Factory to create JMX API connector clients. There are no instances of this class.

Connections are usually made using the connect method of this class. More advanced applications can separate the creation of the connector client, using newJMXConnector and the establishment of the connection itself, using JMXConnector.connect(Map).

Each client is created by an instance of JMXConnectorProvider. This instance is found as follows. Suppose the given JMXServiceURL looks like "service:jmx:protocol:remainder". Then the factory will attempt to find the appropriate JMXConnectorProvider for protocol. Each occurrence of the character + or - in protocol is replaced by . or _, respectively.

A provider package list is searched for as follows:

1. If the environment parameter to newJMXConnector contains the key jmx.remote.protocol.provider.pkgs then the associated value is the provider package list.
2. Otherwise, if the system property jmx.remote.protocol.provider.pkgs exists, then its value is the provider package list.
3. Otherwise, there is no provider package list.

The provider package list is a string that is interpreted as a list of non-empty Java package names separated by vertical bars (|). If the string is empty, then so is the provider package list. If the provider package list is not a String, or if it contains an element that is an empty string, a JMXProviderException is thrown.

If the provider package list exists and is not empty, then for each element pkg of the list, the factory will attempt to load the class

pkg.protocol.ClientProvider

If the environment parameter to newJMXConnector contains the key jmx.remote.protocol.provider.class.loader then the associated value is the class loader to use to load the provider. If the associated value is not an instance of ClassLoader, an IllegalArgumentException is thrown.

If the jmx.remote.protocol.provider.class.loader key is not present in the environment parameter, the calling thread's context class loader is used.

If the attempt to load this class produces a ClassNotFoundException, the search for a handler continues with the next element of the list.

Otherwise, a problem with the provider found is signalled by a JMXProviderException whose cause indicates the underlying exception, as follows:

• if the attempt to load the class produces an exception other than ClassNotFoundException, that is the cause;
• if Class.newInstance() for the class produces an exception, that is the cause.

If no provider is found by the above steps, including the default case where there is no provider package list, then the implementation will use its own provider for protocol, or it will throw a MalformedURLException if there is none. An implementation may choose to find providers by other means. For example, it may support service providers, where the service interface is JMXConnectorProvider.

Every implementation must support the RMI connector protocol with the default RMI transport, specified with string rmi.

Once a provider is found, the result of the newJMXConnector method is the result of calling newJMXConnector on the provider.

The Map parameter passed to the JMXConnectorProvider is a new read-only Map that contains all the entries that were in the environment parameter to JMXConnectorFactory.newJMXConnector, if there was one. Additionally, if the jmx.remote.protocol.provider.class.loader key is not present in the environment parameter, it is added to the new read-only Map. The associated value is the calling thread's context class loader.