colormodel.java

JAVA基本类源代码,大家可以学习学习!

               pixel = sdata[0] & 0xffff;
               length = sdata.length;
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])inData;
               pixel = idata[0];
               length = idata.length;
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        if (length == 1) {
            return getAlpha(pixel);
        }
        else {
            throw new UnsupportedOperationException
                ("This method is not supported by this color model");
        }
    }

    /**
     * Returns the color/alpha components for the specified pixel in the
     * default RGB color model format.  A color conversion is done if
     * necessary.  The pixel value is specified by an array of data
     * elements of type transferType passed in as an object reference.
     * If inData is not a primitive array of type transferType, a
     * <code>ClassCastException</code> is thrown.  An
     * <code>ArrayIndexOutOfBoundsException</code> is
     * thrown if <code>inData</code> is not large enough to hold a pixel
     * value for this <code>ColorModel</code>.
     * The returned value will be in a non pre-multiplied format, i.e. if
     * the alpha is premultiplied, this method will divide it out of the
     * color components (if the alpha value is 0, the color values will be 0).
     * @param inData the specified pixel
     * @return the color and alpha components of the specified pixel.
     * @see ColorModel#getRGBdefault
     */
    public int getRGB(Object inData) {
        return (getAlpha(inData) << 24)
            | (getRed(inData) << 16)
            | (getGreen(inData) << 8)
            | (getBlue(inData) << 0);
    }

    /**
     * Returns a data element array representation of a pixel in this
     * <code>ColorModel</code>, given an integer pixel representation in
     * the default RGB color model.
     * This array can then be passed to the 
     * {@link WritableRaster#setDataElements} method of
     * a {@link WritableRaster} object.  If the pixel variable is 
     * <code>null</code>, a new array will be allocated.  If 
     * <code>pixel</code> is not
     * <code>null</code>, it must be a primitive array of type
     * <code>transferType</code>; otherwise, a
     * <code>ClassCastException</code> is thrown.  An
     * <code>ArrayIndexOutOfBoundsException</code> is thrown if 
     * <code>pixel</code> is
     * not large enough to hold a pixel value for this
     * <code>ColorModel</code>. The pixel array is returned.
     * If this <code>transferType</code> is not supported, a
     * <code>UnsupportedOperationException</code> will be 
     * thrown.  Since <code>ColorModel</code> is an abstract class,
     * any instance is an instance of a subclass.  Subclasses must
     * override this method since the implementation in this abstract
     * class throws an <code>UnsupportedOperationException</code>.
     * @param rgb the integer pixel representation in the default RGB
     * color model
     * @param pixel the specified pixel
     * @return an array representation of the specified pixel in this
     *	<code>ColorModel</code>.
     * @throws ClassCastException if <code>pixel</code>
     *  is not a primitive array of type <code>transferType</code>
     * @throws ArrayIndexOutOfBoundsException if
     *  <code>pixel</code> is not large enough to hold a pixel value
     *  for this <code>ColorModel</code>
     * @throws UnsupportedOperationException if this
     *  method is not supported by this <code>ColorModel</code> 
     * @see WritableRaster#setDataElements
     * @see SampleModel#setDataElements
     */
    public Object getDataElements(int rgb, Object pixel) {
        throw new UnsupportedOperationException
            ("This method is not supported by this color model.");
    }
    
    /**
     * Returns an array of unnormalized color/alpha components given a pixel 
     * in this <code>ColorModel</code>.  The pixel value is specified as
     * an <code>int</code>.  An <code>IllegalArgumentException</code>
     * will be thrown if pixel values for this <code>ColorModel</code> are
     * not conveniently representable as a single <code>int</code> or if
     * color component values for this <code>ColorModel</code> are not
     * conveniently representable in the unnormalized form.
     * For example, this method can be used to retrieve the
     * components for a specific pixel value in a 
     * <code>DirectColorModel</code>.  If the components array is 
     * <code>null</code>, a new array will be allocated.  The
     * components array will be returned.  Color/alpha components are
     * stored in the components array starting at <code>offset</code> 
     * (even if the array is allocated by this method).  An
     * <code>ArrayIndexOutOfBoundsException</code> is thrown if  the
     * components array is not <code>null</code> and is not large
     * enough to hold all the color and alpha components (starting at offset).
     * Since <code>ColorModel</code> is an abstract class,
     * any instance is an instance of a subclass.  Subclasses must   
     * override this method since the implementation in this abstract
     * class throws an <code>UnsupportedOperationException</code>.
     * @param pixel the specified pixel
     * @param components the array to receive the color and alpha
     * components of the specified pixel
     * @param offset the offset into the <code>components</code> array at
     * which to start storing the color and alpha components
     * @return an array containing the color and alpha components of the
     * specified pixel starting at the specified offset.
     * @throws UnsupportedOperationException if this
     *		method is not supported by this <code>ColorModel</code>
     */
    public int[] getComponents(int pixel, int[] components, int offset) {
        throw new UnsupportedOperationException
            ("This method is not supported by this color model.");
    }
    
    /**
     * Returns an array of unnormalized color/alpha components given a pixel
     * in this <code>ColorModel</code>.  The pixel value is specified by
     * an array of data elements of type transferType passed in as an
     * object reference.  If <code>pixel</code> is not a primitive array
     * of type transferType, a <code>ClassCastException</code> is thrown.
     * An <code>IllegalArgumentException</code> will be thrown if color
     * component values for this <code>ColorModel</code> are not
     * conveniently representable in the unnormalized form.
     * An <code>ArrayIndexOutOfBoundsException</code> is
     * thrown if <code>pixel</code> is not large enough to hold a pixel
     * value for this <code>ColorModel</code>.
     * This method can be used to retrieve the components for a specific
     * pixel value in any <code>ColorModel</code>.  If the components
     * array is <code>null</code>, a new array will be allocated.  The
     * components array will be returned.  Color/alpha components are
     * stored in the <code>components</code> array starting at 
     * <code>offset</code> (even if the array is allocated by this
     * method).  An <code>ArrayIndexOutOfBoundsException</code>
     * is thrown if  the components array is not <code>null</code> and is
     * not large enough to hold all the color and alpha components
     * (starting at <code>offset</code>).
     * Since <code>ColorModel</code> is an abstract class,
     * any instance is an instance of a subclass.  Subclasses must   
     * override this method since the implementation in this abstract
     * class throws an <code>UnsupportedOperationException</code>.
     * @param pixel the specified pixel
     * @param components an array that receives the color and alpha
     * components of the specified pixel
     * @param offset the index into the <code>components</code> array at
     * which to begin storing the color and alpha components of the 
     * specified pixel
     * @return an array containing the color and alpha components of the
     * specified pixel starting at the specified offset.
     * @throws UnsupportedOperationException if this
     *		method is not supported by this <code>ColorModel</code>
     */
    public int[] getComponents(Object pixel, int[] components, int offset) {
        throw new UnsupportedOperationException
            ("This method is not supported by this color model.");
    }

    /**
     * Returns an array of all of the color/alpha components in unnormalized
     * form, given a normalized component array.  Unnormalized components
     * are unsigned integral values between 0 and 2<sup>n</sup> - 1, where
     * n is the number of bits for a particular component.  Normalized
     * components are float values between a per component minimum and
     * maximum specified by the <code>ColorSpace</code> object for this
     * <code>ColorModel</code>.  An <code>IllegalArgumentException</code>
     * will be thrown if color component values for this
     * <code>ColorModel</code> are not conveniently representable in the
     * unnormalized form.  If the 
     * <code>components</code> array is <code>null</code>, a new array
     * will be allocated.  The <code>components</code> array will
     * be returned.  Color/alpha components are stored in the 
     * <code>components</code> array starting at <code>offset</code> (even
     * if the array is allocated by this method). An
     * <code>ArrayIndexOutOfBoundsException</code> is thrown if the
     * <code>components</code> array is not <code>null</code> and is not
     * large enough to hold all the color and alpha
     * components (starting at <code>offset</code>).  An
     * <code>IllegalArgumentException</code> is thrown if the
     * <code>normComponents</code> array is not large enough to hold
     * all the color and alpha components starting at
     * <code>normOffset</code>.
     * @param normComponents an array containing normalized components
     * @param normOffset the offset into the <code>normComponents</code> 
     * array at which to start retrieving normalized components
     * @param components an array that receives the components from
     * <code>normComponents</code>
     * @param offset the index into <code>components</code> at which to
     * begin storing normalized components from 
     * <code>normComponents</code>
     * @return an array containing unnormalized color and alpha 
     * components.
     * @throws IllegalArgumentException If the component values for this
     * <CODE>ColorModel</CODE> are not conveniently representable in the
     * unnormalized form.
     * @throws IllegalArgumentException if the length of 
     *          <code>normComponents</code> minus <code>normOffset</code>
     *          is less than <code>numComponents</code>
     * @throws UnsupportedOperationException if the
     *          constructor of this <code>ColorModel</code> called the
     *          <code>super(bits)</code> constructor, but did not 
     *          override this method.  See the constructor, 
     *          {@link #ColorModel(int)}.
     */
    public int[] getUnnormalizedComponents(float[] normComponents,
                                           int normOffset,
                                           int[] components, int offset) {
        // Make sure that someone isn't using a custom color model
        // that called the super(bits) constructor.
        if (colorSpace == null) {
            throw new UnsupportedOperationException("This method is not supported "+
                                        "by this color model.");
        }

        if (nBits == null) {
            throw new UnsupportedOperationException ("This method is not supported.  "+
                                         "Unable to determine #bits per "+
                                         "component.");
        }
        if ((normComponents.length - normOffset) < numComponents) {
            throw new
                IllegalArgumentException(
                        "Incorrect number of components.  Expecting "+
                        numComponents);
        }
        
        if (components == null) {
            components = new int[offset+numComponents];
        }

        if (supportsAlpha && isAlphaPremultiplied) {
            float normAlpha = normComponents[normOffset+numColorComponents];
            for (int i=0; i < numColorComponents; i++) {
                components[offset+i] = (int) (normComponents[normOffset+i]
                                              * ((1<<nBits[i]) - 1)
                                              * normAlpha + 0.5f);
            }
            components[offset+numColorComponents] = (int)
                (normAlpha * ((1<<nBits[numColorComponents]) - 1) + 0.5f);
        }
        else {
            for (int i=0; i < numComponents; i++) {
                components[offset+i] = (int) (normComponents[normOffset+i]
                                              * ((1<<nBits[i]) - 1) + 0.5f);
            }
        }
        
        return components;
    }

    /**
     * Returns an array of all of the color/alpha components in normalized
     * form, given an unnormalized component array.  Unnormalized components
     * are unsigned integral values between 0 and 2<sup>n</sup> - 1, where
     * n is the number of bits for a particular component.  Normalized
     * components are float values between a per component minimum and
     * maximum specified by the <code>ColorSpace</code> object for this
     * <code>ColorModel</code>.  An <code>IllegalArgumentException</code>
     * will be thrown if color component values for this
     * <code>ColorModel</code> are not conveniently representable in the
     * unnormalized form.  If the
     * <code>normComponents</code> array is <code>null</code>, a new array
     * will be allocated.  The <code>normComponents</code> array
     * will be returned.  Color/alpha components are stored in the
     * <code>normComponents</code> array starting at