tcl.lang
Class WrappedCommand

java.lang.Object
  tcl.lang.WrappedCommand

public class WrappedCommand
extends Object

A Wrapped Command is like the Command struct defined in the C version in the file generic/tclInt.h. It is "wrapped" around a TclJava Command interface reference. We need to wrap Command references so that we can keep track of sticky issues like what namespace the command is defined in without requiring that every implementation of a Command interface provide method to do this. This class also handles command and execution traces. This class is only used in the internal implementation of Jacl.

Field Summary

Command	cmd The actual command interface that is being wrapped
int	cmdEpoch incremented to invalidate any references.
boolean	deleted Means that the command is in the process of being deleted.
String	hashKey A string that stores the name of the command.
Namespace	ns The namespace where the command is located
HashMap<String,WrappedCommand>	table Reference to the table that this command is defined inside.

Constructor Summary

WrappedCommand()

Method Summary

boolean	hasCommandTraces()
void	invoke(Interp interp, TclObject[] objv) Call cmd.cmdProc after calling execution traces on this command, and call execution traces after this command exits.
boolean	mustCallInvoke(Interp interp)
void	removeAllCommandTraces() Eliminate all the command traces on thsi command
String	toString()
void	traceCommand(CommandTrace trace) Set a command trace on this command
TclObject	traceCommandInfo(Interp interp) Get a list of all command traces on this command
void	traceExecution(ExecutionTrace trace) Set an execution trace on this command
TclObject	traceExecutionInfo(Interp interp) Get a list of all execution traces on this command
void	untraceCommand(int type, String callbackCmd) Remove a command trace on this command
void	untraceExecution(int type, String callbackCmd) Remove an execution trace on this command

Methods inherited from class java.lang.Object

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

Field Detail

table

public HashMap<String,WrappedCommand> table

Reference to the table that this command is defined inside. The hashKey member can be used to lookup this WrappedCommand instance in the table of WrappedCommands. The table member combined with the hashKey member are are equivilent to the C version's Command->hPtr.

hashKey

public String hashKey

A string that stores the name of the command. This name is NOT fully qualified.

ns

public Namespace ns

The namespace where the command is located

cmd

public Command cmd

The actual command interface that is being wrapped

deleted

public boolean deleted

Means that the command is in the process of being deleted. Other attempts to delete the command should be ignored.

cmdEpoch

public int cmdEpoch

incremented to invalidate any references. that point to this command when it is renamed, deleted, hidden, or exposed. This field always have a value in the range 1 to Integer.MAX_VALUE (inclusive). User code should NEVER modify this value.

Constructor Detail

WrappedCommand

public WrappedCommand()

Method Detail

hasCommandTraces

public boolean hasCommandTraces()

Returns:

true if there are any command traces on this command

removeAllCommandTraces

public void removeAllCommandTraces()

Eliminate all the command traces on thsi command

untraceCommand

public void untraceCommand(int type,
                           String callbackCmd)
                    throws TclException

Remove a command trace on this command

Parameters:

type - CommandTrace.RENAME or CommandTrace.DELETE

callbackCmd - callback command to remove

Throws:

TclException

traceCommand

public void traceCommand(CommandTrace trace)
                  throws TclException

Set a command trace on this command

Parameters:

trace - trace to add to command

Throws:

TclException

traceCommandInfo

public TclObject traceCommandInfo(Interp interp)
                           throws TclException

Get a list of all command traces on this command

Parameters:

interp - interpreter for error messages

Returns:

List, in the form of [trace command info]

Throws:

TclException

traceExecution

public void traceExecution(ExecutionTrace trace)
                    throws TclException

Set an execution trace on this command

Parameters:

trace - trace to add to command

Throws:

TclException

untraceExecution

public void untraceExecution(int type,
                             String callbackCmd)
                      throws TclException

Remove an execution trace on this command

Parameters:

type - ExecutionTrace.ENTER, ExecutionTrace.LEAVE, ExecutionTrace.ENTERSTEP or ExecutionTrace.LEAVESTEP

callbackCmd - callback command to remove

Throws:

TclException

traceExecutionInfo

public TclObject traceExecutionInfo(Interp interp)
                             throws TclException

Get a list of all execution traces on this command

Parameters:

interp - interpreter for error messages

Returns:

List, in the form of [trace execution info]

Throws:

TclException

mustCallInvoke

public final boolean mustCallInvoke(Interp interp)

Returns:

true if the caller must call WrappedCommand.invoke(Interp, TclObject[]) because there are execution traces in effect. Note that it is always OK to call invoke() instead of cmd.cmdProc(), but doing so adds an extra Java stack frame that may limit how deep Tcl code stack frames can go.

invoke

public void invoke(Interp interp,
                   TclObject[] objv)
            throws TclException

Call cmd.cmdProc after calling execution traces on this command, and call execution traces after this command exits. Application code should use this call, rather than directly calling Command.cmdProc(Interp, TclObject[]) which does not fire execution traces.

Parameters:

interp - The interpreter containing the context for thie command, and where results are returned

objv - argument list for command; objv[0] is the command name itself

Throws:

TclException - on any errors

toString

public String toString()

Overrides:

toString in class Object