Setting Namespace Attributes on an Element

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I'm trying to create an XML document in Java that contains the following Element:

<project xmlns="" 

I know how to create the project Node. I also know how to set the color attribute using

element.setAttribute("color", "blue")

Do I set the xmlns and xmlns:acme attributes the same way using setAttribute() or do I do it in some special way since they are namespace attributes?

I believe that you have to use:

element.setAttributeNS("", "xmlns:acme", "");

Specifying Namespaces for Elements and Attributes, That is, by default if a element or attribute is used without a prefix, it is in no namespace. Second, the definition of an element or attribute can specify the. form​. The Activate, Browse, Dynamic, and Serialize attributes are all optional. If none are present, the <Namespace> element serves only as a container for child elements. If they are present, the <Namespace> element applies runtime reflection policy to all the types in the specified namespace.

I do not think below code will serve the question!


This will create an element as below (using DOM)


So this will not add an namespace attribute to an element. So using DOM we can do something like

Element request = doc.createElement("project");

Attr attr = doc.createAttribute("xmlns");


So it will set the first attribute like below, you can set multiple attributes in the same way

<project xmlns=">

ElementTree: Working with Namespaces and Qualified Names, Here's a simple function that takes a prefix/uri elem.set("xmlns:" + prefix, uri) # fixup all elements in the  Explicitly Setting Namespace Attributes # If you want full control over the serialized output, you can explicitly set the namespace attributes before saving the document. The standard serializer only looks for universal names; element and attribute names that already use prefix:tag notation are passed right through.

The short answer is: you do not create xmlns attributes yourself. The Java XML class library automatically creates those. By default, it will auto-create namespace mappings and will choose prefixes based on some internal algorithm. If you don't like the default prefixes assigned by the Java XML serializer, you can control them by creating your own namespace resolver, as explained in this article:

4.2.4. Setting a Default Namespace with the xmlns Attribute, Setting a Default Namespace with the xmlns Attribute You often know that all the content of a particular element will come from a particular XML application. By setting the value of the disabled attribute to the empty string (""), we are setting disabled to true, which results in the button being disabled. DOM methods dealing with element's attributes: Not namespace-aware, most commonly used methods

You can simply specify the namespace when you create the elements. For example:


Then the java DOM libraries will handle your namespace declarations for you.

XML Namespaces, The xmlns attribute in the first <table> element gives the h: prefix a qualified Defining a default namespace for an element saves us from using prefixes in all  The scope of a declared namespace begins at the element where it is declared and applies to the entire content of that element, unless overridden by another namespace declaration with the same prefix name where, the content of an element is the content between the <opening-tag> and </closing-tag> of that element. A namespace is declared as follows:

The only way that worked for me, in 2019, was using the attr() method:

Element element = doc.createElement("project");

Managing Namespaces in an XML Document, Default namespaces apply to elements only, not to attributes. To use the default namespace, omit the prefix and the colon from the declaration on  First, unless the XML document includes a default namespace or a namespace prefix for every element and attribute that it includes, it is necessary to see the corresponding XML schema. Apart from any imported elements or attributes, any element or attribute is one of the following:

XML Schema: Understanding Namespaces, [Inadvisable]: prefix XmlLibrary begins with 'Xml.' Default Namespace (Not Default Namespaces). It would be painful to repeatedly qualify an element or attribute  A XAML namespace is really an extension of the concept of an XML namespace. The techniques of specifying a XAML namespace rely on the XML namespace syntax, the convention of using URIs as namespace identifiers, using prefixes to provide a means to reference multiple namespaces from the same markup source, and so on.

Namespaces, Any element type or attribute name in an XML namespace can be has a "​default namespace", and this is used with XUL elements all the time. How to use attributes attached to a code element. Attributes act as metadata. Without some outward force, they won't actually do anything. To find and act on attributes, Reflection is generally needed. I won't cover Reflection in-depth in this tutorial, but the basic idea is that Reflection allows you to write code in C# that examines other code.

Configure namespaces - Fonto Editor, This ensures that new elements and attributes are assigned to the correct namespace. A namespace without a prefix is called the 'default namespace'. However, instead of setting the default namespace, this namespace declaration sets the namespace for something called a "namespace prefix". In this case, we have chosen to use the prefix xlink (the second part) since the prefix will be used to tell the user agent about attributes that belong to XLink.

  • There are examples for several programming models:…
  • See also @Jokster's answer: ---… ---