Notes-Google zxing two-dimensional code, output to the page with Data flow display

notes, Google zxing two-dimensional code, with data flow output to the page display

Two-dimensional code has been very popular, today practiced a bit, requirements are generated for the different parameters of the address link two-dimensional code, and displayed on the page, if the use of generated pictures to save the local return to the relative path, will produce a heap of garbage picture files, but also to remove the late is really trouble, think of the log on the checkout code can directly output to the page , so on the same, less nonsense directly on the code.

Project is Springmvc,maven management
First import Google's two-dimensional code pom file zxing dependencies

  <!--two-dimensional code-->
    <dependency>
      <groupId>com.google.zxing</groupId>
      <artifactid >core</artifactId>
      <version>3.2.0</version>
    </dependency>
    < dependency>
      <groupId>com.google.zxing</groupId>
      <artifactid>javase</artifactid >
      <version>3.2.0</version>
    </dependency>

The page JSP displays the two-dimensional code place:

Java Controller Code

 @RequestMapping (value = "/getq", method = {requestmethod.post, requestmethod.get}) Publ
        IC void Getqcode (HttpServletResponse resp, string id) throws IOException {string url = "Address to generate a two-dimensional code" +ID; if (URL!= null &&! "".
            Equals (URL)) {Servletoutputstream stream = null; try {int width = 200;//picture width int height = 200;//height stream = resp.getoutp
                Utstream ();
                Qrcodewriter writer = new Qrcodewriter ();
                Bitmatrix m = writer.encode (URL, barcodeformat.qr_code, height, width);
            Matrixtoimagewriter.writetostream (M, "PNG", stream);
            catch (Writerexception e) {e.printstacktrace ();
                    finally {if (stream!= null) {Stream.flush ();
                Stream.Close (); }
            }
        }
    }

Finally, when the page loads, it executes the SRC request inside the IMG tag to return to the stream and show it.