryStepBuilder<S,E>`	`orderBy(java.util.Comparator<E> comparator)` Sorts the current result set by applying the given comparator.
`void`	`setPrevious(TraversalChainElement previous)`
`java.util.Iterator<E>`	`toIterator()` Creates an iterator over the elements in this query and returns it.
`java.util.List<E>`	`toList()` Calculates the result of this query and returns it as a `List`.
`java.util.Set<E>`	`toSet()` Calculates the result set of this query and returns it.
`java.util.stream.Stream<E>`	`toStream()` Converts this query into a `Stream`.
`UntypedQueryStepBuilder<S,java.lang.Object>`	`union(QueryStepBuilder<E,?>... subqueries)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.chronos.chronosphere.impl.query.traversal.TraversalTransformer
identity, transformTraversal

- Field Detail
  - previous
```
protected TraversalChainElement previous
```
- Constructor Detail
  - AbstractQueryStepBuilder
```
protected AbstractQueryStepBuilder(TraversalChainElement previous)
```
- Method Detail
  - filter
```
public QueryStepBuilder<S,E> filter(java.util.function.Predicate<E> predicate)
```
    Description copied from interface: QueryStepBuilder
    
    Applies the given filter predicate to all elements in the current result.
    
    Specified by:
    
    filter in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    predicate - The predicate to apply. Must not be null. All elements for which the predicate function returns false will be filtered out and discarded.
    
    Returns:
    
    The query builder, for method chaining. Never null.
  - limit
```
public QueryStepBuilder<S,E> limit(long limit)
```
    Description copied from interface: QueryStepBuilder
    
    Limits the number of elements in the result set to the given number.
    
    Please note that the order of elements is in general arbitrary. Therefore, usually a QueryStepBuilder.limit(long) is preceded by a QueryStepBuilder.orderBy(Comparator).
    
    Specified by:
    
    limit in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    limit - The limit to apply. Must not be negative.
    
    Returns:
    
    The query builder, for method chaining. Never null.
  - orderBy
```
public QueryStepBuilder<S,E> orderBy(java.util.Comparator<E> comparator)
```
    Description copied from interface: QueryStepBuilder
    
    Sorts the current result set by applying the given comparator.
    
    This method requires full resolution of all elements and is therefore non-lazy.
    
    Specified by:
    
    orderBy in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    comparator - The comparator to use. Must not be null.
    
    Returns:
    
    The query builder, for method chaining. Never null.
  - distinct
```
public QueryStepBuilder<S,E> distinct()
```
    Description copied from interface: QueryStepBuilder
    
    Eliminates all duplicated values from the current result.
    
    This method is lazy, but requires to keep track of the "already encountered" elements in a set. Therefore, RAM consumption on this method may be high if it is applied on very large result sets.
    
    Specified by:
    
    distinct in interface QueryStepBuilder<S,E>
    
    Returns:
    
    The distinct step builder, for method chaining. Never null.
  - map
```
public <T> UntypedQueryStepBuilder<S,T> map(java.util.function.Function<E,T> function)
```
    Description copied from interface: QueryStepBuilder
    
    Uses the given function to map each element from the current result set to a new element.
    
    Specified by:
    
    map in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    function - The mapping function to apply. Must not be null. Should be idempotent and side-effect free.
    
    Returns:
    
    The query step builder, for method chaining. Never null.
  - flatMap
```
public <T> UntypedQueryStepBuilder<S,T> flatMap(java.util.function.Function<E,java.util.Iterator<T>> function)
```
    Description copied from interface: QueryStepBuilder
    
    Uses the given function to map each element to an iterator of output elements. These output iterators will be concatenated and forwarded.
    
    Specified by:
    
    flatMap in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    function - The map function to apply. Must not be null. Should be idempotent and side-effect free.
    
    Returns:
    
    The query step builder, for method chaining. Never null.
  - notNull
```
public QueryStepBuilder<S,E> notNull()
```
    Description copied from interface: QueryStepBuilder
    Filters out and discards all null values from the current result set.
    
    This is the same as:
```
 query.filter(element -> element != null)
 
```
    Specified by:
    
    notNull in interface QueryStepBuilder<S,E>
    
    Returns:
    
    The query step builder, for method chaining. Never null.
    
    See Also:
    
    QueryStepBuilder.filter(Predicate)
  - named
```
public QueryStepBuilder<S,E> named(java.lang.String stepName)
```
    Description copied from interface: QueryStepBuilder
    
    Assigns the given name to this QueryStepBuilder.
    
    Note that only the step is named. When coming back to this step, the query result may be different than it was when it was first reached, depending on the traversal.
    
    Specified by:
    
    named in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    stepName - The name of the step. Must not be null. Must be unique within the query.
    
    Returns:
    
    The named step, for method chaining. Never null.
    
    See Also:
    
    QueryStepBuilder.back(String)
  - back
```
public UntypedQueryStepBuilder<S,java.lang.Object> back(java.lang.String stepName)
```
    Description copied from interface: QueryStepBuilder
    
    Exits the current traversal state and goes back to a named step, or a named set.
    
    Specified by:
    
    back in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    stepName - The name of the step to go back to. Must not be null, must refer to a named step.
    
    Returns:
    
    The step after going back, for method chaining. Never null.
    
    See Also:
    
    QueryStepBuilder.named(String)
  - except
```
public QueryStepBuilder<S,E> except(java.lang.String stepName)
```
    Description copied from interface: QueryStepBuilder
    
    Removes all elements from the given named step from this step.
    
    Specified by:
    
    except in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    stepName - The name of the step. Must not be null, must refer to a named step.
    
    Returns:
    
    The step after removing the elements in the given named step, for method chaining. Never null.
  - except
```
public QueryStepBuilder<S,E> except(java.util.Set<?> elementsToExclude)
```
    Description copied from interface: QueryStepBuilder
    
    Removes all elements in the given set from the stream.
    
    Specified by:
    
    except in interface QueryStepBuilder<S,E>
    
    Parameters:
    
    elementsToExclude - The elements to remove. Must not be null.
    
    Returns:
    
    The step after removing the elements in the given set, for method chaining. Never null.
  - union
```
public UntypedQueryStepBuilder<S,java.lang.Object> union(QueryStepBuilder<E,?>... subqueries)
```
    Specified by:
    
    union in interface QueryStepBuilder<S,E>
  - and
```
public QueryStepBuilder<S,E> and(QueryStepBuilder<E,?>... subqueries)
```
    Specified by:
    
    and in interface QueryStepBuilder<S,E>
  - or
```
public QueryStepBuilder<S,E> or(QueryStepBuilder<E,?>... subqueries)
```
    Specified by:
    
    or in interface QueryStepBuilder<S,E>
  - not
```
public QueryStepBuilder<S,E> not(QueryStepBuilder<E,?> subquery)
```
    Specified by:
    
    not in interface QueryStepBuilder<S,E>
  - toSet
```
public java.util.Set<E> toSet()
```
    Description copied from interface: QueryStepBuilder
    
    Calculates the result set of this query and returns it.
    
    Please note that iterating over the result set via QueryStepBuilder.toIterator() is in general faster and consumes less RAM than first converting the result into a set.
    
    Specified by:
    
    toSet in interface QueryStepBuilder<S,E>
    
    Returns:
    
    The result set. Never null. May be empty.
  - toList
```
public java.util.List<E> toList()
```
    Description copied from interface: QueryStepBuilder
    
    Calculates the result of this query and returns it as a List.
    
    Please note that iterating over the result via QueryStepBuilder.toIterator() is in general faster and consumes less RAM than first converting the result into a list.
    
    Specified by:
    
    toList in interface QueryStepBuilder<S,E>
    
    Returns:
    
    The result list. Never null. May be empty.
  - toStream
```
public java.util.stream.Stream<E> toStream()
```
    Description copied from interface: QueryStepBuilder
    
    Converts this query into a Stream.
    
    Specified by:
    
    toStream in interface QueryStepBuilder<S,E>
    
    Returns:
    
    The stream representation of this query.
  - count
```
public long count()
```
    Description copied from interface: QueryStepBuilder
    
    Counts the number of elements in the current result, and returns that count.
    
    Specified by:
    
    count in interface QueryStepBuilder<S,E>
    
    Returns:
    
    The count. Never negative, may be zero.
  - toIterator
```
public java.util.Iterator<E> toIterator()
```
    Description copied from interface: QueryStepBuilder
    
    Creates an iterator over the elements in this query and returns it.
    
    Specified by:
    
    toIterator in interface QueryStepBuilder<S,E>
    
    Returns:
    
    The iterator over the resulting elements. May be empty, but never null.
  - getPrevious
```
public TraversalChainElement getPrevious()
```
    Specified by:
    
    getPrevious in interface QueryStepBuilderInternal<S,E>
  - setPrevious
```
public void setPrevious(TraversalChainElement previous)
```
    Specified by:
    
    setPrevious in interface QueryStepBuilderInternal<S,E>

Class AbstractQueryStepBuilder<S,I,E>

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.chronos.chronosphere.impl.query.traversal.TraversalTransformer

Field Detail

previous

Constructor Detail

AbstractQueryStepBuilder

Method Detail

filter

limit

orderBy

distinct

map

flatMap

notNull

named

back

except

except

union

and

or

not

toSet

toList

toStream

count

toIterator

getPrevious

setPrevious