How can I extract ? Please help me.........

Question

First of all, I am very new user to XML and also Java. If my question is nonsense, forgive me, please.
I would like to test that the string in the node are equal with some string that I want to search. I use DOM API.
The following code are ok for the node is directly included text CDATA. The program gives the true value. In the following simple code, I tried to search the string "ACTI".
for example; the node, <LABEL>Problem in Activity</LABEL> , I got "true".
But I would like to match also the node ,
<SLOT label="slot" kind="a/o" role="occurs in" class_constraint="Activity" >
There is also "Activity" string value in class_constraint.
So how can I extract and match that string data?
Help me please!
case Node.CDATA_SECTION_NODE:
System.out.println(node.getNodeValue());
if (node.getNodeValue() != null) {
     String aa = (node.getNodeValue().toUpperCase());
     if ( (aa.indexOf("ACTI") >= 0))
     System.out.println("true");
     else
     System.out.println("false");
<CONCEPT>
<LABEL>Problem in Activity</LABEL>
<SLOTS>
<SLOT label="slot" kind="a/o" role="occurs in" class_constraint="Activity" >
</SLOT>
</SLOTS>
</CONCEPT>

Answer 1

Thank you very much for your help.
I do appreciate your reply.
As I gave my code example in my first post, I parse the XML document and I checked each node whether it is CDATA Node or Document Node, Element Node, and so on.. I used CASE statement.
If it is CDATA node, I compare Node value and the string I want to search.
At that time, I faced the problem that you solved already, I didn't know how to compare in attribute node.
With your suggestion, I can compare now.
But the problem now is that... when I extract element by tag name, it cannot test node by node.
So, how can I combine these two code?
Actually, what I am going to do is that if node is not match (in anywhere) with the string what I want to search starting from parent node to all child nodes, I want to delete that node starting from parent node and it's childs. And I want to create a new XML document by deleating unmatched nodes.
For example, in the following XML, I would like to delete the second <CONCEPT> node while I search for "Acti" string. There is no "Acti" in the second.
<CONCEPT>
<LABEL>Problem in Activity</LABEL>
<SLOTS>
<SLOT label="slot" kind="a/o" role="occurs in" class_constraint="Design" >
<SUB_L label="" def="" role_name="" class_const="Activity" />
</SLOT>
<SLOT label="slot" kind="a/o" role="occurs in" class_constraint="Const" >
<SUB_L class_const="Activity" />
</SLOT>
</SLOTS>
</CONCEPT>
<CONCEPT>
<LABEL>Problem in REQ</LABEL>
<SLOTS>
<SLOT label="slot" kind="a/o" role="occurs in" class_constraint="Req" >
<SUB_L class_const="Change" />
</SLOT>
</SLOTS>
</CONCEPT>