java.lang.Object
- java.lang.ClassLoader
- - org.springframework.core.DecoratingClassLoader
  - - org.springframework.core.OverridingClassLoader

Direct Known Subclasses:
SimpleInstrumentableClassLoader, SimpleThrowawayClassLoader
```
public class OverridingClassLoader
extends DecoratingClassLoader
```
ClassLoader that does not always delegate to the parent loader as normal class loaders do. This enables, for example, instrumentation to be forced in the overriding ClassLoader, or a "throwaway" class loading behavior where selected application classes are temporarily loaded in the overriding ClassLoader for introspection purposes before eventually loading an instrumented version of the class in the given parent ClassLoader.
Since:
2.0.1
Author:
Rod Johnson, Juergen Hoeller

Field Summary
Fields
Modifier and Type Field Description
static String[] DEFAULT_EXCLUDED_PACKAGES
Packages that are excluded by default.

Constructor Summary

Constructors
Constructor	Description
`OverridingClassLoader(ClassLoader parent)`	Create a new OverridingClassLoader for the given ClassLoader.
`OverridingClassLoader(ClassLoader parent, ClassLoader overrideDelegate)`	Create a new OverridingClassLoader for the given ClassLoader.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected boolean`	`isEligibleForOverriding(String className)`	Determine whether the specified class is eligible for overriding by this class loader.
`protected byte[]`	`loadBytesForClass(String name)`	Load the defining bytes for the given class, to be turned into a Class object through a `ClassLoader.defineClass(byte[], int, int)` call.
`Class<?>`	`loadClass(String name)`
`protected Class<?>`	`loadClass(String name, boolean resolve)`
`protected Class<?>`	`loadClassForOverriding(String name)`	Load the specified class for overriding purposes in this ClassLoader.
`protected InputStream`	`openStreamForClass(String name)`	Open an InputStream for the specified class.
`protected byte[]`	`transformIfNecessary(String name, byte[] bytes)`	Transformation hook to be implemented by subclasses.

Methods inherited from class org.springframework.core.DecoratingClassLoader
excludeClass, excludePackage, isExcluded

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DEFAULT_EXCLUDED_PACKAGES
```
public static final String[] DEFAULT_EXCLUDED_PACKAGES
```
    Packages that are excluded by default.
- Constructor Detail
  - OverridingClassLoader
```
public OverridingClassLoader(@Nullable
                             ClassLoader parent)
```
    Create a new OverridingClassLoader for the given ClassLoader.
    Parameters:
    parent - the ClassLoader to build an overriding ClassLoader for
  - OverridingClassLoader
```
public OverridingClassLoader(@Nullable
                             ClassLoader parent,
                             @Nullable
                             ClassLoader overrideDelegate)
```
    Create a new OverridingClassLoader for the given ClassLoader.
    Parameters:
    parent - the ClassLoader to build an overriding ClassLoader for
    overrideDelegate - the ClassLoader to delegate to for overriding
    Since:
    4.3
- Method Detail
  - loadClass
```
public Class<?> loadClass(String name)
                   throws ClassNotFoundException
```
    Overrides:
    loadClass in class ClassLoader
    Throws:
    ClassNotFoundException
  - loadClass
```
protected Class<?> loadClass(String name,
                             boolean resolve)
                      throws ClassNotFoundException
```
    Overrides:
    loadClass in class ClassLoader
    Throws:
    ClassNotFoundException
  - isEligibleForOverriding
```
protected boolean isEligibleForOverriding(String className)
```
    Determine whether the specified class is eligible for overriding by this class loader.
    Parameters:
    className - the class name to check
    Returns:
    whether the specified class is eligible
    See Also:
    DecoratingClassLoader.isExcluded(java.lang.String)
  - loadClassForOverriding
```
@Nullable
protected Class<?> loadClassForOverriding(String name)
                                   throws ClassNotFoundException
```
    Load the specified class for overriding purposes in this ClassLoader.
    The default implementation delegates to ClassLoader.findLoadedClass(java.lang.String), loadBytesForClass(java.lang.String) and ClassLoader.defineClass(byte[], int, int).
    Parameters:
    name - the name of the class
    Returns:
    the Class object, or null if no class defined for that name
    Throws:
    ClassNotFoundException - if the class for the given name couldn't be loaded
  - loadBytesForClass
```
@Nullable
protected byte[] loadBytesForClass(String name)
                            throws ClassNotFoundException
```
    Load the defining bytes for the given class, to be turned into a Class object through a ClassLoader.defineClass(byte[], int, int) call.
    The default implementation delegates to openStreamForClass(java.lang.String) and transformIfNecessary(java.lang.String, byte[]).
    Parameters:
    name - the name of the class
    Returns:
    the byte content (with transformers already applied), or null if no class defined for that name
    Throws:
    ClassNotFoundException - if the class for the given name couldn't be loaded
  - openStreamForClass
```
@Nullable
protected InputStream openStreamForClass(String name)
```
    Open an InputStream for the specified class.
    The default implementation loads a standard class file through the parent ClassLoader's getResourceAsStream method.
    Parameters:
    name - the name of the class
    Returns:
    the InputStream containing the byte code for the specified class
  - transformIfNecessary
```
protected byte[] transformIfNecessary(String name,
                                      byte[] bytes)
```
    Transformation hook to be implemented by subclasses.
    The default implementation simply returns the given bytes as-is.
    Parameters:
    name - the fully-qualified name of the class being transformed
    bytes - the raw bytes of the class
    Returns:
    the transformed bytes (never null; same as the input bytes if the transformation produced no changes)

Class OverridingClassLoader

Field Summary

Constructor Summary

Method Summary

Methods inherited from class org.springframework.core.DecoratingClassLoader

Methods inherited from class java.lang.ClassLoader

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_EXCLUDED_PACKAGES

Constructor Detail

OverridingClassLoader

OverridingClassLoader

Method Detail

loadClass

loadClass

isEligibleForOverriding

loadClassForOverriding

loadBytesForClass

openStreamForClass

transformIfNecessary