不幸的是,这里还没有通用的解决方案。但是检测 ResourceHandler 您可以以官方方式实现这一点(自 JSF 2 起):
public class TestResourceHandler extends ResourceHandlerWrapper {
public static final class TestResource extends Resource {
@Override
public InputStream getInputStream() throws IOException {
return null;
}
@Override
public Map<String, String> getResponseHeaders() {
return new HashMap<>();
}
@Override
public String getRequestPath() {
FacesContext context = FacesContext.getCurrentInstance();
return context.getApplication().getViewHandler().getResourceURL(
context, "/faces" + RESOURCE_IDENTIFIER + "/test.gif?ln=test");
}
@Override
public URL getURL() {
return null;
}
@Override
public boolean userAgentNeedsUpdate(FacesContext context) {
return true;
}
}
private ResourceHandler wrapped;
public TestResourceHandler(ResourceHandler wrapped) {
this.wrapped = wrapped;
}
@Override
public ResourceHandler getWrapped() {
return wrapped;
}
@Override
public Resource createResource(String resourceName, String libraryName) {
if ("test".equals(libraryName))
return new TestResource();
return super.createResource(resourceName, libraryName);
}
@Override
public boolean libraryExists(String libraryName) {
if ("test".equals(libraryName))
return true;
return super.libraryExists(libraryName);
}
@Override
public void handleResourceRequest(FacesContext context) throws IOException {
String library = context.getExternalContext().getRequestParameterMap().get("ln");
if ("test".equals(library)) {
BufferedImage image = ImageIO.read(getClass().getResource("/info.png"));
context.getExternalContext().setResponseContentType("image/gif");
ImageIO.write(image, "gif", context.getExternalContext().getResponseOutputStream());
context.responseComplete();
} else {
wrapped.handleResourceRequest(context);
}
}
}
并在 faces-config.xml 中注册:
<faces-config>
<application>
...
<resource-handler>com.intersult.test.util.TestResourceHandler</resource-handler>
</application>
...
</faces-config>
通过 /faces/javax.faces.resource/test.gif?ln=test 或访问资源
此解决方案既适用于应用程序本身,也适用于基础应用程序 WAR 中包含的任何 JSF 库。