public class MultipleParentClassLoader extends InjectionClassLoader
This ClassLoader
is capable of loading classes from multiple parents. This class loader
implicitly defines the bootstrap class loader to be its direct parent as it is required for all class loaders.
This can be useful when creating a type that inherits a super type and interfaces that are defined by different,
non-compatible class loaders.
Note: Instances of this class loader can have the same class loader as its parent multiple times,
either directly or indirectly by multiple parents sharing a common parent class loader. By definition,
this implies that the bootstrap class loader is #(direct parents) + 1
times a parent of this class loader.
For the ClassLoader.getResources(java.lang.String)
method, this means that this class loader
might return the same url multiple times by representing the same class loader multiple times.
Important: This class loader does not support the location of packages from its multiple parents. This breaks package equality when loading classes by either loading them directly via this class loader (e.g. by subclassing) or by loading classes with child class loaders of this class loader.
Modifier and Type | Class and Description |
---|---|
static class |
MultipleParentClassLoader.Builder
A builder to collect class loader and that creates a
MultipleParentClassLoader only if multiple or no
ClassLoader s are found in the process. |
protected static class |
MultipleParentClassLoader.CompoundEnumeration
A compound URL enumeration.
|
InjectionClassLoader.Strategy
Modifier and Type | Field and Description |
---|---|
private java.util.List<? extends java.lang.ClassLoader> |
parents
The parents of this class loader in their application order.
|
Constructor and Description |
---|
MultipleParentClassLoader(java.lang.ClassLoader parent,
java.util.List<? extends java.lang.ClassLoader> parents)
Creates a new class loader with multiple parents.
|
MultipleParentClassLoader(java.lang.ClassLoader parent,
java.util.List<? extends java.lang.ClassLoader> parents,
boolean sealed)
Creates a new class loader with multiple parents.
|
MultipleParentClassLoader(java.util.List<? extends java.lang.ClassLoader> parents)
Creates a new class loader with multiple parents.
|
Modifier and Type | Method and Description |
---|---|
protected java.util.Map<java.lang.String,java.lang.Class<?>> |
doDefineClasses(java.util.Map<java.lang.String,byte[]> typeDefinitions)
Defines a group of types to be loaded by this class loader.
|
java.net.URL |
getResource(java.lang.String name) |
java.util.Enumeration<java.net.URL> |
getResources(java.lang.String name) |
protected java.lang.Class<?> |
loadClass(java.lang.String name,
boolean resolve) |
defineClass, defineClasses, isSealed
clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findClass, findLibrary, findLoadedClass, findResource, findResources, findSystemClass, getClassLoadingLock, getPackage, getPackages, getParent, getResourceAsStream, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, loadClass, registerAsParallelCapable, resolveClass, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners
private final java.util.List<? extends java.lang.ClassLoader> parents
public MultipleParentClassLoader(java.util.List<? extends java.lang.ClassLoader> parents)
parents
- The parents of this class loader in their application order. This list must not contain null
,
i.e. the bootstrap class loader which is an implicit parent of any class loader.public MultipleParentClassLoader(java.lang.ClassLoader parent, java.util.List<? extends java.lang.ClassLoader> parents)
parent
- An explicit parent in compliance with the class loader API. This explicit parent should only be set if
the current platform does not allow creating a class loader that extends the bootstrap loader.parents
- The parents of this class loader in their application order. This list must not contain null
,
i.e. the bootstrap class loader which is an implicit parent of any class loader.public MultipleParentClassLoader(java.lang.ClassLoader parent, java.util.List<? extends java.lang.ClassLoader> parents, boolean sealed)
parent
- An explicit parent in compliance with the class loader API. This explicit parent should only be set if
the current platform does not allow creating a class loader that extends the bootstrap loader.parents
- The parents of this class loader in their application order. This list must not contain null
,
i.e. the bootstrap class loader which is an implicit parent of any class loader.sealed
- true
if the class loader is sealed for injection of additional classes.protected java.lang.Class<?> loadClass(java.lang.String name, boolean resolve) throws java.lang.ClassNotFoundException
loadClass
in class java.lang.ClassLoader
java.lang.ClassNotFoundException
public java.net.URL getResource(java.lang.String name)
getResource
in class java.lang.ClassLoader
public java.util.Enumeration<java.net.URL> getResources(java.lang.String name) throws java.io.IOException
getResources
in class java.lang.ClassLoader
java.io.IOException
protected java.util.Map<java.lang.String,java.lang.Class<?>> doDefineClasses(java.util.Map<java.lang.String,byte[]> typeDefinitions)
InjectionClassLoader
doDefineClasses
in class InjectionClassLoader
typeDefinitions
- The types binary representations.