Class NumberFormatter

javax.swing.text.NumberFormatter

All Implemented Interfaces:: Serializable, Cloneable

public class NumberFormatter extends InternationalFormatter

NumberFormatter subclasses InternationalFormatter adding special behavior for numbers. Among the specializations are (these are only used if the NumberFormatter does not display invalid numbers, for example, setAllowsInvalid(false)):

Pressing +/- (- is determined from the DecimalFormatSymbols associated with the DecimalFormat) in any field but the exponent field will attempt to change the sign of the number to positive/negative.
Pressing +/- (- is determined from the DecimalFormatSymbols associated with the DecimalFormat) in the exponent field will attempt to change the sign of the exponent to positive/negative.

If you are displaying scientific numbers, you may wish to turn on overwrite mode, setOverwriteMode(true). For example:

DecimalFormat decimalFormat = new DecimalFormat("0.000E0");
NumberFormatter textFormatter = new NumberFormatter(decimalFormat);
textFormatter.setOverwriteMode(true);
textFormatter.setAllowsInvalid(false);

If you are going to allow the user to enter decimal values, you should either force the DecimalFormat to contain at least one decimal (#.0###), or allow the value to be invalid setAllowsInvalid(true). Otherwise users may not be able to input decimal values.

NumberFormatter provides slightly different behavior to stringToValue than that of its superclass. If you have specified a Class for values, DefaultFormatter.setValueClass(Class), that is one of of Integer, Long, Float, Double, Byte or Short and the Format's parseObject returns an instance of Number, the corresponding instance of the value class will be created using the constructor appropriate for the primitive type the value class represents. For example: setValueClass(Integer.class) will cause the resulting value to be created via Integer.valueOf(((Number)formatter.parseObject(string)).intValue()). This is typically useful if you wish to set a min/max value as the various Number implementations are generally not comparable to each other. This is also useful if for some reason you need a specific Number implementation for your values.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans has been added to the java.beans package. Please see XMLEncoder.

Since:: 1.4

Constructor Summary

Constructor	Description
`NumberFormatter()`	Creates a `NumberFormatter` with the default `NumberFormat` instance obtained from `NumberFormat.getNumberInstance()`.
`NumberFormatter(NumberFormat format)`	Creates a NumberFormatter with the specified Format instance.

Method Summary

Modifier and Type	Method	Description
`void`	`setFormat(Format format)`	Sets the format that dictates the legal values that can be edited and displayed.

Methods declared in class InternationalFormatter

clone, getActions, getFields, getFormat, getMaximum, getMinimum, install, setMaximum, setMinimum, stringToValue, valueToString

Modifier and Type	Method	Description
`Object`	`clone()`	Creates a copy of the DefaultFormatter.
`protected Action[]`	`getActions()`	If `getSupportsIncrement` returns true, this returns two Actions suitable for incrementing/decrementing the value.
`Format.Field[]`	`getFields(int offset)`	Returns the `Format.Field` constants associated with the text at `offset`.
`Format`	`getFormat()`	Returns the format that dictates the legal values that can be edited and displayed.
`Comparable<?>`	`getMaximum()`	Returns the maximum permissible value.
`Comparable<?>`	`getMinimum()`	Returns the minimum permissible value.
`void`	`install(JFormattedTextField ftf)`	Installs the `DefaultFormatter` onto a particular `JFormattedTextField`.
`void`	`setMaximum(Comparable<?> max)`	Sets the maximum permissible value.
`void`	`setMinimum(Comparable<?> minimum)`	Sets the minimum permissible value.
`Object`	`stringToValue(String text)`	Returns the `Object` representation of the `String` `text`.
`String`	`valueToString(Object value)`	Returns a String representation of the Object `value`.

Methods declared in class DefaultFormatter

getAllowsInvalid, getCommitsOnValidEdit, getDocumentFilter, getNavigationFilter, getOverwriteMode, getValueClass, setAllowsInvalid, setCommitsOnValidEdit, setOverwriteMode, setValueClass

Modifier and Type	Method	Description
`boolean`	`getAllowsInvalid()`	Returns whether or not the value being edited is allowed to be invalid for a length of time.
`boolean`	`getCommitsOnValidEdit()`	Returns when edits are published back to the `JFormattedTextField`.
`protected DocumentFilter`	`getDocumentFilter()`	Returns the `DocumentFilter` used to restrict the characters that can be input into the `JFormattedTextField`.
`protected NavigationFilter`	`getNavigationFilter()`	Returns the `NavigationFilter` used to restrict where the cursor can be placed.
`boolean`	`getOverwriteMode()`	Returns the behavior when inserting characters.
`Class<?>`	`getValueClass()`	Returns that class that is used to create new Objects.
`void`	`setAllowsInvalid(boolean allowsInvalid)`	Sets whether or not the value being edited is allowed to be invalid for a length of time (that is, `stringToValue` throws a `ParseException`).
`void`	`setCommitsOnValidEdit(boolean commit)`	Sets when edits are published back to the `JFormattedTextField`.
`void`	`setOverwriteMode(boolean overwriteMode)`	Configures the behavior when inserting characters.
`void`	`setValueClass(Class<?> valueClass)`	Sets that class that is used to create new Objects.

Methods declared in class JFormattedTextField.AbstractFormatter

getFormattedTextField, invalidEdit, setEditValid, uninstall

Modifier and Type	Method	Description
`protected JFormattedTextField`	`getFormattedTextField()`	Returns the current `JFormattedTextField` the `AbstractFormatter` is installed on.
`protected void`	`invalidEdit()`	This should be invoked when the user types an invalid character.
`protected void`	`setEditValid(boolean valid)`	Invoke this to update the `editValid` property of the `JFormattedTextField`.
`void`	`uninstall()`	Uninstalls any state the `AbstractFormatter` may have installed on the `JFormattedTextField`.

Methods declared in class Object

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

Modifier and Type	Method	Description
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

NumberFormatter

public NumberFormatter()

Creates a NumberFormatter with the default NumberFormat instance obtained from NumberFormat.getNumberInstance().

NumberFormatter

public NumberFormatter(NumberFormat format)

Creates a NumberFormatter with the specified Format instance.

Parameters:: format - Format used to dictate legal values

Method Details

setFormat

public void setFormat(Format format)

Sets the format that dictates the legal values that can be edited and displayed.

If you have used the nullary constructor the value of this property will be determined for the current locale by way of the NumberFormat.getNumberInstance() method.

Overrides:: setFormat in class InternationalFormatter
Parameters:: format - NumberFormat instance used to dictate legal values

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