ec.rule
Class Rule

java.lang.Object
  |
  +--ec.rule.Rule
All Implemented Interfaces:
java.lang.Cloneable, Prototype, java.io.Serializable, Setup, SortComparator

public abstract class Rule
extends java.lang.Object
implements Prototype, SortComparator

Rule is an abstract class for describing rules. It is abstract because it is supposed to be extended by different classes modelling different kinds of rules. It provides the reset abstract method for randomizing the individual. It also provides the mutate function for mutating an individual rule It also provides the clone function for cloning the rule.

You will need to implement some kind of artificial ordering between rules in a ruleset (the lt and gt methods inherited from SortComparator) so the ruleset can be sorted in such a way that it can be compared with another ruleset for equality. You should also implement hashCode and equals in such a way that they aren't based on pointer information, but on actual internal features.

Every rule points to a RuleConstraints which handles information that Rule shares with all the other Rules in a RuleSet.

Parameters
base.constraints
string
(name of the rule constraint)

Default Base
rule.rule

See Also:
Serialized Form

Field Summary
 byte constraints
          An index to a RuleConstraints
static java.lang.String P_CONSTRAINTS
           
static java.lang.String P_RULE
           
 
Constructor Summary
Rule()
           
 
Method Summary
 RuleConstraints constraints()
           
 Parameter defaultBase()
          Returns the default base for this prototype.
abstract  boolean equals(java.lang.Object other)
          Unlike the standard form for Java, this function should return true if this rule is "genetically identical" to the other rule.
abstract  int hashCode()
          Generates a hash code for this rule -- the rule for this is that the hash code must be the same for two rules that are equal to each other genetically.
 void mutate(EvolutionState state, int thread)
          Mutate the rule.
 void printRule(EvolutionState state, int log, int verbosity)
          Prints the rule in a way that can be read by readRule().
 void printRule(EvolutionState state, java.io.PrintWriter writer)
          Prints the rule in a way that can be read by readRule().
 void printRuleForHumans(EvolutionState state, int log, int verbosity)
          Nice printing.
 java.lang.String printRuleToString(EvolutionState state)
          Deprecated.  
 java.lang.Object protoClone()
          Creates a new individual cloned from a prototype, and suitable to begin use in its own evolutionary context.
 java.lang.Object protoCloneSimple()
          This should be implemented in a the top-level Prototype ONLY; in fact, it should probably be declared final.
 void readRule(EvolutionState state, java.io.LineNumberReader reader)
          Reads a rule printed by printRule(...).
 void readRuleFromString(java.lang.String string, EvolutionState state)
          Reads a rule from a string, which may contain a final '\n'.
abstract  void reset(EvolutionState state, int thread)
          The reset method randomly reinitializes the rule.
 void setup(EvolutionState state, Parameter base)
          Sets up the object by reading it from the parameters stored in state, built off of the parameter base base.
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface ec.util.SortComparator
gt, lt
 

Field Detail

P_RULE

public static final java.lang.String P_RULE

P_CONSTRAINTS

public static final java.lang.String P_CONSTRAINTS

constraints

public byte constraints
An index to a RuleConstraints
Constructor Detail

Rule

public Rule()
Method Detail

constraints

public final RuleConstraints constraints()

hashCode

public abstract int hashCode()
Generates a hash code for this rule -- the rule for this is that the hash code must be the same for two rules that are equal to each other genetically.
Overrides:
hashCode in class java.lang.Object

equals

public abstract boolean equals(java.lang.Object other)
Unlike the standard form for Java, this function should return true if this rule is "genetically identical" to the other rule.
Overrides:
equals in class java.lang.Object

reset

public abstract void reset(EvolutionState state,
                           int thread)
The reset method randomly reinitializes the rule.

mutate

public void mutate(EvolutionState state,
                   int thread)
Mutate the rule. The default form just resets the rule.

printRuleForHumans

public void printRuleForHumans(EvolutionState state,
                               int log,
                               int verbosity)
Nice printing. The default form simply calls printRule, but you might want to override this.

printRuleToString

public java.lang.String printRuleToString(EvolutionState state)
Deprecated.  

Prints the rule to a string in a fashion readable by readRuleFromString. The default form simply calls toString() -- you should just override toString() if you don't need the EvolutionState.

readRuleFromString

public void readRuleFromString(java.lang.String string,
                               EvolutionState state)
Reads a rule from a string, which may contain a final '\n'. Override this method. The default form does nothing.

printRule

public void printRule(EvolutionState state,
                      int log,
                      int verbosity)
Prints the rule in a way that can be read by readRule(). The default form simply calls printRuleToString(state). Override this rule to do custom writing to the log, or just override printRuleToString(...), which is probably easier to do.

printRule

public void printRule(EvolutionState state,
                      java.io.PrintWriter writer)
Prints the rule in a way that can be read by readRule(). The default form simply calls printRuleToString(state). Override this rule to do custom writing, or just override printRuleToString(...), which is probably easier to do.

readRule

public void readRule(EvolutionState state,
                     java.io.LineNumberReader reader)
              throws java.io.IOException,
                     java.lang.CloneNotSupportedException
Reads a rule printed by printRule(...). The default form simply reads a line into a string, and then calls readRuleFromString() on that line. Override this rule to do custom reading, or just override readRuleFromString(...), which is probably easier to do.

defaultBase

public Parameter defaultBase()
Description copied from interface: Prototype
Returns the default base for this prototype. This should generally be implemented by building off of the static base() method on the DefaultsForm object for the prototype's package. This should be callable during setup(...).
Specified by:
defaultBase in interface Prototype

protoClone

public java.lang.Object protoClone()
                            throws java.lang.CloneNotSupportedException
Description copied from interface: Prototype
Creates a new individual cloned from a prototype, and suitable to begin use in its own evolutionary context.

The question here is whether or not this means to perform a "deep" or "light" ("shallow") clone, or something in-between. You may need to deep-clone parts of your object rather than simply copying their references, depending on the situation:

Implementations.

If you know that your superclasses will never change their protoClone() implementations, you might try inlining them in your overridden protoClone() method. But this is dangerous (though it yields a small net increase).

In general, you want to keep your deep cloning to an absolute minimum, so that you don't have to call protoClone() but one time.

The approach taken here is the fastest that I am aware of while still permitting objects to be specified at runtime from a parameter file. It would be faster to use the "new" operator; but that would require hard-coding that we can't do. Although using java.lang.Object.clone() entails an extra layer that deals with stripping away the "protected" keyword and also wrapping the exception handling (which is a BIG hit, about three times as slow as using "new"), it's still MUCH faster than using java.lang.Class.newInstance(), and also much faster than rolling our own Clone() method.

Specified by:
protoClone in interface Prototype

protoCloneSimple

public final java.lang.Object protoCloneSimple()
Description copied from interface: Prototype
This should be implemented in a the top-level Prototype ONLY; in fact, it should probably be declared final. It should be implemented as follows:

public final Object protoCloneSimple()
{
try { return protoClone(); }
catch (CloneNotSupportedException e) 
{ throw new InternalError(); } // never happens
} 
Specified by:
protoCloneSimple in interface Prototype

setup

public void setup(EvolutionState state,
                  Parameter base)
Description copied from interface: Prototype
Sets up the object by reading it from the parameters stored in state, built off of the parameter base base. If an ancestor implements this method, be sure to call super.setup(state,base); before you do anything else.

For prototypes, setup(...) is typically called once for the prototype instance; cloned instances do not receive the setup(...) call. setup(...) may be called more than once; the only guarantee is that it will get called at least once on an instance or some "parent" object from which it was ultimately cloned.

Specified by:
setup in interface Prototype