ProductionPatternAlternative (Grammatica 1.6 Documentation)

java.lang.Object
- net.percederberg.grammatica.parser.ProductionPatternAlternative

```
public class ProductionPatternAlternative
extends java.lang.Object
```
A production pattern alternative. This class represents a list of production pattern elements. In order to provide productions that cannot be represented with the element occurance counters, multiple alternatives must be created and added to the same production pattern. A production pattern alternative is always contained within a production pattern.

Constructor Summary

Constructors
Constructor and Description

ProductionPatternAlternative()

Constructors
Constructor and Description
`ProductionPatternAlternative()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addElement(ProductionPatternElement elem)` Adds a production pattern element to this alternative.
`void`	`addElement(ProductionPatternElement elem, int min, int max)` Adds a production pattern element to this alternative.
`void`	`addProduction(int id, int min, int max)` Adds a production to this alternative.
`void`	`addToken(int id, int min, int max)` Adds a token to this alternative.
`boolean`	`equals(java.lang.Object obj)` Checks if this object is equal to another.
`ProductionPatternElement`	`getElement(int pos)` Returns an element in this alternative.
`int`	`getElementCount()` Returns the number of elements in this alternative.
`int`	`getMaxElementCount()` Returns the maximum number of elements needed to satisfy this alternative.
`int`	`getMinElementCount()` Returns the minimum number of elements needed to satisfy this alternative.
`ProductionPattern`	`getPattern()` Returns the production pattern containing this alternative.
`int`	`hashCode()` Returns a hash code for this object.
`boolean`	`isLeftRecursive()` Checks if this alternative is recursive on the left-hand side.
`boolean`	`isMatchingEmpty()` Checks if this alternative would match an empty stream of tokens.
`boolean`	`isRightRecursive()` Checks if this alternative is recursive on the right-hand side.
`java.lang.String`	`toString()` Returns a string representation of this object.

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

- Constructor Detail
  - ProductionPatternAlternative
```
public ProductionPatternAlternative()
```
- Method Detail
  - isLeftRecursive
```
public boolean isLeftRecursive()
```
    Checks if this alternative is recursive on the left-hand side. This method checks all the possible left side elements and returns true if the pattern itself is among them.
    
    Returns:
    
    true if the alternative is left side recursive, or false otherwise
  - isRightRecursive
```
public boolean isRightRecursive()
```
    Checks if this alternative is recursive on the right-hand side. This method checks all the possible right side elements and returns true if the pattern itself is among them.
    
    Returns:
    
    true if the alternative is right side recursive, or false otherwise
  - isMatchingEmpty
```
public boolean isMatchingEmpty()
```
    Checks if this alternative would match an empty stream of tokens. This check is equivalent of getMinElementCount() returning zero (0).
    
    Returns:
    
    true if the rule can match an empty token stream, or false otherwise
  - getPattern
```
public ProductionPattern getPattern()
```
    Returns the production pattern containing this alternative.
    
    Returns:
    
    the production pattern for this alternative
  - getElementCount
```
public int getElementCount()
```
    Returns the number of elements in this alternative.
    
    Returns:
    
    the number of elements in this alternative
  - getMinElementCount
```
public int getMinElementCount()
```
    Returns the minimum number of elements needed to satisfy this alternative. The value returned is the sum of all the elements minimum count.
    
    Returns:
    
    the minimum number of elements
  - getMaxElementCount
```
public int getMaxElementCount()
```
    Returns the maximum number of elements needed to satisfy this alternative. The value returned is the sum of all the elements maximum count.
    
    Returns:
    
    the maximum number of elements
  - getElement
```
public ProductionPatternElement getElement(int pos)
```
    Returns an element in this alternative.
    
    Parameters:
    
    pos - the element position, starting at 0
    
    Returns:
    
    the element found
  - addToken
```
public void addToken(int id,
                     int min,
                     int max)
```
    Adds a token to this alternative. The token is appended to the end of the element list. The multiplicity values specified define if the token is optional or required, and if it can be repeated.
    
    Parameters:
    
    id - the token (pattern) id
    
    min - the minimum number of occurancies
    
    max - the maximum number of occurancies, or -1 for infinite
  - addProduction
```
public void addProduction(int id,
                          int min,
                          int max)
```
    Adds a production to this alternative. The production is appended to the end of the element list. The multiplicity values specified define if the production is optional or required, and if it can be repeated.
    
    Parameters:
    
    id - the production (pattern) id
    
    min - the minimum number of occurancies
    
    max - the maximum number of occurancies, or -1 for infinite
  - addElement
```
public void addElement(ProductionPatternElement elem)
```
    Adds a production pattern element to this alternative. The element is appended to the end of the element list.
    
    Parameters:
    
    elem - the production pattern element
  - addElement
```
public void addElement(ProductionPatternElement elem,
                       int min,
                       int max)
```
    Adds a production pattern element to this alternative. The multiplicity values in the element will be overridden with the specified values. The element is appended to the end of the element list.
    
    Parameters:
    
    elem - the production pattern element
    
    min - the minimum number of occurancies
    
    max - the maximum number of occurancies, or -1 for infinite
  - equals
```
public boolean equals(java.lang.Object obj)
```
    Checks if this object is equal to another. This method only returns true for another production pattern alternative with identical elements in the same order.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    
    obj - the object to compare with
    
    Returns:
    
    true if the object is identical to this one, or false otherwise
  - hashCode
```
public int hashCode()
```
    Returns a hash code for this object.
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    
    a hash code for this object
  - toString
```
public java.lang.String toString()
```
    Returns a string representation of this object.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    a token string representation

Class ProductionPatternAlternative

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ProductionPatternAlternative

Method Detail

isLeftRecursive

isRightRecursive

isMatchingEmpty

getPattern

getElementCount

getMinElementCount

getMaxElementCount

getElement

addToken

addProduction

addElement

addElement

equals

hashCode

toString