XML Parser : How to avoid null pointer exception

Question

when given key is not exist it throws NPE .

String nodeValue = eElement.getElementsByTagName(key).item(0).getTextContent();
    if (nodeValue == null || nodeValue.isEmpty())
        return null;
    return nodeValue;`

Answer 1

Try this

 String nodeValue=null;     
if(eElement!=null && eElement.getElementsByTagName(key)!=null     
 && eElement.getElementsByTagName(key).item(0)!=null ){
 nodeValue = eElement.getElementsByTagName(key).item(0).getTextContent();
}
return nodeValue;

Answer 2

Check if any of the element of your expression is null

String nodeValue = null;
if (eElement != null && eElement.getElementsByTagName(key) != null && eElement.getElementsByTagName(key).length > 0) {
    nodeValue = eElement.getElementsByTagName(key).item(0).getTextContent();
}