NFACompiler (Flink : 2.0-SNAPSHOT API)

java.lang.Object
- org.apache.flink.cep.nfa.compiler.NFACompiler

```
public class NFACompiler
extends Object
```
Compiler class containing methods to compile a Pattern into a NFA or a NFACompiler.NFAFactory.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static interface NFACompiler.NFAFactory<T>
Factory interface for NFA.

Field Summary

Fields
Modifier and Type Field Description

protected static String ENDING_STATE_NAME

Constructor Summary

Constructors
Constructor Description

NFACompiler()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static boolean`	`canProduceEmptyMatches(Pattern<?,?> pattern)`	Verifies if the provided pattern can possibly generate empty match.
`static <T> NFACompiler.NFAFactory<T>`	`compileFactory(Pattern<T,?> pattern, boolean timeoutHandling)`	Compiles the given pattern into a `NFACompiler.NFAFactory`.

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

- Field Detail
  - ENDING_STATE_NAME
```
protected static final String ENDING_STATE_NAME
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - NFACompiler
```
public NFACompiler()
```
- Method Detail
  - compileFactory
```
public static <T> NFACompiler.NFAFactory<T> compileFactory(Pattern<T,?> pattern,
                                                           boolean timeoutHandling)
```
    Compiles the given pattern into a NFACompiler.NFAFactory. The NFA factory can be used to create multiple NFAs.
    
    Type Parameters:
    
    T - Type of the input events
    
    Parameters:
    
    pattern - Definition of sequence pattern
    
    timeoutHandling - True if the NFA shall return timed out event patterns
    
    Returns:
    
    Factory for NFAs corresponding to the given pattern
  - canProduceEmptyMatches
```
public static boolean canProduceEmptyMatches(Pattern<?,?> pattern)
```
    Verifies if the provided pattern can possibly generate empty match. Example of patterns that can possibly generate empty matches are: A*, A?, A* B? etc.
    
    Parameters:
    
    pattern - pattern to check
    
    Returns:
    
    true if empty match could potentially match the pattern, false otherwise