DelegateLastClassLoader
public
final
class
DelegateLastClassLoader
extends PathClassLoader
java.lang.Object | ||||
↳ | java.lang.ClassLoader | |||
↳ | dalvik.system.BaseDexClassLoader | |||
↳ | dalvik.system.PathClassLoader | |||
↳ | dalvik.system.DelegateLastClassLoader |
A ClassLoader
implementation that implements a delegate last lookup policy.
For every class or resource this loader is requested to load, the following lookup order
is employed:
- The boot classpath is always searched first
- Then, the list of
dex
files associated with this classloaders'sdexPath
is searched. - Finally, this classloader will delegate to the specified
parent
.
Summary
Public constructors | |
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DelegateLastClassLoader(String dexPath, ClassLoader parent)
Equivalent to calling |
|
DelegateLastClassLoader(String dexPath, String librarySearchPath, ClassLoader parent)
Equivalent to calling |
|
DelegateLastClassLoader(String dexPath, String librarySearchPath, ClassLoader parent, boolean delegateResourceLoading)
Creates a |
Public methods | |
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URL
|
getResource(String name)
Finds the resource with the given name. |
Enumeration<URL>
|
getResources(String name)
Finds all the resources with the given name. |
Protected methods | |
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Class<?>
|
loadClass(String name, boolean resolve)
Loads the class with the specified binary name. |
Inherited methods | |
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Public constructors
DelegateLastClassLoader
public DelegateLastClassLoader (String dexPath, ClassLoader parent)
Equivalent to calling DelegateLastClassLoader(java.lang.String, java.lang.String, java.lang.ClassLoader, boolean)
with librarySearchPath = null, delegateResourceLoading = true
.
Parameters | |
---|---|
dexPath |
String |
parent |
ClassLoader |
DelegateLastClassLoader
public DelegateLastClassLoader (String dexPath, String librarySearchPath, ClassLoader parent)
Equivalent to calling DelegateLastClassLoader(java.lang.String, java.lang.String, java.lang.ClassLoader, boolean)
with delegateResourceLoading = true
.
Parameters | |
---|---|
dexPath |
String |
librarySearchPath |
String |
parent |
ClassLoader |
DelegateLastClassLoader
public DelegateLastClassLoader (String dexPath, String librarySearchPath, ClassLoader parent, boolean delegateResourceLoading)
Creates a DelegateLastClassLoader
that operates on a given dexPath
and a librarySearchPath
.
The dexPath
should consist of one or more of the following, separated by
File.pathSeparator
, which is ":"
on Android.
- JAR/ZIP/APK files, possibly containing a "classes.dex" file as well as arbitrary resources.
- Raw ".dex" files (not inside a zip file).
PathClassLoader
, this classloader will attempt to locate classes
(or resources) using the following lookup order.
- The boot classpath is always searched first.
- Then, the list of
dex
files contained indexPath
is searched./li> - Lastly, this classloader will delegate to the specified
parent
.
parent
is always searched first.
librarySearchPath
specifies one more directories containing native library files,
separated by File.pathSeparator
.
Parameters | |
---|---|
dexPath |
String : the list of jar/apk files containing classes and resources, delimited by
File.pathSeparator , which defaults to ":" on Android.
This value cannot be null . |
librarySearchPath |
String : the list of directories containing native libraries, delimited
by File.pathSeparator ; may be null . |
parent |
ClassLoader : the parent class loader. May be null for the boot classloader. |
delegateResourceLoading |
boolean : whether to delegate resource loading to the parent if
the resource is not found. This does not affect class
loading delegation. |
Public methods
getResource
public URL getResource (String name)
Finds the resource with the given name. A resource is some data (images, audio, text, etc) that can be accessed by class code in a way that is independent of the location of the code.
The name of a resource is a '/
'-separated path name thatf
identifies the resource.
Parameters | |
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name |
String : The resource name |
Returns | |
---|---|
URL |
URL object for reading the resource; null if
the resource could not be found, a URL could not be
constructed to locate the resource, the resource is in a package
that is not opened unconditionally, or access to the resource is
denied by the security manager. |
getResources
public Enumeration<URL> getResources (String name)
Finds all the resources with the given name. A resource is some data (images, audio, text, etc) that can be accessed by class code in a way that is independent of the location of the code.
The name of a resource is a /
-separated path name that
identifies the resource.
Parameters | |
---|---|
name |
String : The resource name |
Returns | |
---|---|
Enumeration<URL> |
An enumeration of URL objects for the
resource. If no resources could be found, the enumeration will
be empty. Resources for which a URL cannot be
constructed, are in a package that is not opened
unconditionally, or access to the resource is denied by the
security manager, are not returned in the enumeration. |
Throws | |
---|---|
IOException |
Protected methods
loadClass
protected Class<?> loadClass (String name, boolean resolve)
Loads the class with the specified binary name. The default implementation of this method searches for classes in the following order:
Invoke
findLoadedClass(java.lang.String)
to check if the class has already been loaded.Invoke the
loadClass
method on the parent class loader. If the parent isnull
the class loader built into the virtual machine is used, instead.Invoke the
findClass(java.lang.String)
method to find the class.
If the class was found using the above steps, and the
resolve
flag is true, this method will then invoke the resolveClass(java.lang.Class)
method on the resulting Class
object.
Subclasses of ClassLoader
are encouraged to override findClass(java.lang.String)
, rather than this method.
Parameters | |
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name |
String : The binary name of the class |
resolve |
boolean : If true then resolve the class |
Returns | |
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Class<?> |
The resulting Class object |
Throws | |
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ClassNotFoundException |