TraversableBase (Java Tool 1.2.2 API)

java.lang.Object
- org.osgl.util.FeaturedBase
- - org.osgl.util.TraversableBase<T>

All Implemented Interfaces:

Iterable<T>, C.Featured, C.Traversable<T>

Direct Known Subclasses:

SequenceBase
```
public abstract class TraversableBase<T>
extends FeaturedBase
implements C.Traversable<T>
```
Provide default implementation to some C.Traversable interface

Nested Class Summary
- Nested classes/interfaces inherited from interface org.osgl.util.C.Featured
  C.Featured.Factory

Constructor Summary

Constructors
Constructor and Description

TraversableBase()

Constructors
Constructor and Description
`TraversableBase()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`C.Traversable<T>`	`accept(Osgl.Function<? super T,?> visitor)` Iterate this `Traversable` with a visitor function.
`boolean`	`allMatch(Osgl.Function<? super T,Boolean> predicate)` Check if all elements match the predicate specified
`boolean`	`anyMatch(Osgl.Function<? super T,Boolean> predicate)` Check if any elements matches the predicate specified
`C.Traversable<T>`	`each(Osgl.Function<? super T,?> visitor)` Alias of `C.Traversable.accept(Osgl.Function)`
`C.Traversable<T>`	`eager()` Returns this traversable and turn off `C.Feature.LAZY`
`C.Traversable<T>`	`filter(Osgl.Function<? super T,Boolean> predicate)` Returns an new traversable that contains all elements in the current traversable except that does not pass the test of the filter function specified.
`Osgl.Option<T>`	`findOne(Osgl.Function<? super T,Boolean> predicate)` Iterate the traversal to check if any element applied to the predicate the iteration process stop when the element is found and return an option describing the element.
`<R> C.Traversable<R>`	`flatMap(Osgl.Function<? super T,? extends Iterable<? extends R>> mapper)` Returns a traversable consisting of the results of replacing each element of this stream with the contents of the iterable produced by applying the provided mapping function to each element.
`TraversableBase<T>`	`forEach(Osgl.Function<? super T,?> visitor)` Iterate through this traversal and apply the visitor function specified to each element iterated
`protected int`	`generateHashCode()` Sub class can override this method to provide more efficient algorithm to generate hash code.
`int`	`hashCode()` Iterate through the traversal to aggregate hash code of all element.
`protected EnumSet<C.Feature>`	`initFeatures()` Sub class should override this method to provide initial feature set for the feature based instance
`boolean`	`isEmpty()` Is this traversal empty?
`C.Traversable<T>`	`lazy()` Returns this traversable and try to turn on `C.Feature.LAZY`.
`<R> C.Traversable<R>`	`map(Osgl.Function<? super T,? extends R> mapper)` Returns an new traversable with a mapper function specified.
`boolean`	`noneMatch(Osgl.Function<? super T,Boolean> predicate)` Check if no elements matches the predicate specified.
`C.Traversable<T>`	`parallel()` Returns this traversable and try to turn on `C.Feature.PARALLEL`.
`Osgl.Option<T>`	`reduce(Osgl.Func2<T,T,T> accumulator)` Iterate through the traversal to apply the accumulator to the result of previous application and the element being iterated.
`<R> R`	`reduce(R identity, Osgl.Func2<R,T,R> accumulator)` Iterate through the traversal to apply the accumulator to the result of previous application and the element being iterated.
`C.Traversable<T>`	`sequential()` Returns this traversable and turn off `C.Feature.PARALLEL`

Methods inherited from class org.osgl.util.FeaturedBase
features_, features, is, setFeature, unsetFeature

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

Methods inherited from interface org.osgl.util.C.Traversable
size

Methods inherited from interface java.lang.Iterable
forEach, iterator, spliterator

Methods inherited from interface org.osgl.util.C.Featured
features, is

- Constructor Detail
  - TraversableBase
```
public TraversableBase()
```
- Method Detail
  - initFeatures
```
protected EnumSet<C.Feature> initFeatures()
```
    Description copied from class: FeaturedBase
    
    Sub class should override this method to provide initial feature set for the feature based instance
    
    Specified by:
    
    initFeatures in class FeaturedBase
    
    Returns:
    
    the initial feature set configuration
  - forEach
```
public TraversableBase<T> forEach(Osgl.Function<? super T,?> visitor)
```
    Iterate through this traversal and apply the visitor function specified to each element iterated
    
    Specified by:
    
    forEach in interface C.Traversable<T>
    
    Parameters:
    
    visitor -
    
    Returns:
    
    this Traversable instance
  - generateHashCode
```
protected int generateHashCode()
```
    Sub class can override this method to provide more efficient algorithm to generate hash code. The default implementation use Osgl.iterableHashCode(Iterable) to generate the hash code
    
    Returns:
    
    hash code of this traversal
  - hashCode
```
public int hashCode()
```
    Iterate through the traversal to aggregate hash code of all element. If the traversal is C.Feature.IMMUTABLE a cached hashcode will be generated at first time calling this method and returned directly for the following calls
    
    Overrides:
    
    hashCode in class Object
    
    Returns:
    
    the hash code of this traversal
  - lazy
```
public C.Traversable<T> lazy()
```
    Description copied from interface: C.Traversable
    
    Returns this traversable and try to turn on C.Feature.LAZY. If lazy is not supported then return this traversable directly without any state change
    
    Specified by:
    
    lazy in interface C.Traversable<T>
    
    Returns:
    
    this reference with lazy turned on if it is supported
  - eager
```
public C.Traversable<T> eager()
```
    Description copied from interface: C.Traversable
    
    Returns this traversable and turn off C.Feature.LAZY
    
    Specified by:
    
    eager in interface C.Traversable<T>
    
    Returns:
    
    this reference with lazy turned off
  - parallel
```
public C.Traversable<T> parallel()
```
    Description copied from interface: C.Traversable
    
    Returns this traversable and try to turn on C.Feature.PARALLEL. If this traversable does not support C.Feature.PARALLEL then return this traversable directly without any state change
    
    Specified by:
    
    parallel in interface C.Traversable<T>
    
    Returns:
    
    this reference with parallel turned on if parallel is supported
  - sequential
```
public C.Traversable<T> sequential()
```
    Description copied from interface: C.Traversable
    
    Returns this traversable and turn off C.Feature.PARALLEL
    
    Specified by:
    
    sequential in interface C.Traversable<T>
    
    Returns:
    
    this reference with parallel turned off
  - isEmpty
```
public boolean isEmpty()
```
    Description copied from interface: C.Traversable
    
    Is this traversal empty?
    
    Specified by:
    
    isEmpty in interface C.Traversable<T>
    
    Returns:
    
    true if the traversal is empty or false otherwise
  - reduce
```
public <R> R reduce(R identity,
                    Osgl.Func2<R,T,R> accumulator)
```
    Iterate through the traversal to apply the accumulator to the result of previous application and the element being iterated. If the traversal is empty then return the identity specified
    
    Specified by:
    
    reduce in interface C.Traversable<T>
    
    Type Parameters:
    
    R - the type of the identity and the return value
    
    Parameters:
    
    identity - the identity value for the accumulating function
    
    accumulator - the function the combine two values
    
    Returns:
    
    the reduce result
  - reduce
```
public Osgl.Option<T> reduce(Osgl.Func2<T,T,T> accumulator)
```
    Iterate through the traversal to apply the accumulator to the result of previous application and the element being iterated. If the traversal is empty then return $.Option#NONE, otherwise an $.Option wrapping the accumulated result is returned
    
    Specified by:
    
    reduce in interface C.Traversable<T>
    
    Parameters:
    
    accumulator - the function the combine two values
    
    Returns:
    
    _.NONE if the traversal is empty or an option describing the final accumulated value
  - findOne
```
public Osgl.Option<T> findOne(Osgl.Function<? super T,Boolean> predicate)
```
    Iterate the traversal to check if any element applied to the predicate the iteration process stop when the element is found and return an option describing the element. If no element applied to the predicate then $.Option#NONE is returned
    
    Specified by:
    
    findOne in interface C.Traversable<T>
    
    Parameters:
    
    predicate - the function map element to Boolean
    
    Returns:
    
    an option describing the element match the predicate or none if no such element found in the traversal
  - anyMatch
```
public boolean anyMatch(Osgl.Function<? super T,Boolean> predicate)
```
    Description copied from interface: C.Traversable
    
    Check if any elements matches the predicate specified
    
    Specified by:
    
    anyMatch in interface C.Traversable<T>
    
    Parameters:
    
    predicate - the function to test the element
    
    Returns:
    
    true if any element matches the predicate
  - noneMatch
```
public boolean noneMatch(Osgl.Function<? super T,Boolean> predicate)
```
    Description copied from interface: C.Traversable
    Check if no elements matches the predicate specified. This should be equivalent to:
```
      this.allMatch(_.F.negate(predicate));
 
```
    Specified by:
    
    noneMatch in interface C.Traversable<T>
    
    Parameters:
    
    predicate - the function to test the element
    
    Returns:
    
    true if none element matches the predicate
  - allMatch
```
public boolean allMatch(Osgl.Function<? super T,Boolean> predicate)
```
    Description copied from interface: C.Traversable
    
    Check if all elements match the predicate specified
    
    Specified by:
    
    allMatch in interface C.Traversable<T>
    
    Parameters:
    
    predicate - the function to test the element
    
    Returns:
    
    true if all elements match the predicate
  - accept
```
public C.Traversable<T> accept(Osgl.Function<? super T,?> visitor)
```
    Description copied from interface: C.Traversable
    
    Iterate this Traversable with a visitor function. This method does not specify the approach to iterate through this structure. The implementation might choose iterate from left to right, or vice versa. It might even choose to split the structure into multiple parts, and iterate through them in parallel
    
    Specified by:
    
    accept in interface C.Traversable<T>
    
    Parameters:
    
    visitor - a function that apply to element in this Traversable. The return value of the function is ignored
    
    Returns:
    
    this Traversable instance for chained call
  - each
```
public C.Traversable<T> each(Osgl.Function<? super T,?> visitor)
```
    Description copied from interface: C.Traversable
    
    Alias of C.Traversable.accept(Osgl.Function)
    
    Specified by:
    
    each in interface C.Traversable<T>
    
    Parameters:
    
    visitor - the visitor to tranverse the elements
    
    Returns:
    
    this Traversable instance
  - map
```
public <R> C.Traversable<R> map(Osgl.Function<? super T,? extends R> mapper)
```
    Description copied from interface: C.Traversable
    Returns an new traversable with a mapper function specified. The element in the new traversal is the result of the mapper function applied to this traversal element.
```
     Traversable traversable = C.list(23, _.NONE, null);
     assertEquals(C.list(true, false, false), traversal.map(_.F.NOT_NULL));
     assertEquals(C.list("23", "", ""), traversal.map(_.F.AS_STRING));
 
```
    For Lazy Traversable, it must use lazy evaluation for this method. Otherwise it is up to implementation to decide whether use lazy evaluation or not
    Specified by:
    
    map in interface C.Traversable<T>
    
    Type Parameters:
    
    R - the element type of the new traversal
    
    Parameters:
    
    mapper - the function that applied to element in this traversal and returns element in the result traversal
    
    Returns:
    
    the new traversal contains results of the mapper function applied to this traversal
  - flatMap
```
public <R> C.Traversable<R> flatMap(Osgl.Function<? super T,? extends Iterable<? extends R>> mapper)
```
    Description copied from interface: C.Traversable
    
    Returns a traversable consisting of the results of replacing each element of this stream with the contents of the iterable produced by applying the provided mapping function to each element. If the result of the mapping function is null, this is treated as if the result is an empty traversable.
    
    Specified by:
    
    flatMap in interface C.Traversable<T>
    
    Type Parameters:
    
    R - the element type of the the new traversable
    
    Parameters:
    
    mapper - the function produce an iterable when applied to an element
    
    Returns:
    
    the new traversable
  - filter
```
public C.Traversable<T> filter(Osgl.Function<? super T,Boolean> predicate)
```
    Description copied from interface: C.Traversable
    Returns an new traversable that contains all elements in the current traversable except that does not pass the test of the filter function specified.
```
     Traversable traversable = C.list(-1, 0, 1, -3, 7);
     Traversable filtered = traversable.filter(_.F.gt(0));
     assertTrue(filtered.contains(1));
     assertFalse(filtered.contains(-3));
 
```
    Specified by:
    
    filter in interface C.Traversable<T>
    
    Parameters:
    
    predicate - the function that test if the element in the traversable should be kept in the resulting traversable. When applying the filter function to the element, if the result is true then the element will be kept in the resulting traversable.
    
    Returns:
    
    the new traversable consists of elements passed the filter function test

Class TraversableBase<T>

Nested Class Summary

Nested classes/interfaces inherited from interface org.osgl.util.C.Featured

Constructor Summary

Method Summary

Methods inherited from class org.osgl.util.FeaturedBase

Methods inherited from class java.lang.Object

Methods inherited from interface org.osgl.util.C.Traversable

Methods inherited from interface java.lang.Iterable

Methods inherited from interface org.osgl.util.C.Featured

Constructor Detail

TraversableBase

Method Detail

initFeatures

forEach

generateHashCode

hashCode

lazy

eager

parallel

sequential

isEmpty

reduce

reduce

findOne

anyMatch

noneMatch

allMatch

accept

each

map

flatMap

filter