OpenJDK 27 · java.rmi.server.RMIClassLoader · APIdia, the JavaDoc alternative

Modifier and Type	Field and Description
private static final RMIClassLoaderSpi	defaultProvider "default" provider instance
private static final RMIClassLoaderSpi	provider provider instance

Access	Constructor and Description
private	RMIClassLoader()

Method Summary

Modifier and Type	Method and Description
public static String	Returns: a string to be used to annotate the given class when it gets marshalled, or `null` getClassAnnotation(Class<?> the class to obtain the annotation for cl) Returns the annotation string (representing a location for the class definition) that RMI will use to annotate the class descriptor when marshalling objects of the given class.
public static ClassLoader	Returns: a class loader that loads classes from the given codebase URL path getClassLoader(String the list of URLs (space-separated) from which the returned class loader will load classes from, or `null` codebase) Returns a class loader that loads classes from the given codebase URL path.
public static RMIClassLoaderSpi	Returns: the canonical instance of the default service provider getDefaultProviderInstance() Returns the canonical instance of the default provider for the service provider interface `RMIClassLoaderSpi`.
public static Object	Returns: null getSecurityContext(ClassLoader a class loader from which to get the security context loader) Deprecated no replacement. This method has no purpose in the absence of a Security Manager. Always returns null.
private static RMIClassLoaderSpi	initializeProvider() Chooses provider instance, following above documentation.
public static Class<?>	Returns: the `Class` object representing the loaded class loadClass(String the name of the class to load name) Deprecated replaced by `loadClass(String,String)` method Loads the class with the specified `name`.
public static Class<?>	Returns: the `Class` object representing the loaded class loadClass(URL the URL to load the class from, or `null` codebase, String the name of the class to load name) Loads a class from a codebase URL.
public static Class<?>	Returns: the `Class` object representing the loaded class loadClass(String the list of URLs (separated by spaces) to load the class from, or `null` codebase, String the name of the class to load name) Loads a class from a codebase URL path.
public static Class<?>	Returns: the `Class` object representing the loaded class loadClass(String the list of URLs (separated by spaces) to load the class from, or `null` codebase, String the name of the class to load name, ClassLoader additional contextual class loader to use, or `null` defaultLoader) Loads a class from a codebase URL path, optionally using the supplied loader.
public static Class<?>	Returns: a dynamic proxy class that implements the named interfaces loadProxyClass(String the list of URLs (space-separated) to load classes from, or `null` codebase, String[] the names of the interfaces for the proxy class to implement interfaces, ClassLoader additional contextual class loader to use, or `null` defaultLoader) Loads a dynamic proxy class (see `java.lang.reflect.Proxy`) that implements a set of interfaces with the given names from a codebase URL path.
private static RMIClassLoaderSpi	newDefaultProviderInstance() Creates an instance of the default provider class.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

defaultProvider	back to summary
private static final RMIClassLoaderSpi defaultProvider "default" provider instance

provider	back to summary
private static final RMIClassLoaderSpi provider provider instance

RMIClassLoader	back to summary
private RMIClassLoader()

Method Detail

getClassAnnotation back to summary

getClassAnnotation	back to summary
public static String getClassAnnotation(Class<?> cl) Returns the annotation string (representing a location for the class definition) that RMI will use to annotate the class descriptor when marshalling objects of the given class. This method delegates to the `RMIClassLoaderSpi#getClassAnnotation(Class)` method of the provider instance, passing `cl` as the argument. Parameters cl:Class<?> the class to obtain the annotation for Returns:String a string to be used to annotate the given class when it gets marshalled, or `null` Exceptions NullPointerException: if `cl` is `null` Since 1.2

public static String getClassAnnotation(Class<?> cl)

Returns the annotation string (representing a location for the class definition) that RMI will use to annotate the class descriptor when marshalling objects of the given class.

This method delegates to the RMIClassLoaderSpi#getClassAnnotation(Class) method of the provider instance, passing cl as the argument.

Parameters

cl:Class<?>: the class to obtain the annotation for

Returns:String

a string to be used to annotate the given class when it gets marshalled, or null

Exceptions

NullPointerException:: if cl is null

Since

1.2

getClassLoader back to summary

getClassLoader	back to summary
public static ClassLoader getClassLoader(String codebase) throws MalformedURLException Returns a class loader that loads classes from the given codebase URL path. The class loader returned is the class loader that the `loadClass(String, String)` method would use to load classes for the same `codebase` argument. This method delegates to the `RMIClassLoaderSpi#getClassLoader(String)` method of the provider instance, passing `codebase` as the argument. Parameters codebase:String the list of URLs (space-separated) from which the returned class loader will load classes from, or `null` Returns:ClassLoader a class loader that loads classes from the given codebase URL path Exceptions MalformedURLException: if `codebase` is non-`null` and contains an invalid URL, or if `codebase` is `null` and a provider-specific URL used to identify the class loader is invalid Since 1.3

public static ClassLoader getClassLoader(String codebase) throws MalformedURLException

Returns a class loader that loads classes from the given codebase URL path.

The class loader returned is the class loader that the loadClass(String, String) method would use to load classes for the same codebase argument.

This method delegates to the RMIClassLoaderSpi#getClassLoader(String) method of the provider instance, passing codebase as the argument.

Parameters

codebase:String: the list of URLs (space-separated) from which the returned class loader will load classes from, or null

Returns:ClassLoader

a class loader that loads classes from the given codebase URL path

Exceptions

MalformedURLException:: if codebase is non-null and contains an invalid URL, or if codebase is null and a provider-specific URL used to identify the class loader is invalid

Since

1.3

getDefaultProviderInstance back to summary

getDefaultProviderInstance	back to summary
public static RMIClassLoaderSpi getDefaultProviderInstance() Returns the canonical instance of the default provider for the service provider interface `RMIClassLoaderSpi`. If the system property `java.rmi.server.RMIClassLoaderSpi` is not defined, then the `RMIClassLoader` static methods `loadClass(URL, String)` `loadClass(String, String)` `loadClass(String, String, ClassLoader)` `loadProxyClass(String, String[], ClassLoader)` `getClassLoader(String)` `getClassAnnotation(Class)` will use the canonical instance of the default provider as the service provider instance. The default service provider instance implements `RMIClassLoaderSpi` as follows: The `getClassAnnotation` method returns a `String` representing the codebase URL path that a remote party should use to download the definition for the specified class. The format of the returned string is a path of URLs separated by spaces. The codebase string returned depends on the defining class loader of the specified class: If the class loader is the system class loader (see `ClassLoader#getSystemClassLoader`), a parent of the system class loader such as the loader used for installed extensions, or the bootstrap class loader (which may be represented by `null`), then the value of the `java.rmi.server.codebase` property (or possibly an earlier cached value) is returned, or `null` is returned if that property is not set. Otherwise, if the class loader is an instance of `URLClassLoader`, then the returned string is a space-separated list of the external forms of the URLs returned by invoking the `getURLs` methods of the loader. Finally, if the class loader is not an instance of `URLClassLoader`, then the value of the `java.rmi.server.codebase` property (or possibly an earlier cached value) is returned, or `null` is returned if that property is not set. For the implementations of the methods described below, which all take a `String` parameter named `codebase` that is a space-separated list of URLs, the `codebase` argument is ignored. Class loading proceeds using the the current thread's context class loader (see `Thread#getContextClassLoader()`), which is also considered to be the codebase loader, irrespective of any value passed as the `codebase` argument. The `getClassLoader` method returns the current thread's context class loader. The `loadClass` method attempts to load the class with the specified name as follows: If the `defaultLoader` argument is non-`null`, it first attempts to load the class with the specified `name` using the `defaultLoader`, as if by evaluating Class.forName(name, false, defaultLoader) If the class is successfully loaded from the `defaultLoader`, that class is returned. If an exception other than `ClassNotFoundException` is thrown, that exception is thrown to the caller. Next, the `loadClass` method attempts to load the class with the specified `name` using the current thread's context class loader. The `loadProxyClass` method attempts to return a dynamic proxy class with the named interface as follows: If the `defaultLoader` argument is non-`null` and all of the named interfaces can be resolved through that loader, then, if all of the resolved interfaces are `public`, then it first attempts to obtain a dynamic proxy class (using `Proxy.getProxyClass`) for the resolved interfaces defined in the codebase loader; if that attempt throws an `IllegalArgumentException`, it then attempts to obtain a dynamic proxy class for the resolved interfaces defined in the `defaultLoader`. If both attempts throw `IllegalArgumentException`, then this method throws a `ClassNotFoundException`. If any other exception is thrown, that exception is thrown to the caller. if all of the non-`public` resolved interfaces are defined in the same class loader, then it attempts to obtain a dynamic proxy class for the resolved interfaces defined in that loader. otherwise, a `LinkageError` is thrown (because a class that implements all of the specified interfaces cannot be defined in any loader). Otherwise, if all of the named interfaces can be resolved through the codebase loader, then, if all of the resolved interfaces are `public`, then it attempts to obtain a dynamic proxy class for the resolved interfaces in the codebase loader. If the attempt throws an `IllegalArgumentException`, then this method throws a `ClassNotFoundException`. if all of the non-`public` resolved interfaces are defined in the same class loader, then it attempts to obtain a dynamic proxy class for the resolved interfaces defined in that loader. otherwise, a `LinkageError` is thrown (because a class that implements all of the specified interfaces cannot be defined in any loader). Otherwise, a `ClassNotFoundException` is thrown for one of the named interfaces that could not be resolved. Returns:RMIClassLoaderSpi the canonical instance of the default service provider Since 1.4

public static RMIClassLoaderSpi getDefaultProviderInstance()

Returns the canonical instance of the default provider for the service provider interface RMIClassLoaderSpi. If the system property java.rmi.server.RMIClassLoaderSpi is not defined, then the RMIClassLoader static methods

will use the canonical instance of the default provider as the service provider instance.

The default service provider instance implements RMIClassLoaderSpi as follows:

The getClassAnnotation method returns a String representing the codebase URL path that a remote party should use to download the definition for the specified class. The format of the returned string is a path of URLs separated by spaces. The codebase string returned depends on the defining class loader of the specified class:

If the class loader is the system class loader (see ClassLoader#getSystemClassLoader), a parent of the system class loader such as the loader used for installed extensions, or the bootstrap class loader (which may be represented by null), then the value of the java.rmi.server.codebase property (or possibly an earlier cached value) is returned, or null is returned if that property is not set.
Otherwise, if the class loader is an instance of URLClassLoader, then the returned string is a space-separated list of the external forms of the URLs returned by invoking the getURLs methods of the loader.
Finally, if the class loader is not an instance of URLClassLoader, then the value of the java.rmi.server.codebase property (or possibly an earlier cached value) is returned, or null is returned if that property is not set.

For the implementations of the methods described below, which all take a String parameter named codebase that is a space-separated list of URLs, the codebase argument is ignored. Class loading proceeds using the the current thread's context class loader (see Thread#getContextClassLoader()), which is also considered to be the codebase loader, irrespective of any value passed as the codebase argument.
The getClassLoader method returns the current thread's context class loader.
The loadClass method attempts to load the class with the specified name as follows:
If the defaultLoader argument is non-null, it first attempts to load the class with the specified name using the defaultLoader, as if by evaluating
    Class.forName(name, false, defaultLoader)
If the class is successfully loaded from the defaultLoader, that class is returned. If an exception other than ClassNotFoundException is thrown, that exception is thrown to the caller.
Next, the loadClass method attempts to load the class with the specified name using the current thread's context class loader.
The loadProxyClass method attempts to return a dynamic proxy class with the named interface as follows:

If the defaultLoader argument is non-null and all of the named interfaces can be resolved through that loader, then,

if all of the resolved interfaces are public, then it first attempts to obtain a dynamic proxy class (using Proxy.getProxyClass) for the resolved interfaces defined in the codebase loader; if that attempt throws an IllegalArgumentException, it then attempts to obtain a dynamic proxy class for the resolved interfaces defined in the defaultLoader. If both attempts throw IllegalArgumentException, then this method throws a ClassNotFoundException. If any other exception is thrown, that exception is thrown to the caller.
if all of the non-public resolved interfaces are defined in the same class loader, then it attempts to obtain a dynamic proxy class for the resolved interfaces defined in that loader.
otherwise, a LinkageError is thrown (because a class that implements all of the specified interfaces cannot be defined in any loader).

Otherwise, if all of the named interfaces can be resolved through the codebase loader, then,

if all of the resolved interfaces are public, then it attempts to obtain a dynamic proxy class for the resolved interfaces in the codebase loader. If the attempt throws an IllegalArgumentException, then this method throws a ClassNotFoundException.
if all of the non-public resolved interfaces are defined in the same class loader, then it attempts to obtain a dynamic proxy class for the resolved interfaces defined in that loader.
otherwise, a LinkageError is thrown (because a class that implements all of the specified interfaces cannot be defined in any loader).

Otherwise, a ClassNotFoundException is thrown for one of the named interfaces that could not be resolved.

Returns:RMIClassLoaderSpi: the canonical instance of the default service provider
Since: 1.4

getSecurityContext	back to summary
public static Object getSecurityContext(ClassLoader loader) Deprecated no replacement. This method has no purpose in the absence of a Security Manager. Always returns null. Parameters loader:ClassLoader a class loader from which to get the security context Returns:Object null Annotations @Deprecated

getSecurityContext

back to summary

public static Object getSecurityContext(ClassLoader loader)

Deprecated

no replacement. This method has no purpose in the absence of a Security Manager.

Always returns null.

Parameters

loader:ClassLoader: a class loader from which to get the security context

Returns:Object

null

Annotations

@Deprecated

initializeProvider	back to summary
private static RMIClassLoaderSpi initializeProvider() Chooses provider instance, following above documentation. This method assumes that it has been invoked in a privileged block.

loadClass back to summary

loadClass	back to summary
public static Class<?> loadClass(String name) throws MalformedURLException, ClassNotFoundException Deprecated replaced by `loadClass(String,String)` method Loads the class with the specified `name`. This method delegates to `loadClass(String, String)`, passing `null` as the first argument and `name` as the second argument. Parameters name:String the name of the class to load Returns:Class<?> the `Class` object representing the loaded class Annotations @Deprecated Exceptions MalformedURLException: if a provider-specific URL used to load classes is invalid ClassNotFoundException: if a definition for the class could not be found at the codebase location See Also `loadClass(String, String)`

public static Class<?> loadClass(String name) throws MalformedURLException, ClassNotFoundException

Deprecated

replaced by loadClass(String,String) method

Loads the class with the specified name.

This method delegates to loadClass(String, String), passing null as the first argument and name as the second argument.

Parameters

name:String: the name of the class to load

Returns:Class<?>

the Class object representing the loaded class

Annotations

@Deprecated

Exceptions

MalformedURLException:: if a provider-specific URL used to load classes is invalid
ClassNotFoundException:: if a definition for the class could not be found at the codebase location

See Also

loadClass(String, String)

loadClass back to summary

loadClass	back to summary
public static Class<?> loadClass(URL codebase, String name) throws MalformedURLException, ClassNotFoundException Loads a class from a codebase URL. If `codebase` is `null`, then this method will behave the same as `loadClass(String, String)` with a `null` `codebase` and the given class name. This method delegates to the `RMIClassLoaderSpi#loadClass(String, String, ClassLoader)` method of the provider instance, passing the result of invoking `URL#toString` on the given URL (or `null` if `codebase` is null) as the first argument, `name` as the second argument, and `null` as the third argument. Parameters codebase:URL the URL to load the class from, or `null` name:String the name of the class to load Returns:Class<?> the `Class` object representing the loaded class Exceptions MalformedURLException: if `codebase` is `null` and a provider-specific URL used to load classes is invalid ClassNotFoundException: if a definition for the class could not be found at the specified URL

public static Class<?> loadClass(URL codebase, String name) throws MalformedURLException, ClassNotFoundException

Loads a class from a codebase URL. If codebase is null, then this method will behave the same as loadClass(String, String) with a null codebase and the given class name.

This method delegates to the RMIClassLoaderSpi#loadClass(String, String, ClassLoader) method of the provider instance, passing the result of invoking URL#toString on the given URL (or null if codebase is null) as the first argument, name as the second argument, and null as the third argument.

Parameters

codebase:URL: the URL to load the class from, or null
name:String: the name of the class to load

Returns:Class<?>

the Class object representing the loaded class

Exceptions

MalformedURLException:: if codebase is null and a provider-specific URL used to load classes is invalid
ClassNotFoundException:: if a definition for the class could not be found at the specified URL

loadClass back to summary

loadClass	back to summary
public static Class<?> loadClass(String codebase, String name) throws MalformedURLException, ClassNotFoundException Loads a class from a codebase URL path. This method delegates to the `RMIClassLoaderSpi#loadClass(String, String, ClassLoader)` method of the provider instance, passing `codebase` as the first argument, `name` as the second argument, and `null` as the third argument. Parameters codebase:String the list of URLs (separated by spaces) to load the class from, or `null` name:String the name of the class to load Returns:Class<?> the `Class` object representing the loaded class Exceptions MalformedURLException: if `codebase` is non-`null` and contains an invalid URL, or if `codebase` is `null` and a provider-specific URL used to load classes is invalid ClassNotFoundException: if a definition for the class could not be found at the specified location Since 1.2

public static Class<?> loadClass(String codebase, String name) throws MalformedURLException, ClassNotFoundException

Loads a class from a codebase URL path.

This method delegates to the RMIClassLoaderSpi#loadClass(String, String, ClassLoader) method of the provider instance, passing codebase as the first argument, name as the second argument, and null as the third argument.

Parameters

codebase:String: the list of URLs (separated by spaces) to load the class from, or null
name:String: the name of the class to load

Returns:Class<?>

the Class object representing the loaded class

Exceptions

MalformedURLException:: if codebase is non-null and contains an invalid URL, or if codebase is null and a provider-specific URL used to load classes is invalid
ClassNotFoundException:: if a definition for the class could not be found at the specified location

Since

1.2

loadClass back to summary

loadClass	back to summary
public static Class<?> loadClass(String codebase, String name, ClassLoader defaultLoader) throws MalformedURLException, ClassNotFoundException Loads a class from a codebase URL path, optionally using the supplied loader. This method should be used when the caller would like to make available to the provider implementation an additional contextual class loader to consider, such as the loader of a caller on the stack. Typically, a provider implementation will attempt to resolve the named class using the given `defaultLoader`, if specified, before attempting to resolve the class from the codebase URL path. This method delegates to the `RMIClassLoaderSpi#loadClass(String, String, ClassLoader)` method of the provider instance, passing `codebase` as the first argument, `name` as the second argument, and `defaultLoader` as the third argument. Parameters codebase:String the list of URLs (separated by spaces) to load the class from, or `null` name:String the name of the class to load defaultLoader:ClassLoader additional contextual class loader to use, or `null` Returns:Class<?> the `Class` object representing the loaded class Exceptions MalformedURLException: if `codebase` is non-`null` and contains an invalid URL, or if `codebase` is `null` and a provider-specific URL used to load classes is invalid ClassNotFoundException: if a definition for the class could not be found at the specified location Since 1.4

public static Class<?> loadClass(String codebase, String name, ClassLoader defaultLoader) throws MalformedURLException, ClassNotFoundException

Loads a class from a codebase URL path, optionally using the supplied loader. This method should be used when the caller would like to make available to the provider implementation an additional contextual class loader to consider, such as the loader of a caller on the stack. Typically, a provider implementation will attempt to resolve the named class using the given defaultLoader, if specified, before attempting to resolve the class from the codebase URL path.

Parameters

codebase:String: the list of URLs (separated by spaces) to load the class from, or null
name:String: the name of the class to load
defaultLoader:ClassLoader: additional contextual class loader to use, or null

Returns:Class<?>

the Class object representing the loaded class

Exceptions

MalformedURLException:: if codebase is non-null and contains an invalid URL, or if codebase is null and a provider-specific URL used to load classes is invalid
ClassNotFoundException:: if a definition for the class could not be found at the specified location

Since

1.4

loadProxyClass back to summary

loadProxyClass	back to summary
public static Class<?> loadProxyClass(String codebase, String[] interfaces, ClassLoader defaultLoader) throws ClassNotFoundException, MalformedURLException Loads a dynamic proxy class (see `java.lang.reflect.Proxy`) that implements a set of interfaces with the given names from a codebase URL path. The interfaces will be resolved similar to classes loaded via the `loadClass(String, String)` method using the given `codebase`. This method delegates to the `RMIClassLoaderSpi#loadProxyClass(String, String[], ClassLoader)` method of the provider instance, passing `codebase` as the first argument, `interfaces` as the second argument, and `defaultLoader` as the third argument. Parameters codebase:String the list of URLs (space-separated) to load classes from, or `null` interfaces:String[] the names of the interfaces for the proxy class to implement defaultLoader:ClassLoader additional contextual class loader to use, or `null` Returns:Class<?> a dynamic proxy class that implements the named interfaces Exceptions ClassNotFoundException: if a definition for one of the named interfaces could not be found at the specified location, or if creation of the dynamic proxy class failed (such as if `java.lang.reflect.Proxy#getProxyClass(ClassLoader, Class[])` would throw an `IllegalArgumentException` for the given interface list) MalformedURLException: if `codebase` is non-`null` and contains an invalid URL, or if `codebase` is `null` and a provider-specific URL used to load classes is invalid Since 1.4

public static Class<?> loadProxyClass(String codebase, String[] interfaces, ClassLoader defaultLoader) throws ClassNotFoundException, MalformedURLException

Loads a dynamic proxy class (see java.lang.reflect.Proxy) that implements a set of interfaces with the given names from a codebase URL path.

The interfaces will be resolved similar to classes loaded via the loadClass(String, String) method using the given codebase.

This method delegates to the RMIClassLoaderSpi#loadProxyClass(String, String[], ClassLoader) method of the provider instance, passing codebase as the first argument, interfaces as the second argument, and defaultLoader as the third argument.

Parameters

codebase:String: the list of URLs (space-separated) to load classes from, or null
interfaces:String[]: the names of the interfaces for the proxy class to implement
defaultLoader:ClassLoader: additional contextual class loader to use, or null

Returns:Class<?>

a dynamic proxy class that implements the named interfaces

Exceptions

ClassNotFoundException:: if a definition for one of the named interfaces could not be found at the specified location, or if creation of the dynamic proxy class failed (such as if java.lang.reflect.Proxy#getProxyClass(ClassLoader, Class[]) would throw an IllegalArgumentException for the given interface list)
MalformedURLException:: if codebase is non-null and contains an invalid URL, or if codebase is null and a provider-specific URL used to load classes is invalid

Since

1.4

newDefaultProviderInstance	back to summary
private static RMIClassLoaderSpi newDefaultProviderInstance() Creates an instance of the default provider class.

public Class RMIClassLoader

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail