The
JAXBContext
provides the JAXB users anchor to
the implmentation and hos generated classes. A JAXBContext is used to
obtain instances of
Marshaller
,
Unmarshaller
, and
Validator
. To obtain a JAXBContext, the
application invokes
JAXBContext context = JAXBContext.newInstance("com.mycompany:com.mycompany.xml");
The list of colon separated package names matches the list in the
schemas used to generate classes. In other words: If you have a
schema using package name "com.mycompany.xml", then this package
name has to be part of the list.
The
JAXBContext
class will scan the given list of packages
for a file called
jaxb.properties. This file contains the
name of an instantiation class in the property
JAXB_CONTEXT_FACTORY
. (See
newInstance(String)
for
details on how the class name is obtained.) Once such a file is found, the
given class is loaded via
ClassLoader.loadClass(java.lang.String)
.
The
JAXBContext
class demands, that the created object
has a method
public static JAXBContext createContext(String pPath, ClassLoader pClassLoader)
throws JAXBException;
This method is invoked with the same path and
ClassLoader
than
above. See
newInstance(String,ClassLoader)
} for details on the choice
of the
ClassLoader
.
The created context will scan the same package path for implementation
specific configuration details (in the case of the
JaxMe
application a file called
Configuration.xml in any of the
packages) and do whatever else is required to initialize the runtime.
In particular it will invoke
DatatypeConverter.setDatatypeConverter(DatatypeConverterInterface)
.
createMarshaller
public abstract Marshaller createMarshaller()
throws JAXBException
Creates a new instance of
Marshaller
. The
Marshaller
can be used
to convert JAXB objects into XML data.
Note: Marshallers are reusable, but not reentrant (thread safe).
createUnmarshaller
public abstract Unmarshaller createUnmarshaller()
throws JAXBException
Creates a new instance of
Unmarshaller
. The
Unmarshaller
can be used
to convert XML data into JAXB objects.
Note: Unmarshallers are reusable, but not reentrant (thread safe).
newInstance
public static JAXBContext newInstance(String pPath,
ClassLoader pClassLoader)
throws JAXBException
Creates a new instance of
JAXBContext
by applying
the following algorithm:
- The first step is to determine the name of an initialization class.
For any of the package names in the list given by
pPath
the JAXBContext
class will try to find a file
called jaxb.properties. This file's got to be in
standard property file format. The JAXBContext
class
will load the property file. - A property called "javax.xml.bind.context.factory" (see
JAXB_CONTEXT_FACTORY
) is evaluated. It must contain the
name of an initialization class. The initialization class is
loaded via
pClassLoader.loadClass(String)
. - The initialization class must contain a method
public static JAXBContext createContext(String, ClassLoader) throws JAXBException;
which is invoked with the parameters pPath
and
pClassLoader
. The result of this method is also
used as the result of the newInstance(String)
method.
pPath
- A colon separated path of package names where to look for
jaxb.properties files. The package names must match the
generated classes which you are going to use in your application.
- An initialized instance of
JAXBContext
.
JAXBException
- An error occurred while creating the JAXBContext instance.
newInstance
public static JAXBContext newInstance(java.lang.String pPath)
throws JAXBException
Creates a new instance of
JAXBContext
by applying
the following algorithm:
- The first step is to determine the name of an initialization class.
For any of the package names in the list given by
pPath
the JAXBContext
class will try to find a file
called jaxb.properties. This file's got to be in
standard property file format. The JAXBContext
class
will load the property file. - A property called "javax.xml.bind.context.factory" (see
JAXB_CONTEXT_FACTORY
) is evaluated. It must contain the
name of an initialization class. The initialization class is
loaded via
Thread.currentThread().getContextClassLoader().loadClass(String)
. - The initialization class must contain a method
public static JAXBContext createContext(String, ClassLoader) throws JAXBException;
which is invoked with the pPath
argument and the
ClassLoader
of the JAXBContext class as
parameters. The result of this method is also used as the
result of the
newInstance(String)
method.
pPath
- A colon separated path of package names where to look for
jaxb.properties files. The package names must match the
generated classes which you are going to use in your application.
- An initialized instance of
JAXBContext
.
JAXBException
- An error occurred while creating the JAXBContext instance.