Class | Description |
---|---|
ClassFactory |
Creates new instances of classes.
|
ContextFactory |
This class is responsible for producing RI JAXBContext objects.
|
TODO |
Place holder for TODOs.
|
WellKnownNamespace |
Well-known namespace URIs.
|
Enum | Description |
---|---|
Messages |
Formats error messages.
|
This module provides code that implements JAXBContext
.
Roughly speaking the runtime works like this:
JAXBContextImpl
builds itself by reading the model and
composing unmarshallers and marshallers.
The followings are the interesting pieces inside the runtime.
model
XML I/O
The classes NOT in the com.sun.xml.bind.v2
package (and its subpackages)
are also used by old JAXB 1.0 clients.
"Model" is the portion of the code that represents JAXB-bound types.
The following picture illustrates the relationship among major packages of the binding model.
The core model contracts are all interfaces, and they are parameterized so that they can be used with different reflection libraries. This is necessary, as the model is used:
This portion is used by all three running mode of JAXB. The corresponding base-level implementaion is also parameterized.
The runtime model contract and implementation are used only at the run-time. These packages fix the parameterization to the Java reflection, and also exposes additional functionalities to actually do the unmarshalling/marshalling. These classes have "Runtime" prefix.
Finally XJC has its own implementation of the contract in its own package. This package also fixes the parameterization to its own reflection library.
When you work on the code, it is often helpful to know the layer you are in.
The binding model design roughly looks like the following. For more details, see the javadoc of each component.
Model construction happens inside JAXBContext.newInstance(Class[])
.
It's desirable for this step to be fast and consume less memory,
but it's not too performance sensitive.
Code that implements the unmarshaller and the marshaller OTOH needs to be very carefully written to achieve maximum sustaining performance.
The following picture illustrates how the JAXBContext.newInstance(Class[])
method
triggers activities.
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