Class LayoutRunner

java.lang.Object
java.lang.Thread
org.graphstream.ui.layout.LayoutRunner
All Implemented Interfaces:
Runnable

public class LayoutRunner
extends Thread
Allows to run a layout in a distinct thread.

A layout runner will run in its own thread and periodically activate a layout algorithm on a graph event stream (you do not need a graph). This implementation is mainly used by the graph viewer but could be used by any program that needs a layout algorithm that run continuously on a dynamic graph (adapting the layout as the graph changes).

The layout algorithms in GraphStream are iterative versions that can be called repeatedly to take graph dynamics into account and may produce a result only after several invocations. This is why the layout runner invokes the layout on a regular basis. The runner is temporized, it will not run in a loop as fast as possible, instead it will wait a little between each layout invocation. When the last layout invocation indicated the layout was good, it will wait longer that when the last invocation indicated the layout was not good (stabilized). These two times can be configured using setNaps(long, long).

Once you finished using the runner, you must call release() to break the link with the event source and stop the thread. The runner cannot be used after.

  • Constructor Details

    • LayoutRunner

      public LayoutRunner​(Source source, Layout layout)
      New layout runner that listens at the given source and compute a layout on its graph structure in a distinct thread.
      Parameters:
      source - The source of graph events.
      layout - The layout algorithm to use.
    • LayoutRunner

      public LayoutRunner​(Source source, Layout layout, boolean start)
      New layout runner that listen at the given source and compute a layout on its graph structure in a distinct thread.
      Parameters:
      source - The source of graph events.
      layout - The layout algorithm to use.
      start - Start the layout thread immediately ? Else the start() method must be called later.
    • LayoutRunner

      public LayoutRunner​(Graph graph, Layout layout, boolean start, boolean replay)
      New layout runner that listen at the given graph and compute a layout on its graph structure in a distinct thread. A pipe is still created to listen at the graph. This means that the graph is never directly used.
      Parameters:
      graph - The source of graph events.
      layout - The layout algorithm to use.
      start - Start the layout thread immediately ? Else the start() method must be called later.
      replay - If the graph already contains some data, replay events to create the data, this is mostly always needed.
  • Method Details

    • newLayoutPipe

      public ProxyPipe newLayoutPipe()
      Pipe out whose input is connected to the layout algorithm. You can safely connect as a sink to it to receive events of the layout from a distinct thread.
    • run

      public void run()
      Specified by:
      run in interface Runnable
      Overrides:
      run in class Thread
    • release

      public void release()
      Release any link to the source of events and stop the layout proces. The thread will end after this method has been called.
    • setNaps

      public void setNaps​(long longNap, long shortNap)
      Configure the time to wait between each layout invocation. The long nap configures the time to wait when the last layout invocation indicated the layout was stabilized, the short nap is used in the other case.
      Parameters:
      longNap - The time to wait between stabilized layout invocations, by default 80.
      shortNap - The time to wait between non stabilized layout invocations, by default 10.