我试图显示存储在本地磁盘上的图像但没有成功。
在我的 index.xhtml 中，我有：
<h:graphicImage id="image" value="#{tableData.imageTitle}" />
我的 web.xml：
<!-- JSF mapping -->
<servlet>
<servlet-name>Faces Servlet</servlet-name>
<servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.xhtml</url-pattern>
</servlet-mapping>
<!-- Image Mapping -->
<servlet>
<servlet-name>imageServlet</servlet-name>
<servlet-class>package.ImageServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>imageServlet</servlet-name>
<url-pattern>*.png</url-pattern>
</servlet-mapping>
<context-param>
<param-name>javax.faces.PROJECT_STAGE</param-name>
<param-value>Development</param-value>
</context-param>
正如我所说，找不到图像（我的图像存储在“C:\Documents and Settings\user\images”）。
非常感谢任何反馈。谢谢！
更新：
我正在使用嵌入式 Jetty 和 JSF 2.0。
我的 ImageServlet 看起来像这样（我从教程中修改了一点 ImageServlet）：
/*
* The Image servlet for serving from absolute path.
*/
public class ImageServlet extends HttpServlet {
// Constants
// ----------------------------------------------------------------------------------
private static final int DEFAULT_BUFFER_SIZE = 10240; // 10KB.
// Properties
// ---------------------------------------------------------------------------------
private String imagePath;
// Actions
// ------------------------------------------------------------------------------------
public void init() throws ServletException {
// Define base path somehow. You can define it as init-param of the
// servlet.
this.imagePath = "C:\\Documents and Settings\\user\\images";
//this.imagePath = PlatformConfig.getProperty("LocalOperation.Images.Path", null);
System.out.println("imagePath = " + imagePath);
// In a Windows environment with the Applicationserver running on the
// c: volume, the above path is exactly the same as "c:\images".
// In UNIX, it is just straightforward "/images".
// If you have stored files in the WebContent of a WAR, for example in
// the
// "/WEB-INF/images" folder, then you can retrieve the absolute path by:
// this.imagePath = getServletContext().getRealPath("/WEB-INF/images");
}
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// Get requested image by path info.
String requestedImage = request.getPathInfo();
System.out.println("requestedImage = " + requestedImage);
// Check if file name is actually supplied to the request URI.
if (requestedImage == null) {
// Do your thing if the image is not supplied to the request URI.
// Throw an exception, or send 404, or show default/warning image,
// or just ignore it.
response.sendError(HttpServletResponse.SC_NOT_FOUND); // 404.
return;
}
// Decode the file name (might contain spaces and on) and prepare file
// object.
System.out.println(imagePath);
File image = new File(imagePath, URLDecoder.decode(requestedImage,
"UTF-8"));
// Check if file actually exists in filesystem.
if (!image.exists()) {
// Do your thing if the file appears to be non-existing.
// Throw an exception, or send 404, or show default/warning image,
// or just ignore it.
response.sendError(HttpServletResponse.SC_NOT_FOUND); // 404.
return;
}
// Get content type by filename.
String contentType = getServletContext().getMimeType(image.getName());
// Check if file is actually an image (avoid download of other files by
// hackers!).
// For all content types, see:
// http://www.w3schools.com/media/media_mimeref.asp
if (contentType == null || !contentType.startsWith("image")) {
// Do your thing if the file appears not being a real image.
// Throw an exception, or send 404, or show default/warning image,
// or just ignore it.
response.sendError(HttpServletResponse.SC_NOT_FOUND); // 404.
return;
}
// Init servlet response.
response.reset();
response.setBufferSize(DEFAULT_BUFFER_SIZE);
response.setContentType(contentType);
response.setHeader("Content-Length", String.valueOf(image.length()));
response.setHeader("Content-Disposition",
"inline; filename=\"" + image.getName() + "\"");
response.setHeader("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1.
response.setHeader("Pragma", "no-cache"); // HTTP 1.0.
response.setDateHeader("Expires", 0); // Proxies.
// Prepare streams.
BufferedInputStream input = null;
BufferedOutputStream output = null;
try {
// Open streams.
input = new BufferedInputStream(new FileInputStream(image),
DEFAULT_BUFFER_SIZE);
output = new BufferedOutputStream(response.getOutputStream(),
DEFAULT_BUFFER_SIZE);
// Write file contents to response.
byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
int length;
while ((length = input.read(buffer)) > 0) {
output.write(buffer, 0, length);
}
} finally {
// Gently close streams.
close(output);
close(input);
}
}
// Helpers (can be refactored to public utility class)
// ----------------------------------------
private static void close(Closeable resource) {
if (resource != null) {
try {
resource.close();
} catch (IOException e) {
// Do your thing with the exception. Print it, log it or mail
// it.
e.printStackTrace();
}
}
}
}
我的豆子看起来像这样：
@ManagedBean
@SessionScoped
public class TableData {
private String imageTitle = "Image_ON.png";
public String getImageTitle(){
return imageTitle;
}
}
我不明白为什么找不到图像。