public class

SpinnerNumberModel

extends AbstractSpinnerModel
implements Serializable
java.lang.Object
   ↳ javax.swing.AbstractSpinnerModel
     ↳ javax.swing.SpinnerNumberModel

Class Overview

A SpinnerModel for sequences of numbers. The upper and lower bounds of the sequence are defined by properties called minimum and maximum. The size of the increase or decrease computed by the nextValue and previousValue methods is defined by a property called stepSize. The minimum and maximum properties can be null to indicate that the sequence has no lower or upper limit. All of the properties in this class are defined in terms of two generic types: Number and Comparable, so that all Java numeric types may be accommodated. Internally, there's only support for values whose type is one of the primitive Number types: Double, Float, Long, Integer, Short, or Byte.

To create a SpinnerNumberModel for the integer range zero to one hundred, with fifty as the initial value, one could write: 

 Integer value = new Integer(50);
 Integer min = new Integer(0);
 Integer max = new Integer(100);
 Integer step = new Integer(1);
 SpinnerNumberModel model = new SpinnerNumberModel(value, min, max, step);
 int fifty = model.getNumber().intValue();

Spinners for integers and doubles are common, so special constructors for these cases are provided. For example to create the model in the previous example, one could also write: 

 SpinnerNumberModel model = new SpinnerNumberModel(50, 0, 100, 1);

This model inherits a ChangeListener. The ChangeListeners are notified whenever the model's value, stepSize, minimum, or maximum properties changes.

See Also

Summary

[Expand]
Inherited Fields
From class javax.swing.AbstractSpinnerModel
Public Constructors
SpinnerNumberModel(Number value, Comparable minimum, Comparable maximum, Number stepSize)
Constructs a SpinnerModel that represents a closed sequence of numbers from minimum to maximum.
SpinnerNumberModel(int value, int minimum, int maximum, int stepSize)
Constructs a SpinnerNumberModel with the specified value, minimum/maximum bounds, and stepSize.
SpinnerNumberModel(double value, double minimum, double maximum, double stepSize)
Constructs a SpinnerNumberModel with the specified value, minimum/maximum bounds, and stepSize.
SpinnerNumberModel()
Constructs a SpinnerNumberModel with no minimum or maximum value, stepSize equal to one, and an initial value of zero.
Public Methods
Comparable getMaximum()
Returns the last number in the sequence.
Comparable getMinimum()
Returns the first number in this sequence.
Object getNextValue()
Returns the next number in the sequence.
Number getNumber()
Returns the value of the current element of the sequence.
Object getPreviousValue()
Returns the previous number in the sequence.
Number getStepSize()
Returns the size of the value change computed by the getNextValue and getPreviousValue methods.
Object getValue()
Returns the value of the current element of the sequence.
void setMaximum(Comparable maximum)
Changes the upper bound for numbers in this sequence.
void setMinimum(Comparable minimum)
Changes the lower bound for numbers in this sequence.
void setStepSize(Number stepSize)
Changes the size of the value change computed by the getNextValue and getPreviousValue methods.
void setValue(Object value)
Sets the current value for this sequence.
[Expand]
Inherited Methods
From class javax.swing.AbstractSpinnerModel
From class java.lang.Object
From interface javax.swing.SpinnerModel

Public Constructors

public SpinnerNumberModel (Number value, Comparable minimum, Comparable maximum, Number stepSize)

Constructs a SpinnerModel that represents a closed sequence of numbers from minimum to maximum. The nextValue and previousValue methods compute elements of the sequence by adding or subtracting stepSize respectively. All of the parameters must be mutually Comparable, value and stepSize must be instances of Integer Long, Float, or Double.

The minimum and maximum parameters can be null to indicate that the range doesn't have an upper or lower bound. If value or stepSize is null, or if both minimum and maximum are specified and mininum > maximum then an IllegalArgumentException is thrown. Similarly if (minimum <= value <= maximum) is false, an IllegalArgumentException is thrown.

Parameters
value the current (non null) value of the model
minimum the first number in the sequence or null
maximum the last number in the sequence or null
stepSize the difference between elements of the sequence
Throws
IllegalArgumentException if stepSize or value is null or if the following expression is false: minimum <= value <= maximum

public SpinnerNumberModel (int value, int minimum, int maximum, int stepSize)

Constructs a SpinnerNumberModel with the specified value, minimum/maximum bounds, and stepSize.

Parameters
value the current value of the model
minimum the first number in the sequence
maximum the last number in the sequence
stepSize the difference between elements of the sequence
Throws
IllegalArgumentException if the following expression is false: minimum <= value <= maximum

public SpinnerNumberModel (double value, double minimum, double maximum, double stepSize)

Constructs a SpinnerNumberModel with the specified value, minimum/maximum bounds, and stepSize.

Parameters
value the current value of the model
minimum the first number in the sequence
maximum the last number in the sequence
stepSize the difference between elements of the sequence
Throws
IllegalArgumentException if the following expression is false: minimum <= value <= maximum

public SpinnerNumberModel ()

Constructs a SpinnerNumberModel with no minimum or maximum value, stepSize equal to one, and an initial value of zero.

Public Methods

public Comparable getMaximum ()

Returns the last number in the sequence.

Returns
  • the value of the maximum property
See Also

public Comparable getMinimum ()

Returns the first number in this sequence.

Returns
  • the value of the minimum property
See Also

public Object getNextValue ()

Returns the next number in the sequence.

Returns
  • value + stepSize or null if the sum exceeds maximum.
See Also

public Number getNumber ()

Returns the value of the current element of the sequence.

Returns
  • the value property
See Also

public Object getPreviousValue ()

Returns the previous number in the sequence.

Returns
  • value - stepSize, or null if the sum is less than minimum.
See Also

public Number getStepSize ()

Returns the size of the value change computed by the getNextValue and getPreviousValue methods.

Returns
  • the value of the stepSize property
See Also

public Object getValue ()

Returns the value of the current element of the sequence.

Returns
  • the value property
See Also

public void setMaximum (Comparable maximum)

Changes the upper bound for numbers in this sequence. If maximum is null, then there is no upper bound. No bounds checking is done here; the new maximum value may invalidate the (minimum <= value < maximum) invariant enforced by the constructors. This is to simplify updating the model, naturally one should ensure that the invariant is true before calling the next, previous, or setValue methods.

Typically this property is a Number of the same type as the value however it's possible to use any Comparable with a compareTo method for a Number with the same type as the value. See setMinimum for an example.

This method fires a ChangeEvent if the maximum has changed.

Parameters
maximum a Comparable that has a compareTo method for Numbers with the same type as value
See Also

public void setMinimum (Comparable minimum)

Changes the lower bound for numbers in this sequence. If minimum is null, then there is no lower bound. No bounds checking is done here; the new minimum value may invalidate the (minimum <= value <= maximum) invariant enforced by the constructors. This is to simplify updating the model, naturally one should ensure that the invariant is true before calling the getNextValue, getPreviousValue, or setValue methods.

Typically this property is a Number of the same type as the value however it's possible to use any Comparable with a compareTo method for a Number with the same type as the value. For example if value was a Long, minimum might be a Date subclass defined like this: 

 MyDate extends Date {  // Date already implements Comparable
     public int compareTo(Long o) {
         long t = getTime();
         return (t < o.longValue() ? -1 : (t == o.longValue() ? 0 : 1));
     }
 }

This method fires a ChangeEvent if the minimum has changed.

Parameters
minimum a Comparable that has a compareTo method for Numbers with the same type as value
See Also

public void setStepSize (Number stepSize)

Changes the size of the value change computed by the getNextValue and getPreviousValue methods. An IllegalArgumentException is thrown if stepSize is null.

This method fires a ChangeEvent if the stepSize has changed.

Parameters
stepSize the size of the value change computed by the getNextValue and getPreviousValue methods
See Also

public void setValue (Object value)

Sets the current value for this sequence. If value is null, or not a Number, an IllegalArgumentException is thrown. No bounds checking is done here; the new value may invalidate the (minimum <= value <= maximum) invariant enforced by the constructors. It's also possible to set the value to be something that wouldn't naturally occur in the sequence, i.e. a value that's not modulo the stepSize. This is to simplify updating the model, and to accommodate spinners that don't want to restrict values that have been directly entered by the user. Naturally, one should ensure that the (minimum <= value <= maximum) invariant is true before calling the next, previous, or setValue methods.

This method fires a ChangeEvent if the value has changed.

Parameters
value the current (non null) Number for this sequence
Throws
IllegalArgumentException if value is null or not a Number
See Also