org.apache.paimon.plugin

Class ComponentClassLoader

java.lang.Object

java.lang.ClassLoader

java.security.SecureClassLoader

java.net.URLClassLoader

org.apache.paimon.plugin.ComponentClassLoader

All Implemented Interfaces:

Closeable, AutoCloseable

public class ComponentClassLoader
extends URLClassLoader

A URLClassLoader that restricts which classes can be loaded to those contained within the given classpath, except classes from a given set of packages that are either loaded owner or component-first.

Depiction of the class loader hierarchy:

       Owner     Bootstrap
           ^         ^
           |---------|
                |
            Component
 

For loading classes/resources, class loaders are accessed in one of the following orders:

• component-only: component -> bootstrap; default.
• component-first: component -> bootstrap -> owner; opt-in.
• owner-first: owner -> component -> bootstrap; opt-in.

Constructor Summary

Constructors

Constructor and Description
ComponentClassLoader(URL[] classpath, ClassLoader ownerClassLoader, String[] ownerFirstPackages, String[] componentFirstPackages)

Method Summary

Modifier and Type	Method and Description
URL	getResource(String name)
Enumeration<URL>	getResources(String name)
protected Class<?>	loadClass(String name, boolean resolve)

Methods inherited from class java.net.URLClassLoader

addURL, close, definePackage, findClass, 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, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, 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

Constructor Detail

ComponentClassLoader

public ComponentClassLoader(URL[] classpath,
                            ClassLoader ownerClassLoader,
                            String[] ownerFirstPackages,
                            String[] componentFirstPackages)

Method Detail

loadClass

protected Class<?> loadClass(String name,
                             boolean resolve)
                      throws ClassNotFoundException

Overrides:

loadClass in class ClassLoader

Throws:

ClassNotFoundException

getResource

public URL getResource(String name)

Overrides:

getResource in class ClassLoader

getResources

public Enumeration<URL> getResources(String name)
                              throws IOException

Overrides:

getResources in class ClassLoader

Throws:

IOException