tech.bitey.dataframe

Interface Cursor

All Superinterfaces:

Row

public interface Cursor
extends Row

A cursor for the rows of a DataFrame that allows the programmer to traverse the rows in either direction.

The difference between a cursor and an iterator is that an iterator returns a Row on a call to next() or previous(), while a cursor is a row.

Author:

biteytech@protonmail.com

Method Summary

Modifier and Type	Method and Description
boolean	hasNext() Returns true if this dataframe cursor has more rows to traverse in the forward direction.
boolean	hasPrevious() Returns true if this dataframe cursor has more rows to traverse in the backward direction.
void	next() Moves the cursor to the next Row in the dataframe.
void	previous() Returns the previous element in the dataframe and moves the cursor position backwards.

Methods inherited from interface tech.bitey.dataframe.Row

columnCount, get, get, getBigDecimal, getBigDecimal, getBoolean, getBoolean, getDate, getDate, getDateTime, getDateTime, getDouble, getDouble, getFloat, getFloat, getInt, getInt, getLong, getLong, getOrDefaultDouble, getOrDefaultDouble, getOrDefaultFloat, getOrDefaultFloat, getOrDefaultInt, getOrDefaultInt, getOrDefaultLong, getOrDefaultLong, getOrDefaultShort, getOrDefaultShort, getShort, getShort, getString, getString, isNull, isNull, rowIndex, yyyymmdd, yyyymmdd

Method Detail

hasNext

boolean hasNext()

Returns true if this dataframe cursor has more rows to traverse in the forward direction. (In other words, returns true if next() would move to a valid row rather than throwing an exception.)

Returns:

true if the cursor has more rows when traversing the dataframe in the forward direction

next

void next()

Moves the cursor to the next Row in the dataframe. This method may be called repeatedly to iterate through the dataframe, or intermixed with calls to previous() to go back and forth. (Note that alternating calls to next and previous will land on the same row repeatedly.)

Throws:

NoSuchElementException - if the dataframe has no next row

hasPrevious

boolean hasPrevious()

Returns true if this dataframe cursor has more rows to traverse in the backward direction. (In other words, returns true if previous() would move to a valid row rather than throwing an exception.)

Returns:

true if the cursor has more rows when traversing the dataframe in the backward direction

previous

void previous()

Returns the previous element in the dataframe and moves the cursor position backwards. This method may be called repeatedly to iterate through the dataframe backwards, or intermixed with calls to next() to go back and forth. (Note that alternating calls to next and previous will return the same element repeatedly.)

Throws:

NoSuchElementException - if the dataframe has no previous row