Package jetbrains.mps.smodel

Class ModelAccess

java.lang.Object

jetbrains.mps.smodel.AbstractModelAccess

jetbrains.mps.smodel.ModelAccess

All Implemented Interfaces:

ModelCommandExecutor, ModelAccess

public abstract class ModelAccess
extends AbstractModelAccess
implements ModelCommandExecutor, ModelAccess

This if front-end for legacy code that deals with a single instance of MA (available through MA.instance()). There are 2 implementations generally available, DefaultModelAccess and WorkbenchModelAccess. Neither is an openapi.ModelAccess available from SRepository#getModelAccess() call, opeanpi.MA instances from repository now merely delegate to the singleton available from #instance() method. For now, WMA provides implementation of methods that deal with Project (i.e. undo support), therefore we keep methods with Project as part of this class implementation API. Instead, we shall implement execute* methods in respective openapi.MA implementations bound to project repositories and remove Project-aware methods from this class altogether. We may want to keep this class for another release as DMA and WMA have different perspective on platform locking (latter adds IDEA platform locks), and with that, we may still delegate general read/write actions of repository's MA to this singleton. The actual implementation of ModelAccess interface methods Probably it is better to merge it with ProjectModelAccess and ModelAccessBase which currently simply delegate all methods to this class

See Also:

ModelAccess

Field Summary

Fields

Modifier and Type	Field	Description
protected static org.apache.log4j.Logger	LOG
protected static ModelAccess	ourInstance

Fields inherited from class jetbrains.mps.smodel.AbstractModelAccess

myCommandActionDispatcher, myReadActionDispatcher, myWriteActionDispatcher

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ModelAccess()

Method Summary

Modifier and Type	Method	Description
protected void	assertNotWriteFromRead()
boolean	canRead()	Indicates, whether the current thread holds the read lock
boolean	canWrite()	Indicates, whether the current thread holds the write lock
abstract void	executeCommand(Runnable r)	Represents a write action executed with respect to platform undo mechanism.
void	executeCommandInEDT(Runnable r)	Represents a write action executed with respect to platform undo mechanism, runs asynchronously from EDT thread.
void	executeUndoTransparentCommand(Runnable r)	FIXME need thorough documentation Executed code has model write, is treated as a command, the only difference is that changes from the transparent action merged with the that of the previous undoable command
protected Lock	getReadLock()
protected Lock	getWriteLock()
boolean	hasScheduledWrites()
static ModelAccess	instance()	Deprecated.
boolean	isCommandAction()
boolean	isInsideCommand()
protected void	onCommandFinished()
protected void	onCommandStarted()
<T> T	runReadAction(Computable<T> c)
<T> T	runWriteAction(Computable<T> c)
boolean	setReadEnabledFlag(boolean flag)	Deprecated.
<T> T	tryRead(Computable<T> c)	Returns the result of the computation, null if locking was unsuccessful.

Methods inherited from class jetbrains.mps.smodel.AbstractModelAccess

addCommandListener, addReadActionListener, addWriteActionListener, checkReadAccess, checkWriteAccess, removeCommandListener, removeReadActionListener, removeWriteActionListener

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.jetbrains.mps.openapi.module.ModelAccess

addCommandListener, addReadActionListener, addWriteActionListener, checkReadAccess, checkWriteAccess, removeCommandListener, removeReadActionListener, removeWriteActionListener, runReadAction, runReadInEDT, runWriteAction, runWriteInEDT

Methods inherited from interface jetbrains.mps.smodel.ModelCommandExecutor

checkReadAccess, checkWriteAccess, flushEventQueue, runReadAction, runReadInEDT, runWriteAction, runWriteInEDT, tryRead

Field Detail

LOG

protected static final org.apache.log4j.Logger LOG

ourInstance

protected static ModelAccess ourInstance

Constructor Detail

ModelAccess

protected ModelAccess()

Method Detail

instance

@Deprecated
public static ModelAccess instance()

Deprecated.

It is better to use SRepository.getModelAccess() method to get the repository access.

Since:

3.1

getReadLock

protected Lock getReadLock()

getWriteLock

protected Lock getWriteLock()

runReadAction

public final <T> T runReadAction(Computable<T> c)

Specified by:

runReadAction in interface ModelCommandExecutor

runWriteAction

public final <T> T runWriteAction(Computable<T> c)

Specified by:

runWriteAction in interface ModelCommandExecutor

tryRead

public final <T> T tryRead(Computable<T> c)

Description copied from interface: ModelCommandExecutor

Returns the result of the computation, null if locking was unsuccessful.

Specified by:

tryRead in interface ModelCommandExecutor

Returns:

assertNotWriteFromRead

protected final void assertNotWriteFromRead()

hasScheduledWrites

public boolean hasScheduledWrites()

canRead

public boolean canRead()

Description copied from interface: ModelAccess

Indicates, whether the current thread holds the read lock

Specified by:

canRead in interface ModelAccess

Specified by:

canRead in interface ModelCommandExecutor

canWrite

public boolean canWrite()

Description copied from interface: ModelAccess

Indicates, whether the current thread holds the write lock

Specified by:

canWrite in interface ModelAccess

Specified by:

canWrite in interface ModelCommandExecutor

isInsideCommand

public final boolean isInsideCommand()

Specified by:

isInsideCommand in interface ModelCommandExecutor

executeCommand

public abstract void executeCommand(Runnable r)

Description copied from interface: ModelAccess

Represents a write action executed with respect to platform undo mechanism. This method shall be invoked from EDT thread only. Unlike ModelAccess.executeCommandInEDT(Runnable), this method executes synchronously

Specified by:

executeCommand in interface ModelAccess

executeCommandInEDT

public final void executeCommandInEDT(Runnable r)

Description copied from interface: ModelAccess

Represents a write action executed with respect to platform undo mechanism, runs asynchronously from EDT thread. This method may be invoked from any thread.

Specified by:

executeCommandInEDT in interface ModelAccess

executeUndoTransparentCommand

public final void executeUndoTransparentCommand(Runnable r)

Description copied from interface: ModelAccess

FIXME need thorough documentation Executed code has model write, is treated as a command, the only difference is that changes from the transparent action merged with the that of the previous undoable command

Specified by:

executeUndoTransparentCommand in interface ModelAccess

isCommandAction

public boolean isCommandAction()

Specified by:

isCommandAction in interface ModelAccess

Returns:

true if there's a command (either with ModelAccess.executeCommand(Runnable) or ModelAccess.executeCommandInEDT(Runnable)) being executed

onCommandStarted

protected void onCommandStarted()

Overrides:

onCommandStarted in class AbstractModelAccess

onCommandFinished

protected void onCommandFinished()

Overrides:

onCommandFinished in class AbstractModelAccess

setReadEnabledFlag

@Deprecated
public boolean setReadEnabledFlag(boolean flag)

Deprecated.

Description copied from interface: ModelCommandExecutor

Enables canRead() without actually acquiring the read lock (screw you, ReadWriteLock!). Requires read lock in the "parent" thread. Thread local. Returns previous value, to which it must be reset after use (in finally{}).

Specified by:

setReadEnabledFlag in interface ModelCommandExecutor

Returns:

previous value