de.erichseifert.gral.data

Class DataAccessor

java.lang.Object

de.erichseifert.gral.data.DataAccessor

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable<java.lang.Comparable<?>>

Direct Known Subclasses:

Row

public abstract class DataAccessor
extends java.lang.Object
implements java.lang.Iterable<java.lang.Comparable<?>>, java.io.Serializable

Abstract base for reading substructures of a data source, i.e. columns or rows. DataAccessors are iterable and provide utility methods for statistics and array conversion.

See Also:

DataSource, Serialized Form

Constructor Summary

Constructors

Constructor and Description
DataAccessor(DataSource source, int index) Initializes a new instance with the specified data source and an access index.

Method Summary

Modifier and Type	Method and Description
boolean	equals(java.lang.Object obj)
abstract java.lang.Comparable<?>	get(int index) Returns the value of the data source for the specified index.
int	getIndex() Returns the index to access the data source.
DataSource	getSource() Returns the data source containing this column.
double	getStatistics(java.lang.String key) Returns the specified statistical information for this data.
int	hashCode()
java.util.Iterator<java.lang.Comparable<?>>	iterator() Returns an iterator over the elements of this object.
abstract int	size() Returns the number of elements in this column.
java.lang.Comparable<?>[]	toArray(java.lang.Comparable<?>[] data) Converts the data column to an array.
java.lang.String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

DataAccessor

public DataAccessor(DataSource source,
                    int index)

Initializes a new instance with the specified data source and an access index.

Parameters:

source - Data source.

index - Column index.

Method Detail

getSource

public DataSource getSource()

Returns the data source containing this column.

Returns:

Data source containing this column.

getIndex

public int getIndex()

Returns the index to access the data source.

Returns:

Data index.

get

public abstract java.lang.Comparable<?> get(int index)

Returns the value of the data source for the specified index.

Parameters:

index - Index.

Returns:

Value of the accessed cell.

size

public abstract int size()

Returns the number of elements in this column.

Returns:

Number of elements

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

toArray

public java.lang.Comparable<?>[] toArray(java.lang.Comparable<?>[] data)

Converts the data column to an array.

Parameters:

data - Optional array as data sink. If array is null a new array will be created.

Returns:

Array with row data;

getStatistics

public double getStatistics(java.lang.String key)

Returns the specified statistical information for this data.

Parameters:

key - Requested Statistical information.

Returns:

Calculated value.

iterator

public java.util.Iterator<java.lang.Comparable<?>> iterator()

Returns an iterator over the elements of this object.

Specified by:

iterator in interface java.lang.Iterable<java.lang.Comparable<?>>

Returns:

an iterator.