Hacktoberfest 2026:维护者为十月标记出来的 issue,仍然开放、适合新手。 浏览 Hacktoberfest issue

IllegalArgumentException when painting image while running out of handles

未关闭
#3,443 1 条评论 0 个 reaction 已指派 0 人 在 GitHub 查看

维护者通常 1 天内回复

还没有人认领这个 Issue。

评估

难度
4/5
预计耗时
3-5 天
新手友好度
55/100
Issue 类型
缺陷
描述清晰度
基本清楚
活跃度
冷清
技术栈
java
领域
backend

调研方向

Start in Image.java at the GetDIBits call cited in the issue, then trace how its return value reaches DestroyableImageHandle.getImageData and image painting. Reproduce on Windows with the supplied program or a focused test that exhausts handles. Done means handle exhaustion reports an SWT error such as “No more handles,” rather than an IllegalArgumentException.

由索引模型根据 Issue 内容生成。

描述

Windows

Describe the bug

Trying to paint an image while all available handles have been consumed fails with an IllegalArgumentException instead of an SWTError.

To Reproduce

package gef;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

public class DrawGC2 {

	public static void main(String[] args) {
		Shell shell = new Shell();
		Display display = shell.getDisplay();

		int width = 310;
		int height = 310;

		List<Image> images = new ArrayList<>();
		for (int i = 0; i < 8000; ++i) {
			Image image = new Image(display, width, height);
			GC gc = new GC(image);
			gc.dispose();
			images.add(image);
		}

		shell.addPaintListener(event -> {
			for (Image image : images) {
				event.gc.drawImage(image, 0, 0, width, height, 0, 0, 100, 100);
			}
		});

		shell.open();

		while (!shell.isDisposed()) {
			if (!display.readAndDispatch()) {
				display.sleep();
			}
		}

		images.forEach(Image::dispose);
	}
}

Stacktrace:

Exception in thread "main" java.lang.IllegalArgumentException: Argument not valid
	at org.eclipse.swt.SWT.error(SWT.java:4915)
	at org.eclipse.swt.SWT.error(SWT.java:4849)
	at org.eclipse.swt.SWT.error(SWT.java:4820)
	at org.eclipse.swt.graphics.ImageData.<init>(ImageData.java:439)
	at org.eclipse.swt.graphics.ImageData.<init>(ImageData.java:287)
	at org.eclipse.swt.graphics.Image$DestroyableImageHandle.getImageData(Image.java:3305)
	at org.eclipse.swt.graphics.Image$AbstractImageProviderWrapper.getClosestAvailableImageData(Image.java:2106)
	at org.eclipse.swt.graphics.Image$PlainImageProviderWrapper.loadImageData(Image.java:2388)
	at org.eclipse.swt.graphics.Image$HandleAtSize.getOrCreateImageHandleAtClosestSize(Image.java:254)
	at org.eclipse.swt.graphics.Image$HandleAtSize.lambda$0(Image.java:225)
	at java.base/java.util.Optional.orElseGet(Optional.java:364)
	at org.eclipse.swt.graphics.Image$HandleAtSize.refresh(Image.java:225)
	at org.eclipse.swt.graphics.Image.executeOnImageHandleAtBestFittingSize(Image.java:968)
	at org.eclipse.swt.graphics.GC$DrawScalingImageToImageOperation.draw(GC.java:1240)
	at org.eclipse.swt.graphics.GC$DrawScalingImageToImageOperation.apply(GC.java:1222)
	at org.eclipse.swt.graphics.GC.storeAndApplyOperationForExistingHandle(GC.java:6136)
	at org.eclipse.swt.graphics.GC.drawImage(GC.java:1152)
	at gef.DrawGC2.lambda$0(DrawGC2.java:30)
	at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:272)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:91)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4363)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1217)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1241)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1226)
	at org.eclipse.swt.widgets.Composite.WM_PAINT(Composite.java:1627)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:5021)
	at org.eclipse.swt.widgets.Canvas.windowProc(Canvas.java:336)
	at org.eclipse.swt.widgets.Decorations.windowProc(Decorations.java:1490)
	at org.eclipse.swt.widgets.Shell.windowProc(Shell.java:2446)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:5131)
	at org.eclipse.swt.internal.win32.OS.UpdateWindow(Native Method)
	at org.eclipse.swt.widgets.Decorations.setVisible(Decorations.java:1322)
	at org.eclipse.swt.widgets.Shell.setVisible(Shell.java:2192)
	at org.eclipse.swt.widgets.Shell.open(Shell.java:1334)
	at gef.DrawGC2.main(DrawGC2.java:34)

Expected behavior

SWT should return a proper error message. Ideally an "No more handles" error.

Environment:

  1. Select the platform(s) on which the behavior is seen:
    • All OS
    • Windows
    • Linux
    • macOS

Version since
Only tested on master.

Additional information

I think the problem is that the return value is not validated when calling GetDIBits, for example here:

https://github.com/eclipse-platform/eclipse.platform.swt/blob/725c9485b9e37c3e9bc2993923db02fe15781aec/bundles/org.eclipse.swt/Eclipse%20SWT/win32/org/eclipse/swt/graphics/Image.java#L3254-L3257

From the documentation:

If the function fails, the return value is zero.

Which is the case here, resulting in an "empty" image data, causing the validation error.

主要语言
Java
星标
202
派生
206
平均合并
20 小时 20 分钟
30 天内合并 PR
113

环境准备

  • 没有 Dockerfile 或 Docker Compose 文件
  • 没有 Pull Request 模板
  • 阅读贡献指南

从这里开始

  1. 先读完整个 Issue,再读项目的贡献指南。
  2. 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
  3. Fork 仓库,在一个分支上完成修改。
  4. 提交 Pull Request,并在描述里引用这个 Issue 编号。

eclipse-platform/eclipse.platform.swt 的其他 Issue

查看 eclipse-platform/eclipse.platform.swt 的全部 Issue

相似的 Issue

更多 Java Issue

把新 issue 发到你的邮箱

精选适合新手参与的 GitHub issue 摘要。