我正在检索jpg图像并尝试通过流结果返回它。剥离东西，基本上我得到的是;
@Result(name="success",type="stream",params={"contentType","image/jpeg","contentDisposition","inline","allowCaching","false","contentLength","%{streamLength}","inputName","%{imageStream}"})
public class WebcamProxy extends ActionSupport {
private byte[] image;
public String execute() {
return getImage(imageUrl);
}
private String getImage(String urlString) {
url = new URL(urlString);
image = readImage(url);
} catch (MalformedURLException e) {
} catch (IOException e) {
}
return SUCCESS;
}
public int getStreamLength() {
return image.length;
}
public InputStream getImageStream() {
return new ByteArrayInputStream(image);
}
}
调试显示正确填充了byte []图像，并且正在调用getImageStream（）方法。但是我收到了java.lang.IllegalArgumentException：在调用堆栈中找不到名称为[％{imageStream}]的java.io.InputStream。
我做错了什么？
java.lang.IllegalArgumentException: Can not find a java.io.InputStream with the name [%{imageStream}] in the invocation stack. Check the tag specified for this action.
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