org.jibx.binding

Class Loader

java.lang.Object

java.lang.ClassLoader

java.security.SecureClassLoader

java.net.URLClassLoader

org.jibx.binding.Loader

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

Direct Known Subclasses:

Loader.NondelegatingLoader

public class Loader
extends java.net.URLClassLoader

Binding classloader. This is intended to substitute for the System classloader (i.e., the one used for loading user classes). It first processes one or more binding definitions, caching the binary classes modified by the bindings. It then uses these modified forms of the classes when they're requested for loading.

Author:

Dennis M. Sosnoski

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Loader.NondelegatingLoader Version of bind-on-demand loader which will not delegate handling of classes included in the binding definition.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.ArrayList	m_bindings Binding definitions used by loader.
private java.util.HashMap	m_classMap Map of classes modified by binding.
private boolean	m_isBound Flag for bindings compiled into class code.

Constructor Summary

Constructors

Constructor and Description
Loader() Default constructor.
Loader(java.net.URL[] paths) Constructor with classpath URLs supplied.
Loader(java.net.URL[] paths, java.lang.ClassLoader parent) Constructor with classpath URLs and parent classloader supplied.

Method Summary

Methods

Modifier and Type	Method and Description
protected java.lang.Class	findClass(java.lang.String name) Find and load class by name.
static java.net.URL[]	getClassPaths() Method builds an array of URL for items in the class path.
protected boolean	isBoundClass(java.lang.String name) Check if a class has been modified by a binding.
void	loadBinding(java.lang.String fname, java.lang.String sname, java.io.InputStream is, java.net.URL url) Load binding definition.
void	loadFileBinding(java.lang.String path) Load binding definition from file path.
void	loadResourceBinding(java.lang.String path) Load binding definition from file path.
void	processBindings() Process the binding definitions.
void	reset() Reset loader information.

Methods inherited from class java.net.URLClassLoader

addURL, close, definePackage, findResource, findResources, getPermissions, getResourceAsStream, getURLs, newInstance, newInstance

Methods inherited from class java.security.SecureClassLoader

defineClass, defineClass

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findLibrary, findLoadedClass, findSystemClass, getClassLoadingLock, getPackage, getPackages, getParent, getResource, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, loadClass, loadClass, registerAsParallelCapable, resolveClass, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

m_bindings

private java.util.ArrayList m_bindings

Binding definitions used by loader.

m_isBound

private boolean m_isBound

Flag for bindings compiled into class code.

m_classMap

private java.util.HashMap m_classMap

Map of classes modified by binding.

Constructor Detail

Loader

public Loader(java.net.URL[] paths,
      java.lang.ClassLoader parent)

Constructor with classpath URLs and parent classloader supplied. Sets up the paths for both actual classloading and finding classes to be bound.

Parameters:

paths - array of classpath URLs

parent - classloader used for delegation loading

Loader

public Loader(java.net.URL[] paths)

Constructor with classpath URLs supplied. This uses the supplied classpaths, delegating directly to the parent classloader of the normal System classloader.

Parameters:

paths - array of classpath URLs

Loader

public Loader()
       throws java.net.MalformedURLException

Default constructor. This reads the standard class path and uses it for locating classes used by the binding, delegating directly to the parent classloader of the normal System classloader.

Throws:

java.net.MalformedURLException - on error in classpath URLs

Method Detail

reset

public void reset()

Reset loader information. This discards all prior bindings and clears the internal state in preparation for loading a different set of bindings. It is not possible to clear the loaded classes, though, so any new bindings must refer to different classes from those previously loaded.

getClassPaths

public static java.net.URL[] getClassPaths()
                                    throws java.net.MalformedURLException

Method builds an array of URL for items in the class path.

Returns:

array of classpath URLs

Throws:

java.net.MalformedURLException

loadBinding

public void loadBinding(java.lang.String fname,
               java.lang.String sname,
               java.io.InputStream is,
               java.net.URL url)
                 throws JiBXException,
                        java.io.IOException

Load binding definition. This may be called multiple times to load multiple bindings, but only prior to the bindings being compiled. The reader form of the call is generally preferred, since the document encoding may not be properly interpreted from a stream.

Parameters:

fname - binding definition full name

sname - short form of name to use as the default name of the binding

is - input stream for binding definition document

url - URL for binding definition (null if not available)

Throws:

java.lang.IllegalStateException - if called after bindings have been compiled

java.io.IOException - if error reading the binding

JiBXException - if error in processing the binding definition

loadFileBinding

public void loadFileBinding(java.lang.String path)
                     throws JiBXException,
                            java.io.IOException

Load binding definition from file path. This may be called multiple times to load multiple bindings, but only prior to the bindings being compiled.

Parameters:

path - binding definition file path

Throws:

java.lang.IllegalStateException - if called after bindings have been compiled

java.io.IOException - if error reading the file

JiBXException - if error in processing the binding definition

loadResourceBinding

public void loadResourceBinding(java.lang.String path)
                         throws JiBXException,
                                java.io.IOException

Load binding definition from file path. This may be called multiple times to load multiple bindings, but only prior to the bindings being compiled.

Parameters:

path - binding definition file path

Throws:

java.lang.IllegalStateException - if called after bindings have been compiled

java.io.IOException - if error reading the file

JiBXException - if error in processing the binding definition

processBindings

public void processBindings()
                     throws JiBXException

Process the binding definitions. This compiles the bindings into the classes, saving the modified classes for loading when needed.

Throws:

JiBXException - if error in processing the binding definition

isBoundClass

protected boolean isBoundClass(java.lang.String name)

Check if a class has been modified by a binding. If bindings haven't been compiled prior to this call they will be compiled automatically when this method is called.

Parameters:

name - fully qualified package and class name to be found

Returns:

true if class modified by binding, false if not

findClass

protected java.lang.Class findClass(java.lang.String name)
                             throws java.lang.ClassNotFoundException

Find and load class by name. If the named class has been modified by a binding this loads the modified binary class; otherwise, it just uses the base class implementation to do the loading. If bindings haven't been compiled prior to this call they will be compiled automatically when this method is called.

Overrides:

findClass in class java.net.URLClassLoader

Parameters:

name - fully qualified package and class name to be found

Returns:

the loaded class

Throws:

java.lang.ClassNotFoundException - if the class cannot be found

See Also:

ClassLoader.findClass(java.lang.String)