org.jdbdt

Class DataSet

java.lang.Object

org.jdbdt.DataSet

Direct Known Subclasses:

TypedDataSet

public class DataSet
extends Object

Data set.

A data set represents a collection of database rows.

Since:

1.0

Constructor Summary

Constructors

Constructor and Description
DataSet(DataSource ds) Constructs a new data set.

Method Summary

Modifier and Type	Method and Description
DataSet	add(DataSet other) Add rows of given data set to this data set.
DataSetBuilder	build() Create a builder for this data set.
static DataSet	copyOf(DataSet data) Create data set with the same contents of given data set.
static DataSet	first(DataSet data, int count) Create sub-set with the first n rows.
DataSource	getSource() Get data source.
boolean	isEmpty() Check if the data set is empty.
boolean	isReadOnly() Check if the data set is read-only.
static DataSet	join(DataSet... dataSets) Create data set that results from joining several data sets.
static DataSet	last(DataSet data, int n) Create sub-set with the last n rows.
DataSet	row(Object... columnValues) Add a row to the data set.
DataSet	rows(Object[][] rows) Add rows to the data set.
void	setReadOnly() Set data set as read-only.
static DataSet	singleton(DataSet data, int index) Create a data set with only one row from the given data set.
int	size() Get size of data set.
static DataSet	subset(DataSet data, int startIndex, int count) Create a subset of the rows of given data set.
String	toString() Get textual representation of the data set.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataSet

public DataSet(DataSource ds)

Constructs a new data set.

Parameters:

ds - Data source.

Method Detail

isReadOnly

public final boolean isReadOnly()

Check if the data set is read-only.

Adding rows to a read-only data set will result in an exception of type InvalidOperationException.

Returns:

true if data set is read-only.

See Also:

setReadOnly()

setReadOnly

public final void setReadOnly()

Set data set as read-only.

Adding rows to a read-only data set will result in an exception of type InvalidOperationException. The read-only setting cannot be disabled after this method is called.

See Also:

isReadOnly()

getSource

public final DataSource getSource()

Get data source.

Returns:

The data source associated to this data set.

build

public final DataSetBuilder build()

Create a builder for this data set.

Returns:

A new builder for this data set.

isEmpty

public final boolean isEmpty()

Check if the data set is empty.

Returns:

true is the data set has no rows.

size

public final int size()

Get size of data set.

Returns:

The number of rows in the set.

row

@SafeVarargs
public final DataSet row(Object... columnValues)

Add a row to the data set.

Parameters:

columnValues - Column values forming a row.

Returns:

The data set instance (for chained calls).

Throws:

InvalidOperationException - if this data set is read-only.

See Also:

rows(Object[][]), add(DataSet), isReadOnly()

rows

public final DataSet rows(Object[][] rows)

Add rows to the data set.

Parameters:

rows - Array of rows.

Returns:

The data set instance (for chained calls).

Throws:

InvalidOperationException - if this data set is read-only.

See Also:

row(Object...), add(DataSet), isReadOnly()

add

public final DataSet add(DataSet other)

Add rows of given data set to this data set.

Parameters:

other - The other data set.

Returns:

The data set instance (for chained calls).

Throws:

InvalidOperationException - if this data set is read-only, or if the data source of the other data set differs from this one.

See Also:

row(Object...), rows(Object[][]), isReadOnly()

toString

public final String toString()

Get textual representation of the data set.

Overrides:

toString in class Object

Returns:

An "array-style" string with one entry per row in the data set.

Since:

1.1

See Also:

JDBDT.dump(DataSet, java.io.File), JDBDT.dump(DataSet, java.io.PrintStream)

subset

public static DataSet subset(DataSet data,
                             int startIndex,
                             int count)

Create a subset of the rows of given data set.

Parameters:

data - Source data set.

startIndex - Start index (from 0 to data.size()-1).

count - Number of rows.

Returns:

A new data set containing the rows in the specified range.

Throws:

InvalidOperationException - if the given data set is null or if the specified column range is invalid.

singleton

public static DataSet singleton(DataSet data,
                                int index)

Create a data set with only one row from the given data set.

Parameters:

data - Source data set.

index - Row index (from 0 to data.size()-1).

Returns:

A new data set containing the index-th row of the source data set.

Throws:

InvalidOperationException - if the given data set is null or if the specified column index is invalid.

first

public static DataSet first(DataSet data,
                            int count)

Create sub-set with the first n rows.

Parameters:

data - Source data set.

count - Number of rows.

Returns:

A new data set containing the first count rows in the source data set.

Throws:

InvalidOperationException - if the given data set is null or if the value of n is invalid.

last

public static DataSet last(DataSet data,
                           int n)

Create sub-set with the last n rows.

Parameters:

data - Source data set.

n - Number of rows.

Returns:

A new data set containing the last n rows in the source data set.

Throws:

InvalidOperationException - if the given data set is null or if the value of n is invalid.

copyOf

public static DataSet copyOf(DataSet data)

Create data set with the same contents of given data set.

Parameters:

data - Source data set.

Returns:

A new data set containing all rows in the source data set.

Throws:

InvalidOperationException - if given data set is null.

join

@SafeVarargs
public static DataSet join(DataSet... dataSets)

Create data set that results from joining several data sets.

Parameters:

dataSets - Data sets to join.

Returns:

A new data set containing the rows from all given data sets.

Throws:

InvalidOperationException - if dataSets is null or empty or if the data source is not the same for all data sets.