BaseDexClassLoader
public
class
BaseDexClassLoader
extends ClassLoader
java.lang.Object | ||
↳ | java.lang.ClassLoader | |
↳ | dalvik.system.BaseDexClassLoader |
Base class for common functionality between various dex-based
ClassLoader
implementations.
Summary
Public constructors | |
---|---|
BaseDexClassLoader(String dexPath, File optimizedDirectory, String librarySearchPath, ClassLoader parent)
Constructs an instance. |
Public methods | |
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String
|
findLibrary(String name)
Returns the absolute path name of a native library. |
String
|
toString()
Returns a string representation of the object. |
Protected methods | |
---|---|
Class<?>
|
findClass(String name)
Finds the class with the specified binary name. |
URL
|
findResource(String name)
Finds the resource with the given name. |
Enumeration<URL>
|
findResources(String name)
Returns an enumeration of |
Package
|
getPackage(String name)
This method is deprecated.
See |
Inherited methods | |
---|---|
Public constructors
BaseDexClassLoader
public BaseDexClassLoader (String dexPath, File optimizedDirectory, String librarySearchPath, ClassLoader parent)
Constructs an instance.
Note that all the *.jar and *.apk files from dexPath
might be
first extracted in-memory before the code is loaded. This can be avoided
by passing raw dex files (*.dex) in the dexPath
.
Parameters | |
---|---|
dexPath |
String : the list of jar/apk files containing classes and
resources, delimited by File.pathSeparator , which
defaults to ":" on Android. |
optimizedDirectory |
File : this parameter is deprecated and has no effect since API level 26. |
librarySearchPath |
String : the list of directories containing native
libraries, delimited by File.pathSeparator ; may be
null |
parent |
ClassLoader : the parent class loader |
Public methods
findLibrary
public String findLibrary (String name)
Returns the absolute path name of a native library. The VM invokes this
method to locate the native libraries that belong to classes loaded with
this class loader. If this method returns null
, the VM
searches the library along the path specified as the
"java.library.path
" property.
Parameters | |
---|---|
name |
String : The library name |
Returns | |
---|---|
String |
The absolute path of the native library |
toString
public String toString ()
Returns a string representation of the object.
Returns | |
---|---|
String |
a string representation of the object. |
Protected methods
findClass
protected Class<?> findClass (String name)
Finds the class with the specified binary name.
This method should be overridden by class loader implementations that
follow the delegation model for loading classes, and will be invoked by
the loadClass
method after checking the
parent class loader for the requested class.
Parameters | |
---|---|
name |
String : The binary name of the class |
Returns | |
---|---|
Class<?> |
The resulting Class object |
Throws | |
---|---|
ClassNotFoundException |
findResource
protected URL findResource (String name)
Finds the resource with the given name. Class loader implementations should override this method.
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. |
findResources
protected Enumeration<URL> findResources (String name)
Returns an enumeration of URL
objects
representing all the resources with the given name. Class loader
implementations should override this method.
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. |
getPackage
protected Package getPackage (String name)
This method is deprecated.
See ClassLoader#getPackage(String)
Returns package information for the given package.
Unfortunately, instances of this class don't really have this
information, and as a non-secure ClassLoader
, it isn't
even required to, according to the spec. Yet, we want to
provide it, in order to make all those hopeful callers of
myClass.getPackage().getName()
happy. Thus we construct
a Package
object the first time it is being requested
and fill most of the fields with fake values. The Package
object is then put into the ClassLoader
's
package cache, so we see the same one next time. We don't
create Package
objects for null
arguments or
for the default package.
There is a limited chance that we end up with multiple
Package
objects representing the same package: It can
happen when when a package is scattered across different JAR
files which were loaded by different ClassLoader
instances. This is rather unlikely, and given that this whole
thing is more or less a workaround, probably not worth the
effort to address.
Parameters | |
---|---|
name |
String : the name of the class |
Returns | |
---|---|
Package |
the package information for the class, or null
if there is no package information available for it |