Module java.base

Package javax.security.auth

Class Subject

java.lang.Object

javax.security.auth.Subject

All Implemented Interfaces:

Serializable

public final class Subject
extends Object
implements Serializable

A Subject represents a grouping of related information for a single entity, such as a person. Such information includes the Subject's identities as well as its security-related attributes (passwords and cryptographic keys, for example).

Subjects may potentially have multiple identities. Each identity is represented as a Principal within the Subject. Principals simply bind names to a Subject. For example, a Subject that happens to be a person, Alice, might have two Principals: one which binds "Alice Bar", the name on her driver license, to the Subject, and another which binds, "999-99-9999", the number on her student identification card, to the Subject. Both Principals refer to the same Subject even though each has a different name.

A Subject may also own security-related attributes, which are referred to as credentials. Sensitive credentials that require special protection, such as private cryptographic keys, are stored within a private credential Set. Credentials intended to be shared, such as public key certificates or Kerberos server tickets are stored within a public credential Set. Different permissions are required to access and modify the different credential Sets.

To retrieve all the Principals associated with a Subject, invoke the getPrincipals method. To retrieve all the public or private credentials belonging to a Subject, invoke the getPublicCredentials method or getPrivateCredentials method, respectively. To modify the returned Set of Principals and credentials, use the methods defined in the Set class. For example:

      Subject subject;
      Principal principal;
      Object credential;

      // add a Principal and credential to the Subject
      subject.getPrincipals().add(principal);
      subject.getPublicCredentials().add(credential);
 

This Subject class implements Serializable. While the Principals associated with the Subject are serialized, the credentials associated with the Subject are not. Note that the java.security.Principal class does not implement Serializable. Therefore all concrete Principal implementations associated with Subjects must implement Serializable.

Since:

1.4

See Also:

• Principal
• DomainCombiner
• Serialized Form

Constructor Summary

Constructors

Constructor	Description
Subject()	Create an instance of a Subject with an empty Set of Principals and empty Sets of public and private credentials.
Subject(boolean readOnly, Set<? extends Principal> principals, Set<?> pubCredentials, Set<?> privCredentials)	Create an instance of a Subject with Principals and credentials.

Method Summary

Modifier and Type

Method

Description

static <T> T

callAs(Subject subject, Callable<T> action)

Executes a Callable with subject as the current subject.

static Subject

current()

Returns the current subject.

static <T> T

doAs(Subject subject, PrivilegedAction<T> action)

Deprecated, for removal: This API element is subject to removal in a future version.

This method depends on AccessControlContext which, in conjunction with the Security Manager, is deprecated and subject to removal in a future release.

static <T> T

doAs(Subject subject, PrivilegedExceptionAction<T> action)

Deprecated, for removal: This API element is subject to removal in a future version.

This method depends on AccessControlContext which, in conjunction with the Security Manager, is deprecated and subject to removal in a future release.

static <T> T

doAsPrivileged(Subject subject, PrivilegedAction<T> action, AccessControlContext acc)

Deprecated, for removal: This API element is subject to removal in a future version.

This method is only useful in conjunction with the Security Manager, which is deprecated and subject to removal in a future release.

static <T> T

doAsPrivileged(Subject subject, PrivilegedExceptionAction<T> action, AccessControlContext acc)

Deprecated, for removal: This API element is subject to removal in a future version.

This method is only useful in conjunction with the Security Manager, which is deprecated and subject to removal in a future release.

boolean

equals(Object o)

Compares the specified Object with this Subject for equality.

Set<Principal>

getPrincipals()

Return the Set of Principals associated with this Subject.

<T extends Principal>
Set<T>

getPrincipals(Class<T> c)

Return a Set of Principals associated with this Subject that are instances or subclasses of the specified Class.

Set<Object>

getPrivateCredentials()

Return the Set of private credentials held by this Subject.

<T> Set<T>

getPrivateCredentials(Class<T> c)

Return a Set of private credentials associated with this Subject that are instances or subclasses of the specified Class.

Set<Object>

getPublicCredentials()

Return the Set of public credentials held by this Subject.

<T> Set<T>

getPublicCredentials(Class<T> c)

Return a Set of public credentials associated with this Subject that are instances or subclasses of the specified Class.

static Subject

getSubject(