Added in API level 1

java.security

Provides the classes and interfaces for the security framework. This includes classes that implement an easily configurable, fine-grained access control security architecture. This package also supports the generation and storage of cryptographic public key pairs, as well as a number of exportable cryptographic operations including those for message digest and signature generation. Finally, this package provides classes that support signed/guarded objects and secure random number generation. Many of the classes provided in this package (the cryptographic and secure random number generator classes in particular) are provider-based. The class itself defines a programming interface to which applications may write. The implementations themselves may then be written by independent third-party vendors and plugged in seamlessly as needed. Therefore application developers may take advantage of any number of provider-based implementations without having to add or rewrite code.

Package Specification

For further documentation, please see:

Interfaces

AlgorithmConstraints This interface specifies constraints for cryptographic algorithms, keys (key sizes), and other algorithm parameters. 
Certificate This interface was deprecated in API level 3. This class is deprecated and subject to removal in a future version of Java SE. It has been replaced by java.security.cert.Certificate and related classes. 
DomainCombiner Legacy security code; do not use. 
Guard

This interface represents a guard, which is an object that is used to protect access to another object. 

Key The Key interface is the top-level interface for all keys. 
KeyStore.Entry A marker interface for KeyStore entry types. 
KeyStore.Entry.Attribute An attribute associated with a keystore entry. 
KeyStore.LoadStoreParameter A marker interface for KeyStore load and store parameters. 
KeyStore.ProtectionParameter A marker interface for keystore protection parameters. 
Policy.Parameters  
Principal This interface represents the abstract notion of a principal, which can be used to represent any entity, such as an individual, a corporation, and a login id. 
PrivateKey A private key. 
PrivilegedAction<T> Android doesn't support SecurityManager. 
PrivilegedExceptionAction<T> Android doesn't support SecurityManager. 
PublicKey

A public key. 

SecureRandomParameters A marker interface for parameters used in various SecureRandom methods. 

Classes

AccessControlContext Android doesn't support SecurityManager. 
AccessController Android doesn't support SecurityManager. 
AlgorithmParameterGenerator The AlgorithmParameterGenerator class is used to generate a set of parameters to be used with a certain algorithm. 
AlgorithmParameterGeneratorSpi This class defines the Service Provider Interface (SPI) for the AlgorithmParameterGenerator class, which is used to generate a set of parameters to be used with a certain algorithm. 
AlgorithmParameters This class is used as an opaque representation of cryptographic parameters. 
AlgorithmParametersSpi This class defines the Service Provider Interface (SPI) for the AlgorithmParameters class, which is used to manage algorithm parameters. 
AllPermission Android doesn't support SecurityManager. 
AuthProvider Legacy security code; do not use. 
BasicPermission Android doesn't support SecurityManager. 
CodeSigner This class encapsulates information about a code signer. 
CodeSource Legacy security code; do not use. 
DigestInputStream A transparent stream that updates the associated message digest using the bits going through the stream. 
DigestOutputStream A transparent stream that updates the associated message digest using the bits going through the stream. 
DomainLoadStoreParameter Configuration data that specifies the keystores in a keystore domain. 
DrbgParameters This class specifies the parameters used by a DRBG (Deterministic Random Bit Generator). 
DrbgParameters.Instantiation DRBG parameters for instantiation. 
DrbgParameters.NextBytes DRBG parameters for random bits generation. 
DrbgParameters.Reseed DRBG parameters for reseed. 
GuardedObject A GuardedObject is an object that is used to protect access to another object. 
Identity This class was deprecated in API level 3. This class is deprecated and subject to removal in a future version of Java SE. It has been replaced by java.security.KeyStore, the java.security.cert package, and java.security.Principal. 
IdentityScope This class was deprecated in API level 3. This class is deprecated and subject to removal in a future version of Java SE. It has been replaced by java.security.KeyStore, the java.security.cert package, and java.security.Principal. 
KeyFactory Key factories are used to convert keys (opaque cryptographic keys of type Key) into key specifications (transparent representations of the underlying key material), and vice versa. 
KeyFactorySpi This class defines the Service Provider Interface (SPI) for the KeyFactory class. 
KeyPair This class is a simple holder for a key pair (a public key and a private key). 
KeyPairGenerator The KeyPairGenerator class is used to generate pairs of public and private keys. 
KeyPairGeneratorSpi

This class defines the Service Provider Interface (SPI) for the KeyPairGenerator class, which is used to generate pairs of public and private keys. 

KeyRep Standardized representation for serialized Key objects. 
KeyStore This class represents a storage facility for cryptographic keys and certificates. 
KeyStore.Builder A description of a to-be-instantiated KeyStore object. 
KeyStore.CallbackHandlerProtection A ProtectionParameter encapsulating a CallbackHandler. 
KeyStore.PasswordProtection A password-based implementation of ProtectionParameter. 
KeyStore.PrivateKeyEntry A KeyStore entry that holds a PrivateKey and corresponding certificate chain. 
KeyStore.SecretKeyEntry A KeyStore entry that holds a SecretKey. 
KeyStore.TrustedCertificateEntry A KeyStore entry that holds a trusted Certificate. 
KeyStoreSpi This class defines the Service Provider Interface (SPI) for the KeyStore class. 
MessageDigest This MessageDigest class provides applications the functionality of a message digest algorithm, such as SHA-1 or SHA-256. 
MessageDigestSpi This class defines the Service Provider Interface (SPI) for the MessageDigest class, which provides the functionality of a message digest algorithm, such as MD5 or SHA. 
Permission Android doesn't support SecurityManager. 
PermissionCollection Android doesn't support SecurityManager. 
Permissions Android doesn't support SecurityManager. 
PKCS12Attribute An attribute associated with a PKCS12 keystore entry. 
Policy Android doesn't support SecurityManager. 
PolicySpi This class defines the Service Provider Interface (SPI) for the Policy class. 
ProtectionDomain Legacy security code; do not use. 
Provider This class represents a "provider" for the Java Security API, where a provider implements some or all parts of Java Security. 
Provider.Service The description of a security service. 
SecureClassLoader This class extends ClassLoader with additional support for defining classes with an associated code source and permissions which are retrieved by the system policy by default. 
SecureRandom This class provides a cryptographically strong random number generator (RNG). 
SecureRandomSpi This class defines the Service Provider Interface (SPI) for the SecureRandom class. 
Security

This class centralizes all security properties and common security methods. 

SecurityPermission Legacy security code; do not use. 
Signature The Signature class is used to provide applications the functionality of a digital signature algorithm. 
SignatureSpi This class defines the Service Provider Interface (SPI) for the Signature class, which is used to provide the functionality of a digital signature algorithm. 
SignedObject

SignedObject is a class for the purpose of creating authentic runtime objects whose integrity cannot be compromised without being detected. 

Signer This class was deprecated in API level 3. This class is deprecated and subject to removal in a future version of Java SE. It has been replaced by java.security.KeyStore, the java.security.cert package, and java.security.Principal. 
Timestamp This class encapsulates information about a signed timestamp. 
UnresolvedPermission Legacy security code; do not use. 

Enums

CryptoPrimitive An enumeration of cryptographic primitives. 
DrbgParameters.Capability The reseedable and prediction resistance capabilities of a DRBG. 
KeyRep.Type Key type. 

Exceptions

AccessControlException

This exception is thrown by the AccessController to indicate that a requested access (to a critical system resource such as the file system or the network) is denied. 

DigestException This is the generic Message Digest exception. 
GeneralSecurityException The GeneralSecurityException class is a generic security exception class that provides type safety for all the security-related exception classes that extend from it. 
InvalidAlgorithmParameterException This is the exception for invalid or inappropriate algorithm parameters. 
InvalidKeyException This is the exception for invalid Keys (invalid encoding, wrong length, uninitialized, etc). 
InvalidParameterException This exception, designed for use by the JCA/JCE engine classes, is thrown when an invalid parameter is passed to a method. 
KeyException This is the basic key exception. 
KeyManagementException This is the general key management exception for all operations dealing with key management. 
KeyStoreException This is the generic KeyStore exception. 
NoSuchAlgorithmException This exception is thrown when a particular cryptographic algorithm is requested but is not available in the environment. 
NoSuchProviderException This exception is thrown when a particular security provider is requested but is not available in the environment. 
PrivilegedActionException Legacy security code; do not use. 
ProviderException A runtime exception for Provider exceptions (such as misconfiguration errors or unrecoverable internal errors), which may be subclassed by Providers to throw specialized, provider-specific runtime errors. 
SignatureException This is the generic Signature exception. 
UnrecoverableEntryException This exception is thrown if an entry in the keystore cannot be recovered. 
UnrecoverableKeyException This exception is thrown if a key in the keystore cannot be recovered.