GCMParameterSpec (moe.ios.core API)

java.lang.Object
- javax.crypto.spec.GCMParameterSpec

All Implemented Interfaces:

AlgorithmParameterSpec
```
public class GCMParameterSpec
extends Object
implements AlgorithmParameterSpec
```
Provides a the parameters for an instance of a Cipher using Galois/Counter Mode (GCM). This is an Authenticated Encryption with Associated Data (AEAD) mode for a cipher which allows you to use the Cipher.updateAAD(byte[]) method to provide data that is transmitted in the clear but authenticated using a cryptographic Message Authentication Code (MAC).

Since:

1.7

Constructor Summary

Constructors
Constructor	Description
`GCMParameterSpec(int tagLen, byte[] iv)`	Creates a new `GCMParameterSpec` instance from the specified Initial Vector (IV) from buffer `iv` and a tag length of `tagLen` in bits.
`GCMParameterSpec(int tagLen, byte[] iv, int offset, int byteCount)`	Creates a new `GCMParameterSpec` instance with the Initial Vector (IV) of `byteCount` bytes from the specified buffer `iv` starting at `offset` and a tag length of `tagLen` in bits.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`byte[]`	`getIV()`	Returns the Initial Vector (IV) used by this parameter spec.
`int`	`getTLen()`	Returns the size of the tag in bits.

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

- Constructor Detail
  - GCMParameterSpec
```
public GCMParameterSpec(int tagLen,
                        byte[] iv)
```
    Creates a new GCMParameterSpec instance from the specified Initial Vector (IV) from buffer iv and a tag length of tagLen in bits.
    
    Throws:
    
    IllegalArgumentException - if the specified iv is null or offset and byteCount do not specify a valid chunk in the specified buffer.
  - GCMParameterSpec
```
public GCMParameterSpec(int tagLen,
                        byte[] iv,
                        int offset,
                        int byteCount)
```
    Creates a new GCMParameterSpec instance with the Initial Vector (IV) of byteCount bytes from the specified buffer iv starting at offset and a tag length of tagLen in bits.
    
    Throws:
    
    IllegalArgumentException - if the specified iv is null or offset and byteCount do not specify a valid chunk in the specified buffer.
    
    ArrayIndexOutOfBoundsException - if offset or byteCount are negative.
- Method Detail
  - getTLen
```
public int getTLen()
```
    Returns the size of the tag in bits.
  - getIV
```
public byte[] getIV()
```
    Returns the Initial Vector (IV) used by this parameter spec.