Package net.minestom.server.extras.selfmodification

Class HierarchyClassLoader

java.lang.Object

java.lang.ClassLoader

java.security.SecureClassLoader

java.net.URLClassLoader

net.minestom.server.extras.selfmodification.HierarchyClassLoader

All Implemented Interfaces:

Closeable, AutoCloseable

Direct Known Subclasses:

MinestomExtensionClassLoader, MinestomRootClassLoader

public abstract class HierarchyClassLoader
extends URLClassLoader

Classloader part of a hierarchy of classloader.

Field Summary

Fields

Modifier and Type	Field	Description
protected final List<MinestomExtensionClassLoader>	children
protected final List<HierarchyClassLoader>	parents

Constructor Summary

Constructors

Constructor	Description
HierarchyClassLoader(String name, URL[] urls, ClassLoader parent)

Method Summary

Modifier and Type	Method	Description
void	addChild(@NotNull MinestomExtensionClassLoader loader)
String	findLibrary(String libname)
String	getName()
@Nullable InputStream	getResourceAsStreamWithChildren(@NotNull String name)	Finds a resource under the given name within this classloader, or if that fails, in any of its children.
@Nullable URL	getResourceAsURLWithChildren(@NotNull String name)	Finds a resource under the given name within this classloader, or if that fails, in any of its children.
void	removeChildInHierarchy(MinestomExtensionClassLoader child)

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, findClass, findLoadedClass, findResource, findSystemClass, getClassLoadingLock, getDefinedPackage, getDefinedPackages, getPackage, getPackages, getParent, getPlatformClassLoader, getResource, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, getUnnamedModule, isRegisteredAsParallelCapable, loadClass, loadClass, registerAsParallelCapable, resolveClass, resources, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

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

Field Details

children

protected final List<MinestomExtensionClassLoader> children

parents

protected final List<HierarchyClassLoader> parents

Constructor Details

HierarchyClassLoader

public HierarchyClassLoader(String name,
 URL[] urls,
 ClassLoader parent)

Method Details

addChild

public void addChild(@NotNull
 @NotNull MinestomExtensionClassLoader loader)

findLibrary

public String findLibrary(String libname)

Overrides:

findLibrary in class ClassLoader

getResourceAsStreamWithChildren

@Nullable
public @Nullable InputStream getResourceAsStreamWithChildren(@NotNull
 @NotNull String name)

Finds a resource under the given name within this classloader, or if that fails, in any of its children. If the resource is found, the resource is opened as an InputStream, otherwise null is returned.

This method distinguishes itself from URLClassLoader.getResourceAsStream(String), which will first query the parent classloader and only then this classloader. Further, URLClassLoader.getResourceAsStream(String) does not query children classloaders.

When failing to open a resource using URL.openStream(), the resource is deemed to no exist in this classloader and will search in children classloaders.

The InputStream returned by this method must be closed manually, it is unspecified whether the returned object will be closed whenever this classloader is closed. A warning will be logged in that circumstance.

Parameters:

name - The pathname of the resource. See URLClassLoader.findResource(String).

Returns:

The InputStream of the corresponding found resource, or null if such a resource does not exist.

Since:

0.0.1

Implementation Note:

Search occurs depth-first, which means that registration order can matter quite a lot.

getResourceAsURLWithChildren

@Nullable
@AvailableSince("4.0.0-a20241006")
public @Nullable URL getResourceAsURLWithChildren(@NotNull
 @NotNull String name)

Finds a resource under the given name within this classloader, or if that fails, in any of its children. If the resource is found, the resource is returned as an URL, otherwise null is returned.

This method distinguishes itself from ClassLoader.getResource(String), which will first query the parent classloader and only then this classloader. Further, ClassLoader.getResource(String) does not query children classloaders.

Parameters:

name - The pathname of the resource.

Returns:

The URL of the corresponding found resource, or null if such a resource does not exist.

Since:

4.0.0-a20241006

Implementation Note:

Search occurs depth-first, which means that registration order can matter quite a lot.

removeChildInHierarchy

public void removeChildInHierarchy(MinestomExtensionClassLoader child)

getName

public String getName()

Overrides:

getName in class ClassLoader