编辑:更新了方法
您可以在Java Helper Library中尝试此方法。
或者,这是方法本身:
/**
* This method resizes the given image using Image.SCALE_SMOOTH.
*
* @param image the image to be resized
* @param width the desired width of the new image. Negative values force the only constraint to be height.
* @param height the desired height of the new image. Negative values force the only constraint to be width.
* @param max if true, sets the width and height as maximum heights and widths, if false, they are minimums.
* @return the resized image.
*/
public static Image resizeImage(Image image, int width, int height, boolean max) {
if (width < 0 && height > 0) {
return resizeImageBy(image, height, false);
} else if (width > 0 && height < 0) {
return resizeImageBy(image, width, true);
} else if (width < 0 && height < 0) {
PrinterHelper.printErr("Setting the image size to (width, height) of: ("
+ width + ", " + height + ") effectively means \"do nothing\"... Returning original image");
return image;
//alternatively you can use System.err.println("");
//or you could just ignore this case
}
int currentHeight = image.getHeight(null);
int currentWidth = image.getWidth(null);
int expectedWidth = (height * currentWidth) / currentHeight;
//Size will be set to the height
//unless the expectedWidth is greater than the width and the constraint is maximum
//or the expectedWidth is less than the width and the constraint is minimum
int size = height;
if (max && expectedWidth > width) {
size = width;
} else if (!max && expectedWidth < width) {
size = width;
}
return resizeImageBy(image, size, (size == width));
}
/**
* Resizes the given image using Image.SCALE_SMOOTH.
*
* @param image the image to be resized
* @param size the size to resize the width/height by (see setWidth)
* @param setWidth whether the size applies to the height or to the width
* @return the resized image
*/
public static Image resizeImageBy(Image image, int size, boolean setWidth) {
if (setWidth) {
return image.getScaledInstance(size, -1, Image.SCALE_SMOOTH);
} else {
return image.getScaledInstance(-1, size, Image.SCALE_SMOOTH);
}
}