html - checking if a bean is null using javascript or other methods - Stack Overflow

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The below code snippets work when the values used to create myBean is not null.

How do I take care of the scenario when myBean has null value? Is there a way to check the bean's value?

<bean:define id="myBean" name="<%=myName%>" property="<%=myProp%>"/>

now if myName and/or myProp is null,

Error javax.servlet.jsp.JspException: Define tag cannot set a null value error.

Attempted solution:

<c:if test="${not empty myBean}">
            <bean:define id="myBean" name="<%=myName%>" property="<%=myProp%>"/>
            </c:if>

The below code snippets work when the values used to create myBean is not null.

How do I take care of the scenario when myBean has null value? Is there a way to check the bean's value?

<bean:define id="myBean" name="<%=myName%>" property="<%=myProp%>"/>

now if myName and/or myProp is null,

Error javax.servlet.jsp.JspException: Define tag cannot set a null value error.

Attempted solution:

<c:if test="${not empty myBean}">
            <bean:define id="myBean" name="<%=myName%>" property="<%=myProp%>"/>
            </c:if>

• javascript
• html
• jsp
• struts

Share Improve this question Follow edited Oct 4, 2013 at 19:59 bouncingHippo asked Oct 4, 2013 at 19:15 bouncingHippobouncingHippo 6,0402323 gold badges7171 silver badges110110 bronze badges 3

• what doesn't work ? You mean you get a js var myBean value as 'null' string and you want to avoid that ? – Ash Commented Oct 4, 2013 at 19:19
• edited, sorry if i wasn't clear – bouncingHippo Commented Oct 4, 2013 at 19:23
• Hi [this link][1] will bw helpful.This is just a guess [1]: stackoverflow./a/14648106/1069633 – Saurabh Ande Commented Oct 4, 2013 at 19:29

Add a ment  | 

2 Answers 2

Sorted by: Reset to default 3

@bouncingHippo Use struts logic tag for this null checking purpose. Like,

<logic:present name="<%=myName%>" property="<%=myProp%>">
   <bean:define id="myBean" name="<%=myName%>" property="<%=myProp%>"/>
</logic:present>

Let me know if this helps..

EDITED as per additional information provided:

<c:if test="${not empty myName}">
... your bean def
</c:if> 

Ignore: or maybe something like this: ${empty myBean} or ${not empty myBean} ??

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