> The `BufferedImage` Javadoc does not mention any constraint about the data 
> type. In practice, `BufferedImage` with floating point values can be rendered 
> by Java2D as well as integers, provided that a compatible `ColorModel` was 
> supplied at construction time. However calls to `setData(Raster)` 
> unexpectedly cast floating point values to integers. For example sample value 
> 0.8 become 0. This is demonstrated by the `SetData` test case in this pull 
> request.
> 
> An easy fix, which is proposed in this pull request, is to replace the whole 
> `BufferedImage.setData(Raster)` method body by a simple call to 
> `WritableRaster.setRect(Raster)`, which handles all `DataBuffer` types 
> correctly. The method contracts documented in their respective Javadoc are 
> compatible. Furthermore an examination of their source code shows that they 
> are equivalent, except for the differences noted in the _Behavioural changes_ 
> section below.
> 
> # Source code comparison
> For demonstrating that delegating to `WritableRaster.setRect(Raster)` would 
> be equivalent to the current code, one can copy the method body and apply the 
> following changes:
> 
> * Remove `dx` parameter, replaced by 0.
> * Remove `dy` parameter, replaced by 0.
> * Rename `srcRaster` parameter as `r` (like in `BufferedImage`).
> * Rename `startY` variable as `i` (like in `BufferedImage`).
> * Rename `srcOffX` variable as `startX` (like in `BufferedImage`).
> * Rename `srcOffY` variable as `startY` (like in `BufferedImage`).
> * Replace `this.minX` by 0 and simplify.
> * Replace `this.minY` by 0 and simplify.
> * Remove the `switch` statement, keeping only the `TYPE_INT` case.
> 
> Then compare with `BufferedImage.setData(Raster)`. The modified block of code 
> from `WritableRaster` is:
> 
> 
> int width  = r.getWidth();
> int height = r.getHeight();
> int startX = r.getMinX();
> int startY = r.getMinY();
> 
> We can see that above code is identical to `BufferedImage`. The next modified 
> block of code from `WritableRaster`:
> 
> 
> int dstOffX = startX;
> int dstOffY = startY;
> 
> // Clip to this raster
> if (dstOffX < 0) {
>     width += dstOffX;
>     startX -= dstOffX;    // = 0 because dstOffX == startX
>     dstOffX = 0;
> }
> if (dstOffY < 0) {
>     height += dstOffY;
>     startY -= dstOffY;    // = 0 because dstOffY == startY
>     dstOffY = 0;
> }
> if (dstOffX+width > this.width) {
>     width = this.width - dstOffX;
> }
> if (dstOffY+height > this.height) {
>     height = this.height - dstOffY;
> }
> if (width <= 0 || height <= 0) {
>     return;
> }
> 
> 
> Above is equivalent to the following code from `BufferedImage`, ex...

Martin Desruisseaux has updated the pull request incrementally with one 
additional commit since the last revision:

  Update copyright years.

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/13797/files
  - new: https://git.openjdk.org/jdk/pull/13797/files/65eb0072..5d69f631

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13797&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13797&range=00-01

  Stats: 3 lines in 3 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/13797.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13797/head:pull/13797

PR: https://git.openjdk.org/jdk/pull/13797

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