DatawithDSA (IBMJCECCA Class Documentation)

java.lang.Object
- java.security.SignatureSpi
- - com.ibm.crypto.hdwrCCA.provider.DatawithDSA

```
public class DatawithDSA
extends java.security.SignatureSpi
```
This class is a concrete DSA signing with data implementation of the Service Provider Interface (SPI) for the Signature class, which is used to provide the functionality of a digital signature algorithm.
This documentation is provided for implementation insight only. This class is not intended to be called directly by application developers. Please consult the 'Java Cryptography Architecture Standard' for details on how to use this interface through a public standard class.

Field Summary
- Fields inherited from class java.security.SignatureSpi
  appRandom

Constructor Summary

Constructors
Constructor and Description

DatawithDSA()
Constructs a new instance of this class.

Constructors
Constructor and Description
`DatawithDSA()` Constructs a new instance of this class.

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`protected java.lang.Object`	`engineGetParameter(java.lang.String param)` Deprecated.
`protected void`	`engineInitSign(java.security.PrivateKey privateKey)` Initializes this signature object with the specified private key for signing operations.
`protected void`	`engineInitVerify(java.security.PublicKey publicKey)` Initializes this signature object with the specified public key for verification operations.
`protected void`	`engineSetParameter(java.lang.String param, java.lang.Object value)` Deprecated.
`protected byte[]`	`engineSign()` Returns the signature bytes of all the data updated so far.
`protected void`	`engineUpdate(byte b)` Updates the data to be signed or verified using the specified byte.
`protected void`	`engineUpdate(byte[] buffer, int offset, int length)` Updates the data to be signed or verified, using the specified array of bytes, starting at the specified offset.
`protected boolean`	`engineVerify(byte[] sigBytes)` Verifies the passed-in signature.
`java.lang.String`	`toString()` returns a string containing a concise, human-readable description of this signature class.

Methods inherited from class java.security.SignatureSpi
clone, engineGetParameters, engineInitSign, engineSetParameter, engineSign, engineUpdate, engineVerify

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

- Constructor Detail
  - DatawithDSA
```
public DatawithDSA()
            throws java.security.NoSuchAlgorithmException,
                   java.security.NoSuchProviderException
```
    Constructs a new instance of this class.
    
    Throws:
    
    java.security.NoSuchAlgorithmException
    
    java.security.NoSuchProviderException
- Method Detail
  - engineGetParameter
```
protected java.lang.Object engineGetParameter(java.lang.String param)
                                       throws java.lang.UnsupportedOperationException
```
    Deprecated.
    
    Gets the value of the specified algorithm parameter. Please note that this method has no meaning for this provider, and has been deprecated.
    
    Specified by:
    
    engineGetParameter in class java.security.SignatureSpi
    
    Parameters:
    
    param - the string name of the parameter
    
    Throws:
    
    java.lang.UnsupportedOperationException - is always thrown.
  - engineInitSign
```
protected void engineInitSign(java.security.PrivateKey privateKey)
                       throws java.security.InvalidKeyException
```
    Initializes this signature object with the specified private key for signing operations.
    
    Specified by:
    
    engineInitSign in class java.security.SignatureSpi
    
    Parameters:
    
    privateKey - the private key of the identity whose signature will be generated
    
    Throws:
    
    java.security.InvalidKeyException - if the specified key is not a valid DSA private key (improperly encoded, parameters missing, etc).
  - engineInitVerify
```
protected void engineInitVerify(java.security.PublicKey publicKey)
                         throws java.security.InvalidKeyException
```
    Initializes this signature object with the specified public key for verification operations.
    
    Specified by:
    
    engineInitVerify in class java.security.SignatureSpi
    
    Parameters:
    
    publicKey - the public key of the identity whose signature is going to be verified
    
    Throws:
    
    java.security.InvalidKeyException - if the specified key is not a valid DSA public key (improperly encoded, parameters missing, etc).
  - engineSetParameter
```
protected void engineSetParameter(java.lang.String param,
                                  java.lang.Object value)
                           throws java.lang.UnsupportedOperationException
```
    Deprecated.
    
    Sets the specified algorithm parameter to the specified value. Please note that this method has no meaning for this provider and has been deprecated.
    
    Specified by:
    
    engineSetParameter in class java.security.SignatureSpi
    
    Throws:
    
    java.lang.UnsupportedOperationException - is always thrown.
  - engineSign
```
protected byte[] engineSign()
                     throws java.security.SignatureException
```
    Returns the signature bytes of all the data updated so far.
    
    Specified by:
    
    engineSign in class java.security.SignatureSpi
    
    Returns:
    
    the signature bytes of the signing operation's result.
    
    Throws:
    
    java.security.SignatureException - if the engine is not initialized properly or if this signature algorithm is unable to process the input data provided.
  - engineUpdate
```
protected void engineUpdate(byte b)
                     throws java.security.SignatureException
```
    Updates the data to be signed or verified using the specified byte.
    
    Specified by:
    
    engineUpdate in class java.security.SignatureSpi
    
    Parameters:
    
    b - the byte to use for the update
    
    Throws:
    
    java.security.SignatureException - if the engine is not initialized properly.
  - engineUpdate
```
protected void engineUpdate(byte[] buffer,
                            int offset,
                            int length)
                     throws java.security.SignatureException
```
    Updates the data to be signed or verified, using the specified array of bytes, starting at the specified offset.
    
    Specified by:
    
    engineUpdate in class java.security.SignatureSpi
    
    Parameters:
    
    buffer - the array of bytes
    
    offset - the offset to start from in the array of bytes
    
    length - the number of bytes to use, starting at offset
    
    Throws:
    
    java.security.SignatureException - if the engine is not initialized properly
  - engineVerify
```
protected boolean engineVerify(byte[] sigBytes)
                        throws java.security.SignatureException
```
    Verifies the passed-in signature.
    
    Specified by:
    
    engineVerify in class java.security.SignatureSpi
    
    Parameters:
    
    sigBytes - the signature bytes to be verified
    
    Returns:
    
    true if the signature was verified, false if not.
    
    Throws:
    
    java.security.SignatureException - if the engine is not initialized properly, the passed-in signature is improperly encoded or of the wrong type, if this signature algorithm is unable to process the input data provided, etc.
  - toString
```
public java.lang.String toString()
```
    returns a string containing a concise, human-readable description of this signature class.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    a printable representation of this signature class.

Fields inherited from class java.security.SignatureSpi

Methods inherited from class java.security.SignatureSpi

Methods inherited from class java.lang.Object

DatawithDSA

engineGetParameter

engineInitSign

engineInitVerify

engineSetParameter

engineSign

engineUpdate

engineUpdate

engineVerify

toString