raster.java

JAVA基本类源代码,大家可以学习学习!

    }

    /**
     * Create a compatible WritableRaster with location (minX, minY)
     * and size (width, height) specified by rect, a
     * new SampleModel, and a new initialized DataBuffer.
     * @param rect a <code>Rectangle</code> that specifies the size and
     *        location of the <code>WritableRaster</code>
     * @return a compatible <code>WritableRaster</code> with the specified 
     *         size and location and a new sample model and data buffer.
     * @throws RasterFormatException if <code>rect</code> has width
     *         or height less than or equal to zero, or computing either
     *         <code>rect.x + rect.width</code> or
     *         <code>rect.y + rect.height</code> results in integer
     *         overflow
     * @throws NullPointerException if <code>rect<code> is null
     */
    public WritableRaster createCompatibleWritableRaster(Rectangle rect) {
        if (rect == null) {
            throw new NullPointerException("Rect cannot be null");
        }
        return createCompatibleWritableRaster(rect.x, rect.y,
                                              rect.width, rect.height);
    }

    /**
     * Create a compatible WritableRaster with the specified
     * location (minX, minY) and size (width, height), a
     * new SampleModel, and a new initialized DataBuffer.
     * @param x,&nbsp;y the coordinates of the upper-left corner of
     *        the <code>WritableRaster</code>
     * @param w the specified width of the <code>WritableRaster</code>
     * @param h the specified height of the <code>WritableRaster</code>
     * @return a compatible <code>WritableRaster</code> with the specified 
     *         size and location and a new sample model and data buffer.
     * @throws RasterFormatException if <code>w</code> or <code>h</code>
     *         is less than or equal to zero, or computing either
     *         <code>x + w</code> or
     *         <code>y + h</code> results in integer
     *         overflow
     */
    public WritableRaster createCompatibleWritableRaster(int x, int y,
                                                         int w, int h) {
        WritableRaster ret = createCompatibleWritableRaster(w, h);
        return ret.createWritableChild(0,0,w,h,x,y,null);
    }

    /**
     * Create a Raster with the same size, SampleModel and DataBuffer
     * as this one, but with a different location.  The new Raster
     * will possess a reference to the current Raster, accessible
     * through its getParent() method.
     * 
     * @param childMinX,&nbsp;childMinY coordinates of the upper-left 
     *        corner of the new <code>Raster</code>
     * @return a new <code>Raster</code> with the same size, SampleModel, 
     *         and DataBuffer as this <code>Raster</code>, but with the
     *         specified location.
     * @throws RasterFormatException if  computing either
     *         <code>childMinX + this.getWidth()</code> or
     *         <code>childMinY + this.getHeight()</code> results in integer
     *         overflow
     */
    public Raster createTranslatedChild(int childMinX, int childMinY) {
        return createChild(minX,minY,width,height,
                           childMinX,childMinY,null);
    }

    /**
     * Returns a new Raster which shares all or part of this Raster's
     * DataBuffer.  The new Raster will possess a reference to the
     * current Raster, accessible through its getParent() method.
     *
     * <p> The parentX, parentY, width and height parameters
     * form a Rectangle in this Raster's coordinate space,
     * indicating the area of pixels to be shared.  An error will
     * be thrown if this Rectangle is not contained with the bounds
     * of the current Raster.
     *
     * <p> The new Raster may additionally be translated to a
     * different coordinate system for the plane than that used by the current
     * Raster.  The childMinX and childMinY parameters give the new
     * (x, y) coordinate of the upper-left pixel of the returned
     * Raster; the coordinate (childMinX, childMinY) in the new Raster
     * will map to the same pixel as the coordinate (parentX, parentY)
     * in the current Raster.
     *
     * <p> The new Raster may be defined to contain only a subset of
     * the bands of the current Raster, possibly reordered, by means
     * of the bandList parameter.  If bandList is null, it is taken to
     * include all of the bands of the current Raster in their current
     * order.
     *
     * <p> To create a new Raster that contains a subregion of the current
     * Raster, but shares its coordinate system and bands,
     * this method should be called with childMinX equal to parentX,
     * childMinY equal to parentY, and bandList equal to null.
     *
     * @param parentX,&nbsp;parentY coordinates of the upper-left corner 
     *        in this Raster's coordinates
     * @param width      Width of the region starting at (parentX, parentY)
     * @param height     Height of the region starting at (parentX, parentY).
     * @param childMinX,&nbsp;childMinY coordinates of the upper-left corner 
     *                   of the returned Raster
     * @param bandList   Array of band indices, or null to use all bands
     * @return a new <code>Raster</code>.
     * @exception RasterFormatException if the specified subregion is outside
     *                               of the raster bounds.
     * @throws RasterFormatException if <code>width</code> or
     *         <code>height</code>
     *         is less than or equal to zero, or computing any of
     *         <code>parentX + width</code>, <code>parentY + height</code>,
     *         <code>childMinX + width</code>, or
     *         <code>childMinY + height</code> results in integer
     *         overflow
     */
    public Raster createChild(int parentX, int parentY,
                              int width, int height,
                              int childMinX, int childMinY,
                              int bandList[]) {
        if (parentX < this.minX) {
            throw new RasterFormatException("parentX lies outside raster");
        }
        if (parentY < this.minY) {
            throw new RasterFormatException("parentY lies outside raster");
        }
        if ((parentX + width < parentX) ||
            (parentX + width > this.width + this.minX)) {
            throw new RasterFormatException("(parentX + width) is outside raster");
        }
        if ((parentY + height < parentY) ||
            (parentY + height > this.height + this.minY)) {
            throw new RasterFormatException("(parentY + height) is outside raster");
        }

        SampleModel subSampleModel;
        // Note: the SampleModel for the child Raster should have the same
        // width and height as that for the parent, since it represents
        // the physical layout of the pixel data.  The child Raster's width
        // and height represent a "virtual" view of the pixel data, so
        // they may be different than those of the SampleModel.
        if (bandList == null) {
            subSampleModel = sampleModel;
        } else {
            subSampleModel = sampleModel.createSubsetSampleModel(bandList);
        }

        int deltaX = childMinX - parentX;
        int deltaY = childMinY - parentY;

	return new Raster(subSampleModel, dataBuffer,
			  new Rectangle(childMinX, childMinY, width, height),
			  new Point(sampleModelTranslateX + deltaX,
				    sampleModelTranslateY + deltaY), this);
    }

    /**
     * Returns the bounding Rectangle of this Raster. This function returns
     * the same information as getMinX/MinY/Width/Height.
     * @return the bounding box of this <code>Raster</code>.
     */
    public Rectangle getBounds() {
        return new Rectangle(minX, minY, width, height);
    }

    /** Returns the minimum valid X coordinate of the Raster.
     *  @return the minimum x coordinate of this <code>Raster</code>.
     */
    final public int getMinX() {
        return minX;
    }

    /** Returns the minimum valid Y coordinate of the Raster. 
     *  @return the minimum y coordinate of this <code>Raster</code>.
     */
    final public int getMinY() {
        return minY;
    }

    /** Returns the width in pixels of the Raster.  
     *  @return the width of this <code>Raster</code>.
     */
    final public int getWidth() {
        return width;
    }

    /** Returns the height in pixels of the Raster.  
     *  @return the height of this <code>Raster</code>.
     */
    final public int getHeight() {
        return height;
    }

    /** Returns the number of bands (samples per pixel) in this Raster. 
     *  @return the number of bands of this <code>Raster</code>.
     */
    final public int getNumBands() {
        return numBands;
    }

    /** 
     *  Returns the number of data elements needed to transfer one pixel
     *  via the getDataElements and setDataElements methods.  When pixels
     *  are transferred via these methods, they may be transferred in a
     *  packed or unpacked format, depending on the implementation of the
     *  underlying SampleModel.  Using these methods, pixels are transferred
     *  as an array of getNumDataElements() elements of a primitive type given
     *  by getTransferType().  The TransferType may or may not be the same
     *  as the storage data type of the DataBuffer.
     *  @return the number of data elements.
     */
    final public int getNumDataElements() {
        return sampleModel.getNumDataElements();
    }

    /** 
     *  Returns the TransferType used to transfer pixels via the
     *  getDataElements and setDataElements methods.  When pixels
     *  are transferred via these methods, they may be transferred in a
     *  packed or unpacked format, depending on the implementation of the
     *  underlying SampleModel.  Using these methods, pixels are transferred
     *  as an array of getNumDataElements() elements of a primitive type given
     *  by getTransferType().  The TransferType may or may not be the same
     *  as the storage data type of the DataBuffer.  The TransferType will
     *  be one of the types defined in DataBuffer.
     *  @return this transfer type.
     */
    final public int getTransferType() {
        return sampleModel.getTransferType();
    }

    /** Returns the DataBuffer associated with this Raster. 
     *  @return the <code>DataBuffer</code> of this <code>Raster</code>.
     */
    public DataBuffer getDataBuffer() {
        return dataBuffer;
    }

    /** Returns the SampleModel that describes the layout of the image data. 
     *  @return the <code>SampleModel</code> of this <code>Raster</code>.
     */
    public SampleModel getSampleModel() {
        return sampleModel;
    }

    /**
     * Returns data for a single pixel in a primitive array of type
     * TransferType.  For image data supported by the Java 2D(tm) API, 
     * this will be one of DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, 
     * DataBuffer.TYPE_INT, DataBuffer.TYPE_SHORT, DataBuffer.TYPE_FLOAT,
     * or DataBuffer.TYPE_DOUBLE.  Data may be returned in a packed format,
     * thus increasing efficiency for data transfers.
     * An ArrayIndexOutOfBoundsException may be thrown
     * if the coordinates are not in bounds.  However, explicit bounds
     * checking is not guaranteed.
     * A ClassCastException will be thrown if the input object is non null
     * and references anything other than an array of TransferType.
     * @see java.awt.image.SampleModel#getDataElements(int, int, Object, DataBuffer)
     * @param x,&nbsp;y    the coordinates of the pixel location
     * @param outData  An object reference to an array of type defined by
     *                 getTransferType() and length getNumDataElements(). 
     *                 If null, an array of appropriate type and size will be
     *                 allocated
     * @return         An object reference to an array of type defined by
     *                 getTransferType() with the requested pixel data.
     *
     * @throws ArrayIndexOutOfBoundsException if the coordinates are not
     * in bounds, or if outData is too small to hold the output.
     */
    public Object getDataElements(int x, int y, Object outData) {
        return sampleModel.getDataElements(x - sampleModelTranslateX,
                                           y - sampleModelTranslateY,
                                           outData, dataBuffer);
    }

    /**
     * Returns the pixel data for the specified rectangle of pixels in a
     * primitive array of type TransferType.
     * For image data supported by the Java 2D API, this
     * will be one of DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT,
     * DataBuffer.TYPE_INT, DataBuffer.TYPE_SHORT, DataBuffer.TYPE_FLOAT,
     * or DataBuffer.TYPE_DOUBLE.  Data may be returned in a packed format,
     * thus increasing efficiency for data transfers.
     * An ArrayIndexOutOfBoundsException may be thrown
     * if the coordinates are not in bounds.  However, explicit bounds
     * checking is not guaranteed.
     * A ClassCastException will be thrown if the input object is non null
     * and references anything other than an array of TransferType.
     * @see java.awt.image.SampleModel#getDataElements(int, int, int, int, Object, DataBuffer)
     * @param x,&nbsp;y   the coordinates of the upper-left pixel location
     * @param w    Width of