JSP 101: How to make a POST and GET method request in JSP

I would like to share with you the GET and POST method request I created while doing some JSP coding.

The example below is a GET method request that will access a specific URL passing the parameters as query string. 


<%@ page language="java" session="false"
import="java.util.*"
import="java.io.*,java.net.*"
%>

<%
try {
        String strLine = "";
        String xmlReturn = "";
       
        URL url = new URL("http://www.example.com/yourscript.jsp?param1=testparam1¶m2=testparam2");

        // read all the text returned by the server
        BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));

        while ((strLine = in.readLine()) != null) {
            xmlReturn += strLine;
        }

        // print out xml return by the server
        out.print(xmlReturn);
        in.close();
} catch (MalformedURLException e) {
} catch (IOException e) {
}

%>


The example below is a POST method request that will access a specific URL passing the parameters in a POST manner.


<%@ page language="java" session="false"
import="java.util.*"
import="java.io.*,java.net.*"
%>

<%
try {
        String strLine = "";
        String xmlReturn = "";

        URL url = new URL("http://www.example.com/yourscript.jsp");

        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setDoOutput(true);
        connection.setRequestMethod("POST");
//      connection.setInstanceFollowRedirects(false);

        DataOutputStream xmlRequest = new DataOutputStream(connection.getOutputStream());
        xmlRequest.writeBytes("param1=testparam1&param2=testparam2");
        xmlRequest.flush();
        xmlRequest.close();

        if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) {
                // server returned HTTP 200 and response okay.

                // read all the text returned by the server
                BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));

                while ((strLine = in.readLine()) != null) {
                    xmlReturn += strLine;
                }


                // print out xml return by the server
                out.print(xmlReturn);
                in.close();
        } else {
                // server returned HTTP error code.
                out.print(connection.getResponseCode());
        }

} catch (MalformedURLException e) {
} catch (IOException e) {
}

%> 


Hope this helps you on your JSP endeavor. Happy coding!!

Quote for the day: The real heart of servanthood is security. Show me someone who thinks he is too important to serve, and I'll show you someone who is basically insecure. How we treat others is really a reflection of how we think of ourselves. - john m.

How to align in center your modal page in jQuery

I have created a jQuery function that will align your modal page in center. The alignment will default to "0" if it encounters a negative value.

Please see below script.

$.fn.doCenter = function () {
    var topVal = (($(window).height() - this.outerHeight()) / 2) + $(window).scrollTop();
    var leftVal = (($(window).width() - this.outerWidth()) / 2) + $(window).scrollLeft();

    if (topVal < 0) topVal = 0;
    if (leftVal < 0) leftVal = 0;

    this.css("position","absolute");
    this.css("top", topVal + "px");
    this.css("left", leftVal + "px");

    return this;
}


Sample usage:

$("#yourmodal").doCenter();


Give it a try, you will love it!!

How to parse an XML return across browser and return an XML object via jQuery.

I came to across to a problem where I can't parse the XML return from the REST URL using jQuery on IE browser.

Since our best friend IE has another way of thinking, I come up with a function that cater all XML parsing (across browser).

The function below parseXMLToObj will accept parameter xmlData, which can either be an object or an XML string.

The function will return the converted XML object which you can use in doing some jQuery stuff.

You can download jQuery from here: http://code.jquery.com/jquery-latest.js


function parseXMLToObj(xmlData) {
        if ($.isXMLDoc(xmlData) || !$.browser.msie || ($.browser.msie && document.documentMode == 9)) {
                return $(xmlData);
        } else {
                var xmlDoc = $.parseXML(xmlData);
                return $(xmlDoc);
        }
}


Sample Usage:

var xmlData = "<results><data>1</data><data>2</data></results>";
parseXMLToObj(xmlData);


Goodluck! Happy coding!!

JS 101: How to get URL parameters from HTML page

Same with PHP or ASP page, HTML will be able to get the query string parameters but not that as easy compare to PHP and ASP.

We can get it by parsing the URL parameters via javascript, and to help you with, I created a script below that does it.

The script will parse and get the "spage" parameter of the HTML page and prompt it via alert dialog box. Sample URL will be.. index.htm?spage=1..

var spage = getUrlParam("spage");
alert(spage);

function getUrlParam(param)
{
    var hash = [];
    var value = '';
    var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
    
    for(var i = 0; i < hashes.length; i++) { 
        hash = hashes[i].split('='); 
        if (hash[0] == param) value = hash[1]; 
    } 

    return value;
}

Hope you like it!!

IE 101: Misalignment of element on IE browsers

In web development, most developers have issues on IE compatibility. One of the problem I encountered are the misalignment of the element in IE browser, specially the IE8.

This is due to the styling you made on alignment. We normally use vertical alignment in CSS to align our element vertically.

Problem here is that the value "text-top" is not working on IE8. Hence, you have to use "top" instead, which is the same behavior with "text-top".

In your CSS entries, instead of using this one:

vertical-align: text-top;

You have to use this one:

vertical-align: top;


Hope this helps.

I'll be posting more of IE issues to help other developers to get through with it. Follow IE 101 for more of IE posts.