## org.jfree.data.xy
Class XYSeries

    java.lang.Object
      org.jfree.data.general.Series
          org.jfree.data.xy.XYSeries

All Implemented Interfaces:
  java.io.Serializable, java.lang.Cloneable

    public class XYSeries

extends Series
implements java.lang.Cloneable, java.io.Serializable

Represents a sequence of zero or more data items in the form (x, y). By default, items in the series will be sorted into ascending order by x-value, and duplicate x-values are permitted. Both the sorting and duplicate defaults can be changed in the constructor. Y-values can be `null` to represent missing values.

See Also:
  Serialized Form

Field Summary
`protected java.util.List` `data` Storage for the data items in the series.

Constructor Summary
`XYSeries(java.lang.Comparable key)` Creates a new empty series.
`XYSeries(java.lang.Comparable key, boolean autoSort)` Constructs a new empty series, with the auto-sort flag set as requested, and duplicate values allowed.
`XYSeries(java.lang.Comparable key, boolean autoSort, boolean allowDuplicateXValues)` Constructs a new xy-series that contains no data.

Method Summary
`void` `add(double x, double y)` Adds a data item to the series and sends a `SeriesChangeEvent` to all registered listeners.
`void` `add(double x, double y, boolean notify)` Adds a data item to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners.
`void` `add(double x, java.lang.Number y)` Adds a data item to the series and sends a `SeriesChangeEvent` to all registered listeners.
`void` `add(double x, java.lang.Number y, boolean notify)` Adds a data item to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners.
`void` `add(java.lang.Number x, java.lang.Number y)` Adds a new data item to the series (in the correct position if the `autoSort` flag is set for the series) and sends a `SeriesChangeEvent` to all registered listeners.
`void` `add(java.lang.Number x, java.lang.Number y, boolean notify)` Adds new data to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners.
`void` `add(XYDataItem item)` Adds a data item to the series and sends a `SeriesChangeEvent` to all registered listeners.
`void` `add(XYDataItem item, boolean notify)` Adds a data item to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners.
`XYDataItem` `addOrUpdate(double x, double y)` Adds or updates an item in the series and sends a `SeriesChangeEvent` to all registered listeners.
`XYDataItem` `addOrUpdate(java.lang.Number x, java.lang.Number y)` Adds or updates an item in the series and sends a `SeriesChangeEvent` to all registered listeners.
`XYDataItem` `addOrUpdate(XYDataItem item)` Adds or updates an item in the series and sends a `SeriesChangeEvent` to all registered listeners.
`void` `clear()` Removes all data items from the series and sends a `SeriesChangeEvent` to all registered listeners.
`java.lang.Object` `clone()` Returns a clone of the series.
`XYSeries` `createCopy(int start, int end)` Creates a new series by copying a subset of the data in this time series.
`void` `delete(int start, int end)` Deletes a range of items from the series and sends a `SeriesChangeEvent` to all registered listeners.
`boolean` `equals(java.lang.Object obj)` Tests this series for equality with an arbitrary object.
`boolean` `getAllowDuplicateXValues()` Returns a flag that controls whether duplicate x-values are allowed.
`boolean` `getAutoSort()` Returns the flag that controls whether the items in the series are automatically sorted.
`XYDataItem` `getDataItem(int index)` Return the data item with the specified index.
`int` `getItemCount()` Returns the number of items in the series.
`java.util.List` `getItems()` Returns the list of data items for the series (the list contains `XYDataItem` objects and is unmodifiable).
`int` `getMaximumItemCount()` Returns the maximum number of items that will be retained in the series.
`double` `getMaxX()` Returns the largest x-value in the series, ignoring any Double.NaN values.
`double` `getMaxY()` Returns the largest y-value in the series, ignoring any Double.NaN values.
`double` `getMinX()` Returns the smallest x-value in the series, ignoring any Double.NaN values.
`double` `getMinY()` Returns the smallest y-value in the series, ignoring any null and Double.NaN values.
`java.lang.Number` `getX(int index)` Returns the x-value at the specified index.
`java.lang.Number` `getY(int index)` Returns the y-value at the specified index.
`int` `hashCode()` Returns a hash code.
`int` `indexOf(java.lang.Number x)` Returns the index of the item with the specified x-value, or a negative index if the series does not contain an item with that x-value.
`XYDataItem` `remove(int index)` Removes the item at the specified index and sends a `SeriesChangeEvent` to all registered listeners.
`XYDataItem` `remove(java.lang.Number x)` Removes an item with the specified x-value and sends a `SeriesChangeEvent` to all registered listeners.
`void` `setMaximumItemCount(int maximum)` Sets the maximum number of items that will be retained in the series.
`double[][]` `toArray()` Returns a new array containing the x and y values from this series.
`void` `update(int index, java.lang.Number y)` Deprecated. Renamed `updateByIndex(int, Number)` to avoid confusion with the `update(Number, Number)` method.
`void` `update(java.lang.Number x, java.lang.Number y)` Updates an item in the series.
`void` `updateByIndex(int index, java.lang.Number y)` Updates the value of an item in the series and sends a `SeriesChangeEvent` to all registered listeners.

Methods inherited from class org.jfree.data.general.Series
`addChangeListener, addPropertyChangeListener, addVetoableChangeListener, firePropertyChange, fireSeriesChanged, fireVetoableChange, getDescription, getKey, getNotify, isEmpty, notifyListeners, removeChangeListener, removePropertyChangeListener, removeVetoableChangeListener, setDescription, setKey, setNotify`

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

Field Detail

### data

    protected java.util.List data

  Storage for the data items in the series.

Constructor Detail

### XYSeries

    public XYSeries(java.lang.Comparable key)

  Creates a new empty series. By default, items added to the series will be sorted into ascending order by x-value, and duplicate x-values will be allowed (these defaults can be modified with another constructor.

  Parameters:
    `key` - the series key (`null` not permitted).

### XYSeries

    public XYSeries(java.lang.Comparable key,
                    boolean autoSort)

  Constructs a new empty series, with the auto-sort flag set as requested, and duplicate values allowed.

  Parameters:
    `key` - the series key (`null` not permitted).
    `autoSort` - a flag that controls whether or not the items in the series are sorted.

### XYSeries

    public XYSeries(java.lang.Comparable key,
                    boolean autoSort,
                    boolean allowDuplicateXValues)

  Constructs a new xy-series that contains no data. You can specify whether or not duplicate x-values are allowed for the series.

  Parameters:
    `key` - the series key (`null` not permitted).
    `autoSort` - a flag that controls whether or not the items in the series are sorted.
    `allowDuplicateXValues` - a flag that controls whether duplicate x-values are allowed.

Method Detail

### getMinX

    public double getMinX()

  Returns the smallest x-value in the series, ignoring any Double.NaN values. This method returns Double.NaN if there is no smallest x-value (for example, when the series is empty).

  Returns:
    The smallest x-value.
  Since:
    1.0.13
  See Also:
    `getMaxX()`

### getMaxX

    public double getMaxX()

  Returns the largest x-value in the series, ignoring any Double.NaN values. This method returns Double.NaN if there is no largest x-value (for example, when the series is empty).

  Returns:
    The largest x-value.
  Since:
    1.0.13
  See Also:
    `getMinX()`

### getMinY

    public double getMinY()

  Returns the smallest y-value in the series, ignoring any null and Double.NaN values. This method returns Double.NaN if there is no smallest y-value (for example, when the series is empty).

  Returns:
    The smallest y-value.
  Since:
    1.0.13
  See Also:
    `getMaxY()`

### getMaxY

    public double getMaxY()

  Returns the largest y-value in the series, ignoring any Double.NaN values. This method returns Double.NaN if there is no largest y-value (for example, when the series is empty).

  Returns:
    The largest y-value.
  Since:
    1.0.13
  See Also:
    `getMinY()`

### getAutoSort

    public boolean getAutoSort()

  Returns the flag that controls whether the items in the series are automatically sorted. There is no setter for this flag, it must be defined in the series constructor.

  Returns:
    A boolean.

### getAllowDuplicateXValues

    public boolean getAllowDuplicateXValues()

  Returns a flag that controls whether duplicate x-values are allowed. This flag can only be set in the constructor.

  Returns:
    A boolean.

### getItemCount

    public int getItemCount()

  Returns the number of items in the series.

  Specified by:
    `getItemCount` in class `Series`
  Returns:
    The item count.
  See Also:
    `getItems()`

### getItems

    public java.util.List getItems()

  Returns the list of data items for the series (the list contains `XYDataItem` objects and is unmodifiable).

  Returns:
    The list of data items.

### getMaximumItemCount

    public int getMaximumItemCount()

  Returns the maximum number of items that will be retained in the series. The default value is `Integer.MAX_VALUE`.

  Returns:
    The maximum item count.
  See Also:
    `setMaximumItemCount(int)`

### setMaximumItemCount

    public void setMaximumItemCount(int maximum)

  Sets the maximum number of items that will be retained in the series. If you add a new item to the series such that the number of items will exceed the maximum item count, then the first element in the series is automatically removed, ensuring that the maximum item count is not exceeded.

  Typically this value is set before the series is populated with data, but if it is applied later, it may cause some items to be removed from the series (in which case a `SeriesChangeEvent` will be sent to all registered listeners).

  Parameters:
    `maximum` - the maximum number of items for the series.

### add

    public void add(XYDataItem item)

  Adds a data item to the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `item` - the (x, y) item (`null` not permitted).

### add

    public void add(double x,
                    double y)

  Adds a data item to the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `x` - the x value.
    `y` - the y value.

### add

    public void add(double x,
                    double y,
                    boolean notify)

  Adds a data item to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `x` - the x value.
    `y` - the y value.
    `notify` - a flag that controls whether or not a `SeriesChangeEvent` is sent to all registered listeners.

### add

    public void add(double x,
                    java.lang.Number y)

  Adds a data item to the series and sends a `SeriesChangeEvent` to all registered listeners. The unusual pairing of parameter types is to make it easier to add `null` y-values.

  Parameters:
    `x` - the x value.
    `y` - the y value (`null` permitted).

### add

    public void add(double x,
                    java.lang.Number y,
                    boolean notify)

  Adds a data item to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners. The unusual pairing of parameter types is to make it easier to add null y-values.

  Parameters:
    `x` - the x value.
    `y` - the y value (`null` permitted).
    `notify` - a flag that controls whether or not a `SeriesChangeEvent` is sent to all registered listeners.

### add

    public void add(java.lang.Number x,
                    java.lang.Number y)

  Adds a new data item to the series (in the correct position if the `autoSort` flag is set for the series) and sends a `SeriesChangeEvent` to all registered listeners.

  Throws an exception if the x-value is a duplicate AND the allowDuplicateXValues flag is false.

  Parameters:
    `x` - the x-value (`null` not permitted).
    `y` - the y-value (`null` permitted).
  Throws:
    `SeriesException` - if the x-value is a duplicate and the `allowDuplicateXValues` flag is not set for this series.

### add

    public void add(java.lang.Number x,
                    java.lang.Number y,
                    boolean notify)

  Adds new data to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners.

  Throws an exception if the x-value is a duplicate AND the allowDuplicateXValues flag is false.

  Parameters:
    `x` - the x-value (`null` not permitted).
    `y` - the y-value (`null` permitted).
    `notify` - a flag the controls whether or not a `SeriesChangeEvent` is sent to all registered listeners.

### add

    public void add(XYDataItem item,
                    boolean notify)

  Adds a data item to the series and, if requested, sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `item` - the (x, y) item (`null` not permitted).
    `notify` - a flag that controls whether or not a `SeriesChangeEvent` is sent to all registered listeners.

### delete

    public void delete(int start,
                       int end)

  Deletes a range of items from the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `start` - the start index (zero-based).
    `end` - the end index (zero-based).

### remove

    public XYDataItem remove(int index)

  Removes the item at the specified index and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `index` - the index.
  Returns:
    The item removed.

### remove

    public XYDataItem remove(java.lang.Number x)

  Removes an item with the specified x-value and sends a `SeriesChangeEvent` to all registered listeners. Note that when a series permits multiple items with the same x-value, this method could remove any one of the items with that x-value.

  Parameters:
    `x` - the x-value.
  Returns:
    The item removed.

### clear

    public void clear()

  Removes all data items from the series and sends a `SeriesChangeEvent` to all registered listeners.

### getDataItem

    public XYDataItem getDataItem(int index)

  Return the data item with the specified index.

  Parameters:
    `index` - the index.
  Returns:
    The data item with the specified index.

### getX

    public java.lang.Number getX(int index)

  Returns the x-value at the specified index.

  Parameters:
    `index` - the index (zero-based).
  Returns:
    The x-value (never `null`).

### getY

    public java.lang.Number getY(int index)

  Returns the y-value at the specified index.

  Parameters:
    `index` - the index (zero-based).
  Returns:
    The y-value (possibly `null`).

### update

    public void update(int index,
                       java.lang.Number y)

  Deprecated. Renamed `updateByIndex(int, Number)` to avoid confusion with the `update(Number, Number)` method.

  Updates the value of an item in the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `index` - the item (zero based index).
    `y` - the new value (`null` permitted).

### updateByIndex

    public void updateByIndex(int index,
                              java.lang.Number y)

  Updates the value of an item in the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `index` - the item (zero based index).
    `y` - the new value (`null` permitted).
  Since:
    1.0.1

### update

    public void update(java.lang.Number x,
                       java.lang.Number y)

  Updates an item in the series.

  Parameters:
    `x` - the x-value (`null` not permitted).
    `y` - the y-value (`null` permitted).
  Throws:
    `SeriesException` - if there is no existing item with the specified x-value.

### addOrUpdate

    public XYDataItem addOrUpdate(double x,
                                  double y)

  Adds or updates an item in the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `x` - the x-value.
    `y` - the y-value.
  Returns:
    The item that was overwritten, if any.
  Since:
    1.0.10

### addOrUpdate

    public XYDataItem addOrUpdate(java.lang.Number x,
                                  java.lang.Number y)

  Adds or updates an item in the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `x` - the x-value (`null` not permitted).
    `y` - the y-value (`null` permitted).
  Returns:
    A copy of the overwritten data item, or `null` if no item was overwritten.

### addOrUpdate

    public XYDataItem addOrUpdate(XYDataItem item)

  Adds or updates an item in the series and sends a `SeriesChangeEvent` to all registered listeners.

  Parameters:
    `item` - the data item (`null` not permitted).
  Returns:
    A copy of the overwritten data item, or `null` if no item was overwritten.
  Since:
    1.0.14

### indexOf

    public int indexOf(java.lang.Number x)

  Returns the index of the item with the specified x-value, or a negative index if the series does not contain an item with that x-value. Be aware that for an unsorted series, the index is found by iterating through all items in the series.

  Parameters:
    `x` - the x-value (`null` not permitted).
  Returns:
    The index.

### toArray

    public double[][] toArray()

  Returns a new array containing the x and y values from this series.

  Returns:
    A new array containing the x and y values from this series.
  Since:
    1.0.4

### clone

    public java.lang.Object clone()
                           throws java.lang.CloneNotSupportedException

  Returns a clone of the series.

  Overrides:
    `clone` in class `Series`
  Returns:
    A clone of the series.
  Throws:
    `java.lang.CloneNotSupportedException` - if there is a cloning problem.

### createCopy

    public XYSeries createCopy(int start,
                               int end)
                        throws java.lang.CloneNotSupportedException

  Creates a new series by copying a subset of the data in this time series.

  Parameters:
    `start` - the index of the first item to copy.
    `end` - the index of the last item to copy.
  Returns:
    A series containing a copy of this series from start until end.
  Throws:
    `java.lang.CloneNotSupportedException` - if there is a cloning problem.

### equals

    public boolean equals(java.lang.Object obj)

  Tests this series for equality with an arbitrary object.

  Overrides:
    `equals` in class `Series`
  Parameters:
    `obj` - the object to test against for equality (`null` permitted).
  Returns:
    A boolean.

### hashCode

    public int hashCode()

  Returns a hash code.

  Overrides:
    `hashCode` in class `Series`
  Returns:
    A hash code.