Group (math 3.1.2 API)

All Superinterfaces:

Representable, RepresentationRestorer, StandaloneRepresentable, Structure

All Known Implementing Classes:

BasicGroup, DebugGroup, LazyGroup, ProductGroup, RingGroup, Secp256k1, Secp256k1Basic
```
public interface Group
extends Structure, RepresentationRestorer
```
An algebraic group.
Usually used as a wrapper around a GroupImpl to offer additional evaluation capabilities. You should use GroupImpl for your implementation instead.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`default GroupElementExpression`	`expr()` Returns a GroupElementExpression containing the neutral group element.
`default GroupElement`	`getGenerator()` Returns any generator of this group if the group is cyclic and it's feasible to compute a generator.
`GroupElement`	`getNeutralElement()` Returns the neutral element for this group
`GroupElement`	`getUniformlyRandomElement()` Returns an element of this structure that is drawn uniformly at random using a cryptographically strong RNG.
`default GroupElementVector`	`getUniformlyRandomElements(int n)` Returns n elements of this structure that are drawn uniformly and independently at random using a cryptographically strong RNG.
`default Zn.ZnElement`	`getUniformlyRandomExponent()` Returns a random integer between `0` and `size()-1` (inclusive) using a cryptographically strong RNG.
`default RingElementVector`	`getUniformlyRandomExponents(int n)` Returns n random integers between `0` and `size()-1` (inclusive) using a cryptographically strong RNG.
`default GroupElement`	`getUniformlyRandomNonNeutral()` Generates a uniformly random non-neutral element of this group using a cryptographically strong RNG.
`default GroupElementVector`	`getUniformlyRandomNonNeutrals(int n)` Generates `n` uniformly random non-neutral element of this group using a cryptographically strong RNG.
`default Zn.ZnElement`	`getUniformlyRandomNonzeroExponent()` Returns a random integer between `1` and `size()-1` (inclusive) using a cryptographically strong RNG.
`default RingElementVector`	`getUniformlyRandomNonzeroExponents(int n)` Returns n random integers between `1` and `size()-1` (inclusive) using a cryptographically strong RNG.
`default Zn.ZnElement`	`getUniformlyRandomUnitExponent()` Returns a random integer invertible mod `size()` using a cryptographically strong RNG.
`default RingElementVector`	`getUniformlyRandomUnitExponents(int n)` Returns n random integers invertible mod `size()` using a cryptographically strong RNG.
`default Zn`	`getZn()` Returns `Zn`, where `n == size()`.
`boolean`	`isCommutative()` Returns true if this group is known to be commutative.
`GroupElement`	`restoreElement(Representation repr)` Creates an element of this structure from its representation.
`default java.lang.Object`	`restoreFromRepresentation(java.lang.reflect.Type type, Representation repr)` Takes a representation and creates an object of the given type from it if the type is supported by the restorer.
`default GroupElementVector`	`restoreVector(Representation repr)` Restores a `GroupElementVector` containing group elements from this `Group` from a `Representation` of that vector.

Methods inherited from interface org.cryptimeleon.math.structures.Structure
getUniqueByteLength, hasPrimeSize, size

Methods inherited from interface org.cryptimeleon.math.serialization.Representable
getRepresentation

- Method Detail
  - getNeutralElement
```
GroupElement getNeutralElement()
```
    Returns the neutral element for this group
  - getUniformlyRandomElement
```
GroupElement getUniformlyRandomElement()
                                throws java.lang.UnsupportedOperationException
```
    Description copied from interface: Structure
    
    Returns an element of this structure that is drawn uniformly at random using a cryptographically strong RNG.
    
    Specified by:
    
    getUniformlyRandomElement in interface Structure
    
    Throws:
    
    java.lang.UnsupportedOperationException - if the operation is not supported
  - getUniformlyRandomElements
```
default GroupElementVector getUniformlyRandomElements(int n)
                                               throws java.lang.UnsupportedOperationException
```
    Description copied from interface: Structure
    
    Returns n elements of this structure that are drawn uniformly and independently at random using a cryptographically strong RNG.
    
    Specified by:
    
    getUniformlyRandomElements in interface Structure
    
    Throws:
    
    java.lang.UnsupportedOperationException - if the operation is not supported
  - getUniformlyRandomNonNeutral
```
default GroupElement getUniformlyRandomNonNeutral()
```
    Generates a uniformly random non-neutral element of this group using a cryptographically strong RNG.
  - getUniformlyRandomNonNeutrals
```
default GroupElementVector getUniformlyRandomNonNeutrals(int n)
```
    Generates n uniformly random non-neutral element of this group using a cryptographically strong RNG.
  - restoreElement
```
GroupElement restoreElement(Representation repr)
```
    Description copied from interface: Structure
    
    Creates an element of this structure from its representation.
    
    Specified by:
    
    restoreElement in interface Structure
    
    Parameters:
    
    repr - the Representation returned by Representable.getRepresentation()
    
    Returns:
    
    the decoded element corresponding to the representation
  - restoreVector
```
default GroupElementVector restoreVector(Representation repr)
```
    Restores a GroupElementVector containing group elements from this Group from a Representation of that vector.
    
    Parameters:
    
    repr - a representation of a GroupElementVector (obtained via GroupElementVector.getRepresentation()).
  - getGenerator
```
default GroupElement getGenerator()
                           throws java.lang.UnsupportedOperationException
```
    Returns any generator of this group if the group is cyclic and it's feasible to compute a generator.
    Repeated calls may or may not always supply the same generator again (i.e. the output is not guaranteed to be random)!
    
    Throws:
    
    java.lang.UnsupportedOperationException - if the group doesn't know or have a generator
  - isCommutative
```
boolean isCommutative()
```
    Returns true if this group is known to be commutative.
  - expr
```
default GroupElementExpression expr()
```
    Returns a GroupElementExpression containing the neutral group element.
  - restoreFromRepresentation
```
default java.lang.Object restoreFromRepresentation(java.lang.reflect.Type type,
                                                   Representation repr)
```
    Description copied from interface: RepresentationRestorer
    
    Takes a representation and creates an object of the given type from it if the type is supported by the restorer.
    
    Specified by:
    
    restoreFromRepresentation in interface RepresentationRestorer
    
    Parameters:
    
    type - tells the restorer which type the restored object should have
    
    repr - the representation to restore the object from
    
    Returns:
    
    the restored object
  - getZn
```
default Zn getZn()
```
    Returns Zn, where n == size().
  - getUniformlyRandomExponent
```
default Zn.ZnElement getUniformlyRandomExponent()
```
    Returns a random integer between 0 and size()-1 (inclusive) using a cryptographically strong RNG.
  - getUniformlyRandomExponents
```
default RingElementVector getUniformlyRandomExponents(int n)
```
    Returns n random integers between 0 and size()-1 (inclusive) using a cryptographically strong RNG.
  - getUniformlyRandomUnitExponent
```
default Zn.ZnElement getUniformlyRandomUnitExponent()
```
    Returns a random integer invertible mod size() using a cryptographically strong RNG.
  - getUniformlyRandomUnitExponents
```
default RingElementVector getUniformlyRandomUnitExponents(int n)
```
    Returns n random integers invertible mod size() using a cryptographically strong RNG.
  - getUniformlyRandomNonzeroExponent
```
default Zn.ZnElement getUniformlyRandomNonzeroExponent()
```
    Returns a random integer between 1 and size()-1 (inclusive) using a cryptographically strong RNG.
  - getUniformlyRandomNonzeroExponents
```
default RingElementVector getUniformlyRandomNonzeroExponents(int n)
```
    Returns n random integers between 1 and size()-1 (inclusive) using a cryptographically strong RNG.

Interface Group

Method Summary

Methods inherited from interface org.cryptimeleon.math.structures.Structure

Methods inherited from interface org.cryptimeleon.math.serialization.Representable

Method Detail

getNeutralElement

getUniformlyRandomElement

getUniformlyRandomElements

getUniformlyRandomNonNeutral

getUniformlyRandomNonNeutrals

restoreElement

restoreVector

getGenerator

isCommutative

expr

restoreFromRepresentation

getZn

getUniformlyRandomExponent

getUniformlyRandomExponents

getUniformlyRandomUnitExponent

getUniformlyRandomUnitExponents

getUniformlyRandomNonzeroExponent

getUniformlyRandomNonzeroExponents