Class LookupTable

java.lang.Object

java.awt.image.LookupTable

Direct Known Subclasses:: ByteLookupTable, ShortLookupTable

public abstract class LookupTable extends Object

This abstract class defines a lookup table object. ByteLookupTable and ShortLookupTable are subclasses, which contain byte and short data, respectively. A lookup table contains data arrays for one or more bands (or components) of an image (for example, separate arrays for R, G, and B), and it contains an offset which will be subtracted from the input values before indexing into the arrays. This allows an array smaller than the native data size to be provided for a constrained input. If there is only one array in the lookup table, it will be applied to all bands. All arrays must be the same size.

See Also:

Constructor Summary

LookupTable(int offset,
 int numComponents)

Modifier	Constructor	Description
`protected`	Constructs a new LookupTable from the number of components and an offset into the lookup table.

Method Summary

Modifier and Type	Method	Description
`int`	`getNumComponents()`	Returns the number of components in the lookup table.
`int`	`getOffset()`	Returns the offset.
`abstract int[]`	`lookupPixel(int[] src, int[] dest)`	Returns an `int` array of components for one pixel.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`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

LookupTable

protected LookupTable(int offset, int numComponents)

Constructs a new LookupTable from the number of components and an offset into the lookup table.

Parameters:: offset - the offset to subtract from input values before indexing into the data arrays for this LookupTable; numComponents - the number of data arrays in this LookupTable
Throws:: IllegalArgumentException - if offset is less than 0 or if numComponents is less than 1

Method Details

getNumComponents

public int getNumComponents()

Returns the number of components in the lookup table.

Returns:: the number of components in this LookupTable.

getOffset

public int getOffset()

Returns the offset.

Returns:: the offset of this LookupTable.

lookupPixel

public abstract int[] lookupPixel(int[] src, int[] dest)

Returns an int array of components for one pixel. The dest array contains the result of the lookup and is returned. If dest is null, a new array is allocated. The source and destination can be equal.

Parameters:: src - the source array of components of one pixel; dest - the destination array of components for one pixel, translated with this LookupTable
Returns:: an int array of components for one pixel.

© 1993, 2025, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.