如何从Java portlet (JSR-286)中的字节数组下载pdf文件？

byte[] pdfBytes = // 字节数组
InputStream inputStream = new ByteArrayInputStream(pdfBytes);

PortletResponse portletResponse = (PortletResponse) response; // 获取PortletResponse对象
portletResponse.setContentType("application/pdf"); // 设置响应类型为PDF
portletResponse.setProperty("Content-Disposition", "attachment; filename=\"example.pdf\""); // 设置下载文件的名称

OutputStream outputStream = portletResponse.getPortletOutputStream(); // 获取响应输出流
byte[] buffer = new byte[4096];
int bytesRead;
while ((bytesRead = inputStream.read(buffer)) != -1) {
    outputStream.write(buffer, 0, bytesRead);
}
outputStream.flush();
outputStream.close();

public void downloadPDF(ActionRequest request, ActionResponse response) throws IOException {
    byte[] pdfBytes = // 字节数组
    InputStream inputStream = new ByteArrayInputStream(pdfBytes);

    PortletResponse portletResponse = (PortletResponse) response;
    portletResponse.setContentType("application/pdf");
    portletResponse.setProperty("Content-Disposition", "attachment; filename=\"example.pdf\"");

    OutputStream outputStream = portletResponse.getPortletOutputStream();
    byte[] buffer = new byte[4096];
    int bytesRead;
    while ((bytesRead = inputStream.read(buffer)) != -1) {
        outputStream.write(buffer, 0, bytesRead);
    }
    outputStream.flush();
    outputStream.close();
}