toolbus.process
Class Merge

java.lang.Object
  toolbus.process.ProcessExpression
      toolbus.process.Merge

All Implemented Interfaces:

StateElement

public class Merge
extends ProcessExpression
implements StateElement

Author:

paulk, Aug 7, 2002 Merge implements the parallell composition operator || It maintains its two arguments and randomly selects in which argument the next atom will be executed. When both arguments are exhausted, execution continues with the followSet of the merge.

Field Summary

private ProcessExpression[]	expr
private State[]	initialState
private int	LEFT
private boolean	leftLast
private State	mergeState
private ProcessInstance	processInstance
private static java.util.Random	rand
private int	RIGHT
private State[]	state

Fields inherited from class toolbus.process.ProcessExpression

posInfo, tbfactory

Constructor Summary

Merge(ProcessExpression left, ProcessExpression right, TBTermFactory tbfactory, PositionInformation posInfo)

Method Summary

void	activate() Activate the StateElement, i.e.
protected void	compile(ProcessInstance processInstance, java.util.Stack<java.lang.String> calls, State follows)
protected void	computeFirst()
boolean	contains(StateElement a) Check whether a StateElement contains another StateElement.
protected ProcessExpression	copy()
ProcessInstance[]	debugExecute() Executes the state element in debug mode.
boolean	execute() Execute this StateElement
AtomList	getAtoms()
State	getFirst()
ProcessInstance	getProcess()
java.util.List<aterm.ATerm>	getTests() Returns a collection containing all tests that are associated with this state element.
State	gotoNextStateAndActivate()
State	gotoNextStateAndActivate(StateElement se) Get the successor of the StateElement for a given other StateElement elem.
private void	initState()
boolean	isEnabled() Is this StateElelement enabled for execution, i.e., are its associated tests all true? If enabled, the StateElement is ready for execution.
static boolean	nextBoolean() Generate next random boolean.
protected void	replaceFormals(Environment env)
void	setTest(aterm.ATerm test, Environment env) Add a test to this state element.
java.lang.String	toString()

Methods inherited from class toolbus.process.ProcessExpression

addToFirst, addToFollow, getFollow, getPosInfo, setFirst, setFollow

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface toolbus.StateElement

getFollow, getPosInfo

Field Detail

rand

private static final java.util.Random rand

LEFT

private final int LEFT

See Also:

Constant Field Values

RIGHT

private final int RIGHT

See Also:

Constant Field Values

processInstance

private ProcessInstance processInstance

expr

private final ProcessExpression[] expr

state

private final State[] state

initialState

private final State[] initialState

mergeState

private final State mergeState

leftLast

private boolean leftLast

Constructor Detail

Merge

public Merge(ProcessExpression left,
             ProcessExpression right,
             TBTermFactory tbfactory,
             PositionInformation posInfo)

Method Detail

computeFirst

protected void computeFirst()

Specified by:

computeFirst in class ProcessExpression

compile

protected void compile(ProcessInstance processInstance,
                       java.util.Stack<java.lang.String> calls,
                       State follows)
                throws ToolBusException

Specified by:

compile in class ProcessExpression

Throws:

ToolBusException

replaceFormals

protected void replaceFormals(Environment env)
                       throws ToolBusException

Specified by:

replaceFormals in class ProcessExpression

Throws:

ToolBusException

copy

protected ProcessExpression copy()

Specified by:

copy in class ProcessExpression

getAtoms

public AtomList getAtoms()

Specified by:

getAtoms in class ProcessExpression

getFirst

public State getFirst()

Overrides:

getFirst in class ProcessExpression

contains

public boolean contains(StateElement a)

Description copied from interface: StateElement

Check whether a StateElement contains another StateElement. In the simplest case of Atom this is just an identity test. In composite cases (e.g. Merge), it requires a recursive search.

Specified by:

contains in interface StateElement

Parameters:

a - the StateElement

Returns:

true (contained in) or false (not contained in)

getProcess

public ProcessInstance getProcess()

Specified by:

getProcess in interface StateElement

Returns:

the ProcessInstance to which the StateElement belongs

setTest

public void setTest(aterm.ATerm test,
                    Environment env)
             throws ToolBusException

Description copied from interface: StateElement

Add a test to this state element. Tests implement conditionals but not delays / timeouts.

Specified by:

setTest in interface StateElement

env - to be used for executing the test

Throws:

ToolBusException

getTests

public java.util.List<aterm.ATerm> getTests()

Description copied from interface: StateElement

Returns a collection containing all tests that are associated with this state element.

Specified by:

getTests in interface StateElement

Returns:

A collection containing all tests that are associated with this state element.

isEnabled

public boolean isEnabled()

Description copied from interface: StateElement

Is this StateElelement enabled for execution, i.e., are its associated tests all true? If enabled, the StateElement is ready for execution.

Specified by:

isEnabled in interface StateElement

Returns:

true (enabled) or false (not enabled).

initState

private void initState()

gotoNextStateAndActivate

public State gotoNextStateAndActivate()

Specified by:

gotoNextStateAndActivate in interface StateElement

Returns:

the successor State of the StateElement

gotoNextStateAndActivate

public State gotoNextStateAndActivate(StateElement se)

Description copied from interface: StateElement

Get the successor of the StateElement for a given other StateElement elem. This typically used for a composite StateElement to get a specific successor. TODO: Probably this method should be combined with the previous one.

Specified by:

gotoNextStateAndActivate in interface StateElement

Returns:

the successor State of the StateElement

activate

public void activate()

Description copied from interface: StateElement

Activate the StateElement, i.e. make it ready for execution. This may involve initialization and the setting of timers.

Specified by:

activate in interface StateElement

nextBoolean

public static boolean nextBoolean()

Generate next random boolean.

execute

public boolean execute()
                throws ToolBusException

Description copied from interface: StateElement

Execute this StateElement

Specified by:

execute in interface StateElement

Returns:

true if execution was completed.

Throws:

ToolBusException

debugExecute

public ProcessInstance[] debugExecute()
                               throws ToolBusException

Description copied from interface: StateElement

Executes the state element in debug mode.

Specified by:

debugExecute in interface StateElement

Returns:

The collection of partners that cooperated with the execution of the state element. Null if the execution did not complete.

Throws:

ToolBusException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object