p:graphicImage 在谷歌浏览器中消失了一段时间

Question

>我在 pf 3.3 的 jsf 2.0 项目中使用了p:graphic image素面的组件。我按照BalusC在这样的问题中解释的那样实现了它。它在Internet Explorer和Firefox上很好，但在谷歌浏览器中，图像消失了，留下了一个损坏的图像链接。

在Internet Explorer中;当我保存为图像时，它被命名为untitled.png，没关系。

在Internet Explorer中;当我保存为图像时，它被命名为dynamiccontent.xhtml.png，没关系。

但是在谷歌浏览器中，它被命名为dynamiccontent.xhtml，即使我更改了扩展名，图像也不可见。

我使用 java 图形库创建图像作为

BufferedImage bufferedimage = new BufferedImage(_width, _height, BufferedImage.TYPE_INT_RGB);
Graphics2D g2d = bufferedimage.createGraphics();
....
g2d.dispose();
ByteArrayOutputStream os = new ByteArrayOutputStream();
ImageIO.write(bufferedimage, "png", os);
return os;

我的 xhtml 是这样的：

<p:graphicImage value="#{imagesBean.image}">
<f:param name="lilw" value="#{reportsLoadSheetBean.loadedIndexLandingWeight}" />
<f:param name="litow" value="#{reportsLoadSheetBean.loadedIndexTakeOffWeight}" />
<f:param name="lizfw" value="#{reportsLoadSheetBean.loadedIndexZeroFuelWeight}" />
<f:param name="tl" value="#{reportsLoadSheetBean.topLimit}" />
<f:param name="zfwf" value="#{reportsLoadSheetBean.zeroFuelWeightForward}" />
<f:param name="zfwa" value="#{reportsLoadSheetBean.zeroFuelWeightAfter}" />
<f:param name="towf" value="#{reportsLoadSheetBean.takeOffWeightForward}" />
<f:param name="towa" value="#{reportsLoadSheetBean.takeOffWeightAfter}" />
<f:param name="lwf" value="#{reportsLoadSheetBean.landingWeightForward}" />
<f:param name="lwa" value="#{reportsLoadSheetBean.landingWeightAfter}" />
<f:param name="width" value="600" />
<f:param name="height" value="200" />
</p:graphicImage>

最后是获取图像并将其发送到接口的应用程序范围的 bean：

public StreamedContent getImage() throws IOException {
FacesContext context = FacesContext.getCurrentInstance();
if (context.getCurrentPhaseId() == PhaseId.RENDER_RESPONSE) {
// So, we're rendering the view. Return a stub StreamedContent so
// that it will generate right URL.
return new DefaultStreamedContent();
} else {
String lilw = context.getExternalContext().getRequestParameterMap().get("lilw");
String litow = context.getExternalContext().getRequestParameterMap().get("litow");
String lizfw = context.getExternalContext().getRequestParameterMap().get("lizfw");
String tl = context.getExternalContext().getRequestParameterMap().get("tl");
String zfwf = context.getExternalContext().getRequestParameterMap().get("zfwf");
String zfwa = context.getExternalContext().getRequestParameterMap().get("zfwa");
String towf = context.getExternalContext().getRequestParameterMap().get("towf");
String towa = context.getExternalContext().getRequestParameterMap().get("towa");
String lwf = context.getExternalContext().getRequestParameterMap().get("lwf");
String lwa = context.getExternalContext().getRequestParameterMap().get("lwa");
List<Number> zeroFuelWeightIntervals = new ArrayList<Number>();
List<Number> takeOffWeightIntervals = new ArrayList<Number>();
List<Number> landingWeightIntervals = new ArrayList<Number>();
zeroFuelWeightIntervals.add(Double.valueOf(zfwf));
zeroFuelWeightIntervals.add(Double.valueOf(zfwa));
zeroFuelWeightIntervals.add(Double.valueOf(tl));
takeOffWeightIntervals.add(Double.valueOf(towf));
takeOffWeightIntervals.add(Double.valueOf(towa));
takeOffWeightIntervals.add(Double.valueOf(tl));
landingWeightIntervals.add(Double.valueOf(lwf));
landingWeightIntervals.add(Double.valueOf(lwa));
landingWeightIntervals.add(Double.valueOf(tl));
int width = Integer.parseInt(context.getExternalContext().getRequestParameterMap().get("width"));
int height = Integer.parseInt(context.getExternalContext().getRequestParameterMap().get("height"));
IdealIntervalPointDiagram diagram = new IdealIntervalPointDiagram(
"ZFL", Double.valueOf(lizfw), zeroFuelWeightIntervals, 
"TOW", Double.valueOf(litow), takeOffWeightIntervals, 
"LAW", Double.valueOf(lilw), landingWeightIntervals,
width, height);
ByteArrayOutputStream os = new ByteArrayOutputStream();
try {
os = diagram.paint();
} catch (IOException e) {
e.printStackTrace();
}
return new DefaultStreamedContent(new ByteArrayInputStream(os.toByteArray()), "image/png");
}

可能是关于素数的错误吗？

Answer 1

我发现了问题。这是关于谷歌浏览器严格检查content-length标题的响应，包括图像，因为服务器压缩图像;实际内容大小与标题上写入的大小不匹配。其他主流浏览器忽略了这种不匹配，但谷歌浏览器没有。 所以我打电话给

FacesContext.getCurrentInstance().getExternalContext().setResponseContentLength(os.size());

在返回图像之前，现在它在谷歌浏览器中也可以正常工作。