Module java.base
Package java.security

Class Provider.Service

  • Enclosing class:
    Provider
    public static class Provider.Service
extends Object
    The description of a security service. It encapsulates the properties of a service and contains a factory method to obtain new implementation instances of this service.

    Each service has a provider that offers the service, a type, an algorithm name, and the name of the class that implements the service. Optionally, it also includes a list of alternate algorithm names for this service (aliases) and attributes, which are a map of (name, value) String pairs.

    This class defines the methods supportsParameter() and newInstance() which are used by the Java security framework when it searches for suitable services and instantiates them. The valid arguments to those methods depend on the type of service. For the service types defined within Java SE, see the Java Cryptography Architecture (JCA) Reference Guide for the valid values. Note that components outside of Java SE can define additional types of services and their behavior.

    Instances of this class are immutable.

    Since:
    1.5

    • Constructor Detail

      • Service

        public Service​(Provider provider,
               String type,
               String algorithm,
               String className,
               List<String> aliases,
               Map<String,​String> attributes)
        Construct a new service.
        Parameters:
        provider - the provider that offers this service
        type - the type of this service
        algorithm - the algorithm name
        className - the name of the class implementing this service
        aliases - List of aliases or null if algorithm has no aliases
        attributes - Map of attributes or null if this implementation has no attributes
        Throws:
        NullPointerException - if provider, type, algorithm, or className is null

    • Method Detail

      • getType

        public final String getType()
        Get the type of this service. For example, MessageDigest.
        Returns:
        the type of this service

      • getAlgorithm

        public final String getAlgorithm()
        Return the name of the algorithm of this service. For example, SHA-1.
        Returns:
        the algorithm of this service

      • getProvider

        public final Provider getProvider()
        Return the Provider of this service.
        Returns:
        the Provider of this service

      • getClassName

        public final String getClassName()
        Return the name of the class implementing this service.
        Returns:
        the name of the class implementing this service

      • getAttribute

        public final String getAttribute​(String name)
        Return the value of the specified attribute or null if this attribute is not set for this Service.
        Parameters:
        name - the name of the requested attribute
        Returns:
        the value of the specified attribute or null if the attribute is not present
        Throws:
        NullPointerException - if name is null

      • newInstance

        public Object newInstance​(Object constructorParameter)
                   throws NoSuchAlgorithmException
        Return a new instance of the implementation described by this service. The security provider framework uses this method to construct implementations. Applications will typically not need to call it.

        The default implementation uses reflection to invoke the standard constructor for this type of service. Security providers can override this method to implement instantiation in a different way. For details and the values of constructorParameter that are valid for the various types of services see the Java Cryptography Architecture (JCA) Reference Guide.

        Parameters:
        constructorParameter - the value to pass to the constructor, or null if this type of service does not use a constructorParameter.
        Returns:
        a new implementation of this service
        Throws:
        InvalidParameterException - if the value of constructorParameter is invalid for this type of service.
        NoSuchAlgorithmException - if instantiation failed for any other reason.

      • supportsParameter

        public boolean supportsParameter​(Object parameter)
        Test whether this Service can use the specified parameter. Returns false if this service cannot use the parameter. Returns true if this service can use the parameter, if a fast test is infeasible, or if the status is unknown.

        The security provider framework uses this method with some types of services to quickly exclude non-matching implementations for consideration. Applications will typically not need to call it.

        For details and the values of parameter that are valid for the various types of services see the top of this class and the Java Cryptography Architecture (JCA) Reference Guide. Security providers can override it to implement their own test.

        Parameters:
        parameter - the parameter to test
        Returns:
        false if this service cannot use the specified parameter; true if it can possibly use the parameter
        Throws:
        InvalidParameterException - if the value of parameter is invalid for this type of service or if this method cannot be used with this type of service

      • toString

        public String toString()
        Return a String representation of this service.
        Overrides:
        toString in class Object
        Returns:
        a String representation of this service.