What is the use of JAXB?
JAXB stands for Java Architecture for XML Binding. It provides mechanism to marshal (write) java objects into XML and unmarshal (read) XML into object. Simply, you can say it is used to convert java object into xml and vice-versa. Features of JAXB 2.0
What is the difference between JAX-WS and JAXB?
JAX-WS is an abbreviation for Java API for XML Web Services and is a Java Programming API for creating web services (Especially for SOAP services) and is part of Java EE Platform. JAXB is an abbreviation for Java Architecture for XML Binding. This is used to convert XML to Java object and Java object to XML.
What is the JAXB API for XML binding?
Now developers have another Java API at their disposal that can make it easier to access XML documents: Java Architecture for XML Binding (JAXB). A Reference Implementation of the API is now available in the Java Web Services Developer Pack V 1.1. Let's look at JAXB in action, and compare it to SAX and DOM-based processing.
What are JAXB annotations in Java?
3. JAXB Annotations JAXB uses Java annotations for augmenting the generated classes with additional information. Adding such annotations to existing Java classes prepares them for the JAXB runtime. Let's first create a simple Java object to illustrate marshalling and unmarshalling:
Why is JAXB used?
JAXB simplifies access to an XML document from a Java program by presenting the XML document to the program in a Java format. The first step in this process is to bind the schema for the XML document into a set of Java classes that represents the schema.
What is JAXB and what are its advantages and disadvantages?
JAXB stands for Java architecture for XML binding.It is used to convert XML to java object and java object to XML. JAXB defines an API for reading and writing Java objects to and from XML documents. Unlike SAX and DOM,we don't need to be aware of XML parsing techniques.
How do I work for JAXB?
Let's see the steps to convert java object into XML document.Create POJO or bind the schema and generate the classes.Create the JAXBContext object.Create the Marshaller objects.Create the content tree by using set methods.Call the marshal method.
Is JAXB a framework?
The JAXB binding framework is implemented in three Java packages: The javax. xml. bind package defines abstract classes and interfaces that are used directly with content classes.
What is the difference between Jackson and JAXB?
JAXB converts XML to java objects, and Jackson converts the same java objects to JSON.
What are the three modes in which Castor XML can be used?
To (un-)marshal data to and from XML, Castor XML can be used in one of three modes: introspection mode. mapping mode. descriptor mode (aka generation mode)
What can I use instead of JAXB?
XOM, JDOM, dom4j, etc. etc. Projects like Castor and Apache XMLBeans predate JAXB, so you could have a look at those. Ulf Dittmer wrote: XOM, JDOM, dom4j, etc.
Why was JAXB removed?
JAXB was integrated within the JVM itself, so you didn't need to add any code dependency to have the functionality within your application. But with the modularization performed in JDK 9, it was removed as the maintainers wanted to have a smaller JDK distribution that only contains the core concepts.
What is a JAXB element?
public class JAXBElement
Is JAXB open source?
In 2006 JAXB 2.0 was released under JSR 222 and Maintenance Release 2 released in December 2009. Reference implementations for these specifications were available under the CDDL open source license at java.net.
What is XSD full form?
The full form of XSD is XML Schema Definition. XSD is a way to formally describe the structure and elements in an XML (Extensible Markup Language) document. The purpose of XSD is to define the legal building blocks that relate to an XML document.
What are XSD files?
XML Schema Definition or XSD is a recommendation by the World Wide Web Consortium (W3C) to describe and validate the structure and content of an XML document. It is primarily used to define the elements, attributes and data types the document can contain.
Why was JAXB removed?
JAXB was integrated within the JVM itself, so you didn't need to add any code dependency to have the functionality within your application. But with the modularization performed in JDK 9, it was removed as the maintainers wanted to have a smaller JDK distribution that only contains the core concepts.
What is a JAXB class?
The JAXB class generator for Java generates the interfaces and the implementation classes corresponding to an XML Schema. Its principal advantage to Java developers is automation of the mapping between XML documents and Java code, which enables programs to use generated code to read, manipulate, and re-create XML data.
What can I use instead of JAXB?
XOM, JDOM, dom4j, etc. etc. Projects like Castor and Apache XMLBeans predate JAXB, so you could have a look at those. Ulf Dittmer wrote: XOM, JDOM, dom4j, etc.
What is JAXB marshalling and Unmarshalling?
JAXB definitions Marshalling is the process of transforming Java objects into XML documents. Unmarshalling is the process of reading XML documents into Java objects. The JAXBContext class provides the client's entry point to the JAXB API. It provides API for marshalling, unmarshalling and validating.
What is JAXB used for?
The JAXB utilities will create the hierarchy of data structures for manipulating that XML. JAXB can then be used to read an XML file, and then create instances of the generated classes - laden with the data from your XML. JAXB also does the reverse: takes java classes, and generates the corresponding XML. I like JAXB because it is easy ...
Why do we need JAXB?
Why XML? Because XML is considered light weight option to exchange message on Networks with limited resources. So often we need to convert these XML documents into objects and vice versa. E.g: Simple Java POJO Employee can be used to send Employee data to remote component ( also a Java programme).
How to work with XML?
One needs a way to take an XML file - which is basically a text file - and convert it into some sort of data structure, which your program can then manipulate. JAXB will take an XML Schema that you write and create a set of classes that correspond to that schema.
Why is XML considered light weight?
Because XML is considered light weight option to exchange message on Networks with limited resources. So often we need to convert these XML documents into objects and vice versa. E.g: Simple Java POJO Employee can be used to send Employee data to remote component ( also a Java programme).
What are some alternatives to XML serialization?
There are also some simpler XML serialization libraries like XStream, Digester or XMLBeans that might be alternatives.
Why do I like JAXB?
I like JAXB because it is easy to use, and comes with Java 1.6 (if you are using 1.5, you can download the JAXB .jars.) The way it creates the class hierarchy is intuitive, and in my experience, does a decent job abstracting away the "XML" so that I can focus on "data".
Why not use jibx?
Here's a reason not to use it: performance suffers. There is a good deal of overhead when marshaling and unmarshaling. You might also want to consider another API for XML-Object binding -- such as JiBX: http://jibx.sourceforge.net/
How does JAXB work?
JAXB simplifies access to an XML document from a Java program by presenting the XML document to the program in a Java format. The first step in this process is to bind the schema for the XML document into a set of Java classes that represents the schema.
What is a JAXBContext object?
Create a JAXBContext object. This object provides the entry point to the JAXB API. When you create the object, you need to specify a context path. This is a list of one or more package names that contain interfaces generated by the binding compiler. By allowing multiple package names in the context path, JAXB allows you to unmarshal a combination of XML data elements that correspond to different schemas.
What is an unmarshalling XML document?
Unmarshalling an XML document means creating a tree of content objects that represents the content and organization of the document. The content tree is not a DOM-based tree. In fact, content trees produced through JAXB can be more efficient in terms of memory use than DOM-based trees.
What is schema in XML?
Schema: A schema is an XML specification that governs the allowable components of an XML document and the relationships between the components. For example, a schema identifies the elements that can appear in an XML document, in what order they must appear, what attributes they can have, and which elements are subordinate (that is, are child elements) to other elements. An XML document does not have to have a schema, but if it does, it must conform to that schema to be a valid XML document. JAXB requires that the XML document you want to access has a schema, and that schema is written in the W3C XML Schema Language (see the box "Why W3C XML Schema Language?").
Why is XML and Java important?
That's because XML has emerged as the standard for exchanging data across disparate systems, and Java technology provides a platform for building portable applications. This partnership is particularly important for Web services, which promise users and application developers program functionality on demand from anywhere to anywhere on the Web. XML and Java technology are recognized as ideal building blocks for developing Web services and applications that access Web services.
What is XML and Java?
XML and Java technology are recognized as ideal building blocks for developing Web services and applications that access Web services. A new Java API called Java Architecture for XML Binding (JAXB) can make it easier to access XML documents from applications written in the Java programming language. Java developers can invoke a SAX ...
What is DOM parsing?
In the DOM approach, the parser creates a tree of objects that represents the content and organization of data in the document. In this case, the tree exists in memory. The application can then navigate through the tree to access the data it needs, and if appropriate, manipulate it.
What is JAX-WS in Java?
JAX-WS is an abbreviation for Java API for XML Web Services and is a Java Programming API for creating web services (Especially for SOAP services) and is part of Java EE Platform.
What is web service built?
Web Service built is going to take the input from the client and retrieve the account details like account number, balance and returns along with the customer name in the response. (Note: We are trying to play with a simple service and so values are hard-coded for the account details).
Where can I download NetBeans IDE?
For this article I am using NetBeans IDE and you can download it free from https://netbeans.org/downloads/
What is XML schema?
XML Schema is a widely accepted standard that is not tied to a specific programming language. By using XML schema and providing it to your clients you make your Restful Web Service easier to consume. Your clients have a standardised specification of exactly what they need to send.
Is JSON better than XML?
JSON is much more forgiving than XML is, which makes it simpler to work with. While XML may be old school, it still can be good to use. Even when you’re doing JSON based Restful web services.
Does Spring Source use JAXB?
As a Spring Source consultant, I was at a large company which built a number of Restful APIs. The team building the APIs did not use JAXB to generate classes from an XML Schema. Rather they built the JAXB classes by hand and could not offer their clients an XML Schema. As a consumer of their APIs, it was a time-consuming process to configure and troubleshoot my data types.
Is XML good for programming?
All the ‘experts’ said you had to be using XML for data exchange. XML does have many benefits. But often when programming today, XML is looked as ‘old school’ or too restrictive. XML sure can be finicky to work with. Many developers, when given a choice (including myself), will use JSON over XML. JSON is much more forgiving than XML is, which makes it simpler to work with.
What is JAXB in Java?
JAXB provides a fast and convenient way to marshal (write) Java objects into XML and un-marshal (read) XML into objects. It supports a binding framework that maps XML elements and attributes to Java fields and properties using Java annotations.
What is a JAXB binding compiler?
The same plugin uses the JDK-supplied tool Schemagen. This is a JAXB Binding compiler tool that can generate an XSD schema from Java classes. In order for a Java Class to be eligible for an XSD schema candidate, the class must be annotated with a @XmlType annotation.
What is XML binding plugin?
This plugin uses the Java API for XML Binding (JAXB), version 2+, to generate Java classes from XML Schemas (and optionally binding files) or to create XML schema from an annotated Java class.
What is a bind.jaxbcontext?
The javax.xml.bind.JAXBContext class provides a client's entry point to JAXB API. By default, JAXB does not format the XML document. This saves space and prevents that any white-space may accidentally be interpreted as significant.
How to format JAXB output?
To have JAXB format the output we simply set the Marshaller.JAXB_FORMATTED_OUTPUT property to true on the Marshaller. The marshal method uses an object and an output file where to store the generated XML as parameters.
Why use annotations in Java?
JAXB uses Java annotations for augmenting the generated classes with additional information. Adding such annotations to existing Java classes prepares them for the JAXB runtime.
Where are Java classes generated?
By default, these Java Classes are generated in the target/generated-resources/jaxb folder . We may change the output directory by adding an outputDirectory element to the plugin configuration. We may also add a clearOutputDir element with a value of false to prevent the files in this directory from being erased.
Restful Web Services in Spring
I’m not going to cover building Restful Web Services in Spring in this post. That’s a future topic. But when you’re using Spring MVC to develop Restful Web Services, you can set up a lot of flexibility. I typically design my web services so the client can use JSON or XML. The standards support this, and it’s fairly easy to do.
JAXB Generated Classes for Restful Web Services
In this post, I’m going to show you how to setup a Maven project to create a Jar file of Java classes generated by JAXB from an XML Schema.
Conclusion
This is just a very simple example of generating classing from an XML Schema using JAXB and Maven. In this post, I’ve shown you step by step how to use an XML Schema and JAXB to generate Java classes. The generated classes are bundled into a JAR file, which is portable and can be shared with other Java projects.
