How to invoke a web service using JDeveloper (given a WSDL)

How to call a web service from Jdeveloper (provided WSDL file or URL)

Create a New Empty Project

The prefix "jaxb" for element "jaxb:globalBindings" is not bound.

I'm using xjc to compile XML Schema into JAXB objects and the
compiling is fine unless I try to define jaxb bindings. For instance,
if I try adding this code in the schema:

<xs:annotation>
<xs:appinfo>
<jaxb:globalBindings generateIsSetMethod="true">
bindingStyle="modelGroupBinding"
choiceContentProperty="true" >

<xjc:serializable uid="12343"/>
<jaxb:javaType name="short"
xmlType="xs:long"
printMethod="javax.xml.bind.DatatypeConverter.printShort"
parseMethod="javax.xml.bind.DatatypeConverter.parseShort"/>
</jaxb:globalBindings>
</xs:appinfo>
</xs:annotation>

xjc complains with:
[ERROR] The prefix "jaxb" for element "jaxb:globalBindings" is not
bound.

SOLUTION
========

Missing namespace declaration. There should be something like this:
xmlns:jaxb="URI"
Just look for the other namespace definitions (i.e. xmlns:s) and
add the above attribute to the end.

Source : http://www.velocityreviews.com/forums/t137983-problem-in-xjc-with-recognizing-jaxb-prefix.html

xsd:date maps to java.util.Calendar

My schema has an element of type xs:date, which jaxb maps to a java.util.Calendar. If I create a Calendar object with Calendar.getInstance(), it marshalls to "2003-11-24-05:00".

How can I get it to marshall to just "2003-11-24"?

SOLUTION:
Write a converter class (see MyConverter below) and added an annotation/appinfo to the xml schema, also shown below.

public class MyConverter
{
    static final SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
    static public String printCalendar(Calendar c)
    {
        return df.format(c.getTime());
    }

    static public Calendar parseCalendar(String c) throws ParseException
    {
        Date d = df.parse(c);
        Calendar cal = Calendar.getInstance();
        cal.setTime(d);
        return cal; 
    }
}

<xsd:schema ...>
<xsd:annotation>
<xsd:appinfo>
<jaxb:globalBindings 
<jaxb:javaType name="java.util.Calendar" xmlType="xsd:date"
printMethod="MyConverter.printCalendar"
parseMethod="MyConverter.parseCalendar"
/>
</jaxb:globalBindings>
</xsd:appinfo>
</xsd:annotation>
...
</xsd:schema>

Source : https://forums.oracle.com/forums/thread.jspa?threadID=1624090

What's the difference between display: none and visibility: hidden?

Question: What's the difference between display: none and visibility: hidden?
The display: none and visibility: hidden CSS properties appear to be the same thing, but they aren't.

Answer:
These two style properties do two different things.

visibility: hidden hides the element, but it still takes up space in the layout.

display: none removes the element completely from the document. It does not take up any space, even though the HTML for it is still in the source code.

You can see the effect of these style properties on this page. I created three identical swatches of code, and then set the display and visibility properties on two so you can see how they look.

Source: http://webdesign.about.com/od/css/f/blfaqhidden.htm

Removing scriptlets from a JSP

I have read on internet that it is a very bad idea to use scriplets in a JSP.
Even if you need to use scriplets in a JSP, that is most likely because you are doing something in JSP, which should be better handled in a Action class.

So, I am trying to gather few tips, how to convert an existing JSP with scriplet to a JSP without scriplet.

Guys please comment and add more, i'll keep on adding it to the main post :)
There could be multiple ways of doing the same thing, you guys can add your knowledge to this, so that we can come up with a post, that we can re-use.

Most of the help has been taken from http://www.roseindia.net/jstl/jstlcoretags.shtml

You might like to read a discussion on WHY to avoid scriplets

Scriplet code	Without scriplet code
<%=request.getContextPath()%>	${pageContext.request.contextPath}
<%= request.getRequestURI().contains("/events/")%>	${fn:contains(pageContext.request.requestURI, '/events/')}
<%= request.getRequestURI().contains("/events/") ? "class='selected'" : ""%>	${fn:contains(pageContext.request.requestURI, '/events/')? 'class="selected"' : ''}
<% if(request.getRequestURI().contains("/events/")) { %> ... <%}%>	<c:if test="${fn:contains(pageContext.request.requestURI, '/events/')}"> ... </c:if>
<% String s = request.getParameter("text1"); %>	<c:set var="s" value="${param.text1}" >
<% out.println(s);%>	<c:out value="${s}" />
<% if(s.equals("sam")) { out.println("Good Morning...SAM!"); } %>	<c:if test="${s eq 'sam'}"> <c:out value="Good Morning...SAM!" /> </c:if>
<% switch(s) { case 1: out.println("Sunday"); case 2: out.println("Monday"); ... } %>	<c:choose> <c:when test="${s==1}">Sunday </c:when> <c:when test="${s==2}">Monday</c:when> <c:when test="${s==3}">Tuesday</c:when> <c:when test="${s==4}">Wednesday</c:when> <c:when test="${s==5}">Thursday</c:when> <c:otherwise> select between 1 & 5 </c:otherwise> </c:choose>
<% HttpSession session = request.getSession(); out.println( (Questions) session.getAttribute("Questions").getQuestionPaperID()); %>	<c:out value="${sessionScope.Questions.questionPaperID}" />
<%request.getSession().getAttribute("my_var") %>	Can be accessed using JSTL with the sessionScope keyword. To access my_var, call sessionScope.myvar Remember to use sessionScope <c:out value="${sessionScope.my_var}"/>

To make it easier, this link would help you understand the JSTL tags better...

Basic fundas about using float or double

Think again if you are going to use float or double for amount/currency field.

Reason behind this is

Floats have a fixed number of total bits of precision, which must be shared among the integer and fractional parts. If you use more of those bits to store a larger integer portion (123456 vs. just 12), that leaves fewer for the fractional portion (.4 vs. .45678).

Also, you should be aware that since float and double are base-2 formats, rather than base-10, many values that can be represented with a small, finite number of digits in base-10 cannot be stored in a double or float. For instance, it is impossible to store exactly 1/10 (0.1) in a double or float, just as it's impossible to store 1/3 (0.333...) exactly in a finite number of digits in base-10.

Demonstration code:

    public static void main(String args[]) {  
        double d = 1997500.43;  
        String s = "1997500.43";  
        float f = (float) d;  
        System.out.println(f);//1997500.4  
  
        float f3 = Float.parseFloat(s);  
        System.out.println(f3);//1997500.4  
  
        float f4 = Double.valueOf(s).floatValue();  
        System.out.println(f4);//1997500.4  
  
        float f5 = new Double(s).floatValue();  
        System.out.println(f5);//1997500.4  
  
        float xFloat;  
        Double x = new Double("63.8644951");  
        xFloat = x.floatValue();  
        System.out.println(xFloat);// 63.864494  
  
        float xFloat2;  
        Double x2 = new Double("3333263.8644951");  
        xFloat2 = x2.floatValue();  
        System.out.println(xFloat2);// 3333263.8  
}  

Detailed information about floats and doubles is available at : http://www.coderanch.com/t/564234/java/java/Precision-loss-String-Float-double

Best Practices while writing Java code

Usually many of us write the java code in a try-catch block as follows

try
{
       // some code here
}
catch(Exception e)
{
    // log exception here
}

Better way to do it is

try
{
       // some code here
}
catch(Exception e)
{
    // log exception here
}
catch(Throwable ex)
{
     // One must add throwable clause always
     // because in case of some error also, you can
     // log it and see, what error has occured.
}

If you do not add Throwable clause, and in production, some error occurs, Then nothing will be logged in your logs, you may end up breaking your head, why the hell it is not working.

Make it a habit to use try-catch-Throwable in place of try-catch-Exception

Classes not being generated in WEB-INF/classes folder

Posting this on behalf of Vaibhav Garg..

The settings in the Eclipse were perfect to store the output in the output folder as WEB-INF/classes folder. But, still the classes were not being generated in this folder when the code was built. 

Reason:

There were a couple of dependent projects included in the build path. And, there were errors in those projects. Due to this reason, the project was not getting built. And, the error list was huge around 2500 errors in the entire workspace. So, it was difficult to get the exact reason whether the project has some errors or not.

Once the errors in dependent projects were resolved, it got built successfully and the class files got generated in the WEB-INF/classes folder.

How to check which application is using a particular port?

Source : http://oolacola.blogspot.com/2009/04/how-to-find-out-which-application-is.html

Let's say that we are looking for port 80 -- IIS, Apache and other web servers listen in port 80, so when you are having problems starting Apache, this technique will be useful. Here is the command.

C:\>netstat -aon | findstr 80

-a means list all active connections and their ports. -o means include their process IDs. -n means display the port numbers numerically.


The pipe symbol ( | ) means, that instead of the result of netstat being displayed on the screen, feed it's result to the findstr process -- we are looking specifically for the line which has 0.0:80 -- you actually don't need findstr, but I don't want to scroll down and hunt down manually which app is using port 80. You might see something like this.

TCP 0.0.0.0:80 0.0.0.0:0 LISTENING 560

Aha! now we know that process 560 is using port 80 (that last column right there, is the process ID), you could press CTRL-ALT-DEL now to show the process window, and manually look up which app has the process ID 560, or you could enter ..

C:\>tasklist | findstr 560

java.sql.SQLException: ORA-03115: unsupported network datatype or representation

java.sql.SQLException: ORA-03115: unsupported network datatype or representation


I was getting the above exception when I was trying to set a CLOB data in the database using java.

More understanding about this exception can be get from

http://www.coderanch.com/t/302117/JDBC/java/java-sql-SQLException-ORA-unsupported

The mistake I was doing and getting the same exception was
While preparing the PreparedStatement Object, i was passing the query like this

pstmt = conn.prepareStatement(sqlQuery.toString());  

And while executing it, again I was giving the query in the overloaded method.

// Please note that DO NOT USE pstmt.executeUpdate(String) overloaded method   
// That will give you this exception : 
// java.sql.SQLException: ORA-03115: unsupported network datatype or representation
int rowsUpdated = pstmt.executeUpdate();  

Use the executeUpdate method without arguments and not the one with a String argument

After making this change, I didn't get this exception.

Exact root cause is still unknown to me as well.

If someone understands it better, please explain it to me as well.




Also to set the clob data in the database you can use the following

String xml= getXml();   
InputStream is = new ByteArrayInputStream(xml.getBytes());   
pstmt.setAsciiStream(++psCount, is, xml.length()); 

How to fill a increasing values in a column of a table?

How to fill a increasing values in a column of a table?

Lets assume we have a table
Table name : test

Name	Value
Yogesh	0
Yogesh	0
Yogesh	0
Yogesh	0
Yogesh	0
Suresh	0
Suresh	0

Requirement : to insert 1, 2, 3 .... corresponding to values Yogesh

Query to Update :

create sequence seq start with 1 increment by 1;
update test set Value=seq.nextval where Name='Yogesh';
commit;

Output :

Name	Value
Yogesh	1
Yogesh	2
Yogesh	3
Yogesh	4
Yogesh	5
Suresh	0
Suresh	0

Classes in Javascript

Source : >http://www.phpied.com/3-ways-to-define-a-javascript-class/

3 ways to define a JavaScript class

Introduction

JavaScript is a very flexible object-oriented language when it comes to syntax. In this article you can find three ways of defining and instantiating an object. Even if you have already picked your favorite way of doing it, it helps to know some alternatives in order to read other people's code.

It's important to note that there are no classes in JavaScript. Functions can be used to somewhat simulate classes, but in general JavaScript is a class-less language. Everything is an object. And when it comes to inheritance, objects inherit from objects, not classes from classes as in the "class"-ical languages.

1. Using a function

This is probably one of the most common ways. You define a normal JavaScript function and then create an object by using the new keyword. To define properties and methods for an object created using function(), you use the this keyword, as seen in the following example.

function Apple (type) {
    this.type = type;
    this.color = "red";
    this.getInfo = getAppleInfo;
}

// anti-pattern! keep reading...
function getAppleInfo() {
    return this.color + ' ' + this.type + ' apple';
}

To instantiate an object using the Apple constructor function, set some properties and call methods you can do the following:

var apple = new Apple('macintosh');
apple.color = "reddish";
alert(apple.getInfo());

1.1. Methods defined internally

In the example above you see that the method getInfo() of the Apple "class" was defined in a separate function getAppleInfo(). While this works fine, it has one drawback – you may end up defining a lot of these functions and they are all in the "global namespece". This means you may have naming conflicts if you (or another library you are using) decide to create another function with the same name. The way to prevent pollution of the global namespace, you can define your methods within the constructor function, like this:

function Apple (type) {
    this.type = type;
    this.color = "red";
    this.getInfo = function() {
        return this.color + ' ' + this.type + ' apple';
    };
}

Using this syntax changes nothing in the way you instantiate the object and use its properties and methods.

1.2. Methods added to the prototype

A drawback of 1.1. is that the method getInfo() is recreated every time you create a new object. Sometimes that may be what you want, but it's rare. A more inexpensive way is to add getInfo() to the prototype of the constructor function.

function Apple (type) {
    this.type = type;
    this.color = "red";
}

Apple.prototype.getInfo = function() {
    return this.color + ' ' + this.type + ' apple';
};

Again, you can use the new objects exactly the same way as in 1. and 1.1.

2. Using object literals

Literals are shorter way to define objects and arrays in JavaScript. To create an empty object using you can do:

var o = {};

instead of the "normal" way:

var o = new Object();

For arrays you can do:

var a = [];

instead of:

var a = new Array();

So you can skip the class-like stuff and create an instance (object) immediately. Here's the same functionality as described in the previous examples, but using object literal syntax this time:

var apple = {
    type: "macintosh",
    color: "red",
    getInfo: function () {
        return this.color + ' ' + this.type + ' apple';
    }
}

In this case you don't need to (and cannot) create an instance of the class, it already exists. So you simply start using this instance.

apple.color = "reddish";
alert(apple.getInfo());

Such an object is also sometimes called singleton. It "classical" languages such as Java, singleton means that you can have only one single instance of this class at any time, you cannot create more objects of the same class. In JavaScript (no classes, remember?) this concept makes no sense anymore since all objects are singletons to begin with.

3. Singleton using a function

Again with the singleton, eh?

The third way presented in this article is a combination of the other two you already saw. You can use a function to define a singleton object. Here's the syntax:

var apple = new function() {
    this.type = "macintosh";
    this.color = "red";
    this.getInfo = function () {
        return this.color + ' ' + this.type + ' apple';
    };
}

So you see that this is very similar to 1.1. discussed above, but the way to use the object is exactly like in 2.

apple.color = "reddish";
alert(apple.getInfo());

new function(){...} does two things at the same time: define a function (an anonymous constructor function) and invoke it with new. It might look a bit confusing if you're not used to it and it's not too common, but hey, it's an option, when you really want a constructor function that you'll use only once and there's no sense of giving it a name.

You saw three (plus one) ways of creating objects in JavaScript. Remember that (despite the article's title) there's no such thing as a class in JavaScript. Looking forward to start coding using the new knowledge? Happy JavaScript-ing!

Making the input file box readonly in IE

Is it possible to prevent a user from typing in a file input text box in IE? The reason I ask is that if a user enters text that does not look like a file system path (eg. doesn't start with something like c:...) then when the user clicks the submit button nothing will happen.

I would either like to not allow the user to type in the box


SOLUTION

<input 
type="file" 
name="file" 
onKeyDown="this.blur()" 
onContextMenu="return false;">

In IE 7.0 and IE8.0 this fix is not required. As it has already been made readonly by Microsoft. This fix is specifically required for IE 6.0

Invalid set of fields set for XMLGregorianCalendar

Exception in thread "main" java.lang.IllegalStateException: com.sun.org.apache.xerces.internal.jaxp.datatype.XMLGregorianCalendarImpl#getXMLSchemaType() :Invalid set of fields set for XMLGregorianCalendar
 at com.sun.org.apache.xerces.internal.jaxp.datatype.XMLGregorianCalendarImpl.getXMLSchemaType(XMLGregorianCalendarImpl.java:1928)
 at com.sun.org.apache.xerces.internal.jaxp.datatype.XMLGregorianCalendarImpl.toXMLFormat(XMLGregorianCalendarImpl.java:1764)
 at javax.xml.datatype.XMLGregorianCalendar.toString(XMLGregorianCalendar.java:866)

I was getting the above exception when I try to run the following code...

XMLGregorianCalendar tmStamp = new XMLGregorianCalendarImpl();
        tmStamp.setYear(2011);
        tmStamp.setMonth(Calendar.NOVEMBER);
        tmStamp.setDay(30);
        tmStamp.setHour(10);
        tmStamp.setMinute(59); 
        System.out.println(tmStamp.toString());

Solution:
Set the seconds as well

tmStamp.setSeconds(30);

Setting the seconds is mandatory when you set hours and minutes.