Package jebl.util

Class CompositeProgressListener

  • All Implemented Interfaces:
    Cancelable
    public final class CompositeProgressListener
extends ProgressListener
    A ProgressListener that is suitable for a task that consists of several subtasks. You specify the relative duration of each subtask, and then the subtasks' setProgress() calls with values between 0 and 1 are translated to reflect the overall progress on the whole (combined) task. In other words, each subtask reports progress as if it were the whole task, and the CompositeProgressListener translates this into overall progress. This also implies that calling setComplete() or setProgress(1.0) marks the current subtask rather than the entire task completed.

    As the combined progress listener cannot know which subtask it is currently being called from, you have to explicitely let it know when a new subtask (not the first) starts, by calling beginNextSubtask(). Thus when the constructor is passed an array of N doubles as its second argument, beginNextSubtask() should be called precisely N-1 times.

    Alternatively, instead of calling beginNextSubtask() after each subtask (except the last), you can instead call beginSubtask() before each subtask (including the first).

    Version:
    $Id: CompositeProgressListener.java 1068 2010-09-08 23:59:59Z matt_kearse $
    Author:
    Tobias Thierer

    • Constructor Detail

      • CompositeProgressListener

        public CompositeProgressListener​(ProgressListener listener,
                                 double... operationDuration)
        construct a new composite ProgressListener.
        Parameters:
        listener - the ProgressListener that all progress reports are forwarded to after adjusting them for the currently active sub-task
        operationDuration - a list of relative weightings to give each sub task.

      • CompositeProgressListener

        public CompositeProgressListener​(ProgressListener listener,
                                 int numberOfEvenlyWeightedSubTasks)
        Construct a CompositeProgressListener with a number of evenly weighted subtasks.
        Parameters:
        listener - the ProgressListener that all progress reports are forwarded to after adjusting them for the currently active sub-task
        numberOfEvenlyWeightedSubTasks - the number of evenly weighted sub-tasks.

    • Method Detail

      • beginSubtask

        public void beginSubtask()
        Used as an alternative to beginNextSubtask(). Instead of calling beginNextSubtask() once after each subtask (except the last), you can instead call beginSubTask at the beginning of every subtask including the first.

      • beginSubtask

        public void beginSubtask​(java.lang.String message)
        Used as an alternative to beginNextSubtask(). Instead of calling beginNextSubtask() once after each subtask (except the last), you can instead call beginSubTask at the beginning of every subtask including the first.
        Parameters:
        message - a message to be displayed to the user as a prefix in the progress message

      • addProgress

        public boolean addProgress​(double fractionCompletedDiff)
        Increments the progress of the current sub task by this much. Using this method is generally a bad idea. Use ProgressListener.setProgress(double) instead.
        Parameters:
        fractionCompletedDiff - the amount ot increase the current progress by between 0 and 1.
        Returns:
        true if canceled.

      • hasNextSubtask

        public boolean hasNextSubtask()
        Returns:
        true if there is another subtask available after the current one

      • clearAllProgress

        public void clearAllProgress()
        Clear all progress, including that of previous subtasks. Note: if the task has already been canceled, this does not reset its status to non-canceled.

      • beginNextSubtask

        public void beginNextSubtask​(java.lang.String message)
        Convenience method to start the next operation AND set a new message.
        Parameters:
        message - message to set (will be passed to setMessage()

      • beginNextSubtask

        public void beginNextSubtask()
        begins the next subtask. Should not be called on the first subtask, but should only be called to start tasks after the first one. If you wish to call a begin subtask method for each task including the first, use beginSubtask() instead.

      • setComplete

        public final boolean setComplete()

      • getRootProgressListener

        public ProgressListener getRootProgressListener()
        Returns:
        The root ProgressListener that this forwards adjusted progress reports to.

      • addFeedbackAction

        public void addFeedbackAction​(java.lang.String label,
                              java.lang.String description,
                              SimpleListener listener)
        Description copied from class: ProgressListener
        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 case listener will never be fired.
        Overrides:
        addFeedbackAction in class ProgressListener
        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

      • setTitle

        public void setTitle​(java.lang.String title)
        Description copied from class: ProgressListener
        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.
        Overrides:
        setTitle in class ProgressListener
        Parameters:
        title - the title of a progress window (if any). Must not be null.