nxt.http

Class EncodeQRCode

java.lang.Object

nxt.http.APIServlet.APIRequestHandler

nxt.http.EncodeQRCode

public final class EncodeQRCode
extends APIServlet.APIRequestHandler

The EncodeQRCode API converts a UTF-8 string to a base64-encoded jpeg image of a 2-D QR (Quick Response) code, using the ZXing library.

The output qrCodeBase64 string can be incorporated into an in-line HTML image like this: <img src="data:image/jpeg;base64,qrCodeBase64">

The output qrCodeBase64 can be input to the DecodeQRCode API to recover the original qrCodeData.

Request parameters:

• qrCodeData - A UTF-8 text string.
• width - The width of the output image in pixels, optional.
• height - The height of the output image in pixels, optional.

Notes:

• The output image consists of a centrally positioned square QR code with a size which is an integer multiple of the minimum size, surrounded by sufficient white padding to achieve the requested width/height.
• The default width/height of 0 results in the minimum sized output image, with one pixel per black/white region of the QR code and no extra padding.
• To eliminate padding, the requested width/height must be an integer multiple of the minimum.

Response fields:

• qrCodeBase64 - A base64 string encoding a jpeg image of the QR code.

Method Summary

Modifier and Type	Method and Description
protected boolean	allowRequiredBlockParameters()
protected org.json.simple.JSONStreamAware	processRequest(javax.servlet.http.HttpServletRequest request)
protected boolean	requireBlockchain()
protected boolean	requirePost()

Methods inherited from class nxt.http.APIServlet.APIRequestHandler

getAPITags, getFileParameter, getParameters, isPassword, isTextArea, processRequest, requireFullClient, requirePassword, startDbTransaction

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

processRequest

protected org.json.simple.JSONStreamAware processRequest(javax.servlet.http.HttpServletRequest request)
                                                  throws NxtException

Specified by:

processRequest in class APIServlet.APIRequestHandler

Throws:

NxtException

requirePost

protected final boolean requirePost()

Overrides:

requirePost in class APIServlet.APIRequestHandler

allowRequiredBlockParameters

protected boolean allowRequiredBlockParameters()

Overrides:

allowRequiredBlockParameters in class APIServlet.APIRequestHandler

requireBlockchain

protected boolean requireBlockchain()

Overrides:

requireBlockchain in class APIServlet.APIRequestHandler