Provider (Java Platform SE 7 )

java.lang.Object
- java.util.Dictionary<K,V>
- - java.util.Hashtable<Object,Object>
  - - java.util.Properties
    - - java.security.Provider

All Implemented Interfaces:: Serializable, Cloneable, Map<Object,Object>

Direct Known Subclasses:: AuthProvider

public abstract class Provider
extends Properties

This class represents a "provider" for the Java Security API, where a provider implements some or all parts of Java Security. Services that a provider may implement include:

Algorithms (such as DSA, RSA, MD5 or SHA-1).
Key generation, conversion, and management facilities (such as for algorithm-specific keys).

Each provider has a name and a version number, and is configured in each runtime it is installed in.

See The Provider Class in the "Java Cryptography Architecture API Specification & Reference" for information about how a particular type of provider, the cryptographic service provider, works and is installed. However, please note that a provider can be used to implement any security service in Java that uses a pluggable architecture with a choice of implementations that fit underneath.

Some provider implementations may encounter unrecoverable internal errors during their operation, for example a failure to communicate with a security token. A ProviderException should be used to indicate such errors.

The service type Provider is reserved for use by the security framework. Services of this type cannot be added, removed, or modified by applications. The following attributes are automatically placed in each Provider object:

Name	Value
`Provider.id name`	`String.valueOf(provider.getName())`
`Provider.id version`	`String.valueOf(provider.getVersion())`
`Provider.id info`	`String.valueOf(provider.getInfo())`
`Provider.id className`	`provider.getClass().getName()`

See Also:: Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class Provider.Service
The description of a security service.

Nested Classes
Modifier and Type	Class and Description
`static class`	`Provider.Service` The description of a security service.

Field Summary
- Fields inherited from class java.util.Properties
  defaults

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`Provider(String name, double version, String info)` Constructs a provider with the specified name, version number, and information.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`clear()` Clears this provider so that it no longer contains the properties used to look up facilities implemented by the provider.
`Enumeration<Object>`	`elements()` Returns an enumeration of the values in this hashtable.
`Set<Map.Entry<Object,Object>>`	`entrySet()` Returns an unmodifiable Set view of the property entries contained in this Provider.
`Object`	`get(Object key)` Returns the value to which the specified key is mapped, or `null` if this map contains no mapping for the key.
`String`	`getInfo()` Returns a human-readable description of the provider and its services.
`String`	`getName()` Returns the name of this provider.
`String`	`getProperty(String key)` Searches for the property with the specified key in this property list.
`Provider.Service`	`getService(String type, String algorithm)` Get the service describing this Provider's implementation of the specified type of this algorithm or alias.
`Set<Provider.Service>`	`getServices()` Get an unmodifiable Set of all services supported by this Provider.
`double`	`getVersion()` Returns the version number for this provider.
`Enumeration<Object>`	`keys()` Returns an enumeration of the keys in this hashtable.
`Set<Object>`	`keySet()` Returns an unmodifiable Set view of the property keys contained in this provider.
`void`	`load(InputStream inStream)` Reads a property list (key and element pairs) from the input stream.
`Object`	`put(Object key, Object value)` Sets the `key` property to have the specified `value`.
`void`	`putAll(Map<?,?> t)` Copies all of the mappings from the specified Map to this provider.
`protected void`	`putService(Provider.Service s)` Add a service.
`Object`	`remove(Object key)` Removes the `key` property (and its corresponding `value`).
`protected void`	`removeService(Provider.Service s)` Remove a service previously added using `putService()`.
`String`	`toString()` Returns a string with the name and the version number of this provider.
`Collection<Object>`	`values()` Returns an unmodifiable Collection view of the property values contained in this provider.

Methods inherited from class java.util.Properties
getProperty, list, list, load, loadFromXML, propertyNames, save, setProperty, store, store, storeToXML, storeToXML, stringPropertyNames

Methods inherited from class java.util.Hashtable
clone, contains, containsKey, containsValue, equals, hashCode, isEmpty, rehash, size

Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - Provider
```
protected Provider(String name,
        double version,
        String info)
```
    Constructs a provider with the specified name, version number, and information.
    
    Parameters:
    name - the provider name.
    version - the provider version number.
    info - a description of the provider and its services.
- Method Detail
  - getName
```
public String getName()
```
    Returns the name of this provider.
    
    Returns:
    the name of this provider.
  - getVersion
```
public double getVersion()
```
    Returns the version number for this provider.
    
    Returns:
    the version number for this provider.
  - getInfo
```
public String getInfo()
```
    Returns a human-readable description of the provider and its services. This may return an HTML page, with relevant links.
    
    Returns:
    a description of the provider and its services.
  - toString
```
public String toString()
```
    Returns a string with the name and the version number of this provider.
    
    Overrides:
    
    toString in class Hashtable<Object,Object>
    
    Returns:
    the string with the name and the version number for this provider.
  - clear
```
public void clear()
```
    Clears this provider so that it no longer contains the properties used to look up facilities implemented by the provider.
    First, if there is a security manager, its checkSecurityAccess method is called with the string "clearProviderProperties."+name (where name is the provider name) to see if it's ok to clear this provider. If the default implementation of checkSecurityAccess is used (that is, that method is not overriden), then this results in a call to the security manager's checkPermission method with a SecurityPermission("clearProviderProperties."+name) permission.
    
    Specified by:
    
    clear in interface Map<Object,Object>
    
    Overrides:
    
    clear in class Hashtable<Object,Object>
    
    Throws:
    
    SecurityException - if a security manager exists and its SecurityManager.checkSecurityAccess(java.lang.String) method denies access to clear this provider
    Since:
    
    1.2
  - load
```
public void load(InputStream inStream)
          throws IOException
```
    Reads a property list (key and element pairs) from the input stream.
    
    Overrides:
    
    load in class Properties
    
    Parameters:
    inStream - the input stream.
    
    Throws:
    
    IOException - if an error occurred when reading from the input stream.
    See Also:
    Properties.load(java.io.Reader)
  - putAll
```
public void putAll(Map<?,?> t)
```
    Copies all of the mappings from the specified Map to this provider. These mappings will replace any properties that this provider had for any of the keys currently in the specified Map.
    
    Specified by:
    
    putAll in interface Map<Object,Object>
    
    Overrides:
    
    putAll in class Hashtable<Object,Object>
    
    Parameters:
    t - mappings to be stored in this map
    Since:
    
    1.2
  - entrySet
```
public Set<Map.Entry<Object,Object>> entrySet()
```
    Returns an unmodifiable Set view of the property entries contained in this Provider.
    
    Specified by:
    
    entrySet in interface Map<Object,Object>
    
    Overrides:
    
    entrySet in class Hashtable<Object,Object>
    
    Returns:
    a set view of the mappings contained in this map
    Since:
    
    1.2
    
    See Also:
    Map.Entry
  - keySet
```
public Set<Object> keySet()
```
    Returns an unmodifiable Set view of the property keys contained in this provider.
    
    Specified by:
    
    keySet in interface Map<Object,Object>
    
    Overrides:
    
    keySet in class Hashtable<Object,Object>
    
    Returns:
    a set view of the keys contained in this map
    Since:
    
    1.2
  - values
```
public Collection<Object> values()
```
    Returns an unmodifiable Collection view of the property values contained in this provider.
    
    Specified by:
    
    values in interface Map<Object,Object>
    
    Overrides:
    
    values in class Hashtable<Object,Object>
    
    Returns:
    a collection view of the values contained in this map
    Since:
    
    1.2
  - put
```
public Object put(Object key,
         Object value)
```
    Sets the key property to have the specified value.
    First, if there is a security manager, its checkSecurityAccess method is called with the string "putProviderProperty."+name, where name is the provider name, to see if it's ok to set this provider's property values. If the default implementation of checkSecurityAccess is used (that is, that method is not overriden), then this results in a call to the security manager's checkPermission method with a SecurityPermission("putProviderProperty."+name) permission.
    
    Specified by:
    
    put in interface Map<Object,Object>
    
    Overrides:
    
    put in class Hashtable<Object,Object>
    
    Parameters:
    key - the property key.
    value - the property value.
    
    Returns:
    the previous value of the specified property (key), or null if it did not have one.
    
    Throws:
    
    SecurityException - if a security manager exists and its SecurityManager.checkSecurityAccess(java.lang.String) method denies access to set property values.
    Since:
    
    1.2
    
    See Also:
    Object.equals(Object), Hashtable.get(Object)
  - remove
```
public Object remove(Object key)
```
    Removes the key property (and its corresponding value).
    First, if there is a security manager, its checkSecurityAccess method is called with the string "removeProviderProperty."+name, where name is the provider name, to see if it's ok to remove this provider's properties. If the default implementation of checkSecurityAccess is used (that is, that method is not overriden), then this results in a call to the security manager's checkPermission method with a SecurityPermission("removeProviderProperty."+name) permission.
    
    Specified by:
    
    remove in interface Map<Object,Object>
    
    Overrides:
    
    remove in class Hashtable<Object,Object>
    
    Parameters:
    key - the key for the property to be removed.
    
    Returns:
    the value to which the key had been mapped, or null if the key did not have a mapping.
    
    Throws:
    
    SecurityException - if a security manager exists and its SecurityManager.checkSecurityAccess(java.lang.String) method denies access to remove this provider's properties.
    Since:
    
    1.2
  - get
```
public Object get(Object key)
```
    Description copied from class: Hashtable
    
    Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.
    More formally, if this map contains a mapping from a key k to a value v such that (key.equals(k)), then this method returns v; otherwise it returns null. (There can be at most one such mapping.)
    
    Specified by:
    
    get in interface Map<Object,Object>
    
    Overrides:
    
    get in class Hashtable<Object,Object>
    
    Parameters:
    key - the key whose associated value is to be returned
    
    Returns:
    the value to which the specified key is mapped, or null if this map contains no mapping for the key
    See Also:
    Hashtable.put(Object, Object)
  - keys
```
public Enumeration<Object> keys()
```
    Description copied from class: Hashtable
    
    Returns an enumeration of the keys in this hashtable.
    
    Overrides:
    
    keys in class Hashtable<Object,Object>
    
    Returns:
    an enumeration of the keys in this hashtable.
    See Also:
    Enumeration, Hashtable.elements(), Hashtable.keySet(), Map
  - elements
```
public Enumeration<Object> elements()
```
    Description copied from class: Hashtable
    
    Returns an enumeration of the values in this hashtable. Use the Enumeration methods on the returned object to fetch the elements sequentially.
    
    Overrides:
    
    elements in class Hashtable<Object,Object>
    
    Returns:
    an enumeration of the values in this hashtable.
    See Also:
    Enumeration, Hashtable.keys(), Hashtable.values(), Map
  - getProperty
```
public String getProperty(String key)
```
    Description copied from class: Properties
    
    Searches for the property with the specified key in this property list. If the key is not found in this property list, the default property list, and its defaults, recursively, are then checked. The method returns null if the property is not found.
    
    Overrides:
    
    getProperty in class Properties
    
    Parameters:
    key - the property key.
    
    Returns:
    the value in this property list with the specified key value.
    See Also:
    Properties.setProperty(java.lang.String, java.lang.String), Properties.defaults
  - getService
```
public Provider.Service getService(String type,
                          String algorithm)
```
    Get the service describing this Provider's implementation of the specified type of this algorithm or alias. If no such implementation exists, this method returns null. If there are two matching services, one added to this provider using putService() and one added via put(), the service added via putService() is returned.
    
    Parameters:
    type - the type of service requested (for example, MessageDigest)
    algorithm - the case insensitive algorithm name (or alternate alias) of the service requested (for example, SHA-1)
    
    Returns:
    the service describing this Provider's matching service or null if no such service exists
    
    Throws:
    
    NullPointerException - if type or algorithm is null
    Since:
    
    1.5
  - getServices
```
public Set<Provider.Service> getServices()
```
    Get an unmodifiable Set of all services supported by this Provider.
    
    Returns:
    an unmodifiable Set of all services supported by this Provider
    Since:
    
    1.5
  - putService
```
protected void putService(Provider.Service s)
```
    Add a service. If a service of the same type with the same algorithm name exists and it was added using putService(), it is replaced by the new service. This method also places information about this service in the provider's Hashtable values in the format described in the Java Cryptography Architecture API Specification & Reference .
    Also, if there is a security manager, its checkSecurityAccess method is called with the string "putProviderProperty."+name, where name is the provider name, to see if it's ok to set this provider's property values. If the default implementation of checkSecurityAccess is used (that is, that method is not overriden), then this results in a call to the security manager's checkPermission method with a SecurityPermission("putProviderProperty."+name) permission.
    
    Parameters:
    s - the Service to add
    
    Throws:
    
    SecurityException - if a security manager exists and its SecurityManager.checkSecurityAccess(java.lang.String) method denies access to set property values.
    
    NullPointerException - if s is null
    Since:
    
    1.5
  - removeService
```
protected void removeService(Provider.Service s)
```
    Remove a service previously added using putService(). The specified service is removed from this provider. It will no longer be returned by getService() and its information will be removed from this provider's Hashtable.
    Also, if there is a security manager, its checkSecurityAccess method is called with the string "removeProviderProperty."+name, where name is the provider name, to see if it's ok to remove this provider's properties. If the default implementation of checkSecurityAccess is used (that is, that method is not overriden), then this results in a call to the security manager's checkPermission method with a SecurityPermission("removeProviderProperty."+name) permission.
    
    Parameters:
    s - the Service to be removed
    
    Throws:
    
    SecurityException - if a security manager exists and its SecurityManager.checkSecurityAccess(java.lang.String) method denies access to remove this provider's properties.
    
    NullPointerException - if s is null
    Since:
    
    1.5

Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2019, Oracle and/or its affiliates. All rights reserved.

Class Provider

Nested Class Summary

Field Summary

Fields inherited from class java.util.Properties

Constructor Summary

Method Summary

Methods inherited from class java.util.Properties

Methods inherited from class java.util.Hashtable

Methods inherited from class java.lang.Object

Constructor Detail

Provider

Method Detail

getName

getVersion

getInfo

toString

clear

load

putAll

entrySet

keySet

values

put

remove

get

keys

elements

getProperty

getService

getServices

putService

removeService