Package jebl.util
Class ProgressListener
java.lang.Object
jebl.util.ProgressListener
- All Implemented Interfaces:
Cancelable
- Direct Known Subclasses:
BasicProgressListener
,CompositeProgressListener
,ProgressListener.Wrapper
- Version:
- $Id: ProgressListener.java 1068 2010-09-08 23:59:59Z matt_kearse $ ProgressListener guarantees the following contract: A call to any of the methods setProgress(), setMessage(), isCanceled() and setIndeterminateProgress() at a given time yields the same result as a call to another of these methods would have resulted at the same time. Once the task whose progress we are observing has been canceled, calls to either of these methods reflect this. This does not prevent subclasses from introducing a way to "reset" a ProgressListener that was previously canceled from not being canceled any more. Any object may exhibit undefined behaviour when dealing with a ProgressListener that is not fulfilling this contract.
- Author:
- Matt Kearse
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Nested Class Summary
Nested ClassesModifier and TypeClassDescriptionstatic class
A decorator progress listener which delegates all method calls to an internal progress listener. -
Field Summary
FieldsModifier and TypeFieldDescriptionstatic final ProgressListener
A ProgressListener that ignores all events and always returns false fromisCanceled()
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionvoid
addFeedbackAction
(String label, String description, SimpleListener listener) Adds an action that can choose to provide feedback.void
addFeedbackAction
(String label, SimpleListener listener) Equivalent toaddFeedbackAction(label,"",listener)
abstract boolean
This method must be implemented by all subclasses.void
removeFeedbackAction
(String label) Removes a feedback action previously added usingaddFeedbackAction(String, jebl.util.SimpleListener)
.final boolean
Set an image associated with the current progress.final boolean
Sets indefinite progress (i.e.final boolean
setMessage
(String message) Set visible user message.final boolean
setProgress
(double fractionCompleted) final boolean
setProgress
(int currentStep, int numberOfSteps) Same as callingsetProgress(((double)currentStep)/numberOfSteps)
final boolean
setProgress
(long currentStep, long numberOfSteps) Same as callingsetProgress(((double)currentStep)/numberOfSteps)
void
Sets a title associated with whatever is being done.
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Field Details
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EMPTY
A ProgressListener that ignores all events and always returns false fromisCanceled()
. Useful when you don't care about the progress results or canceling the operation.
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Constructor Details
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ProgressListener
public ProgressListener()
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Method Details
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setProgress
public final boolean setProgress(double fractionCompleted) - Parameters:
fractionCompleted
- a number between 0 and 1 inclusive representing the fraction of the operation completed. If you are unsure of the fraction completed, callsetIndeterminateProgress()
instead.- Returns:
- true if the user has requested that this operation be canceled.
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setProgress
public final boolean setProgress(int currentStep, int numberOfSteps) Same as callingsetProgress(((double)currentStep)/numberOfSteps)
- Parameters:
currentStep
- between 0 and numberOfSteps inclusivenumberOfSteps
- the total number of steps. Must be greater than 0.- Returns:
- true if the user has requested that this operation be canceled.
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setProgress
public final boolean setProgress(long currentStep, long numberOfSteps) Same as callingsetProgress(((double)currentStep)/numberOfSteps)
- Parameters:
currentStep
- between 0 and numberOfSteps inclusivenumberOfSteps
- the total number of steps. Must be greater than 0.- Returns:
- true if the user has requested that this operation be canceled.
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setIndeterminateProgress
public final boolean setIndeterminateProgress()Sets indefinite progress (i.e. "some progress has happened, but I don't know how close we are to finishing").- Returns:
- true if the user has requested that this operation be canceled.
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setMessage
Set visible user message.- Parameters:
message
- a user visible message. If this is null, it will be automatically replaced with an empty string.- Returns:
- true if the user has requested that this operation be canceled.
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setImage
Set an image associated with the current progress. A progress listener may choose to optionally display this image wherever is appropriate.- Parameters:
image
- an image- Returns:
- true if the user has requested that this operation be canceled.
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addFeedbackAction
Equivalent toaddFeedbackAction(label,"",listener)
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addFeedbackAction
Adds an action that can choose to provide feedback. For example, an operation may choose to provide a "Skip to next step" button alongside the cancel button. There is no requirement that a ProgressListener actually present this to the user - it may choose to ignore this method, in which caselistener
will never be fired.- Parameters:
label
- a label describing this feedback action. For example, "Skip to next step"listener
- a listener to be notified when the user chooses to invoke this action
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removeFeedbackAction
Removes a feedback action previously added usingaddFeedbackAction(String, jebl.util.SimpleListener)
.- Parameters:
label
- The label used as a parameter toaddFeedbackAction(String, jebl.util.SimpleListener)
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setTitle
Sets a title associated with whatever is being done. This will not necessarily even be presented to the user, but typically will be presented as the title of a progress window.- Parameters:
title
- the title of a progress window (if any). Must not be null.
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isCanceled
public abstract boolean isCanceled()This method must be implemented by all subclasses. It is called fromsetProgress(double)
,setIndeterminateProgress()
andsetMessage(java.lang.String)
to determine the return value of these methods.- Specified by:
isCanceled
in interfaceCancelable
- Returns:
- true if the user has requested that this operation be canceled.
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