Created a SafeInterval that requeues itself on the client invoker thread

(the main client thread, which will generally be the AWT thread unless the
client is being used in a situation where there is no AWT) to avoid bad
thread clashy.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@1424 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/presents/client/util/SafeInterval.java

@@ -0,0 +1,55 @@
+//
+// $Id: SafeInterval.java,v 1.1 2002/06/05 02:50:57 mdb Exp $
+
+package com.threerings.presents.client.util;
+
+import com.samskivert.util.Interval;
+import com.samskivert.util.IntervalManager;
+
+import com.threerings.presents.client.Client;
+
+/**
+ * Used in conjunction with the {@link Client}, this class provides a
+ * means by which code can be run on the client main thread at some point
+ * in the future, either as a recurring interval or as a one shot deal.
+ * The code is built on top of the {@link IntervalManager} services.
+ *
+ * <p> A {@link SafeInterval} instance should be created and then
+ * scheduled to run using the {@link IntervalManager}. For example:
+ *
+ * <pre>
+ *     IntervalManager.register(new SafeInterval(_ctx.getClient()) {
+ *         public void run () {
+ *             System.out.println("Foo!");
+ *         }
+ *      }, 25L * 1000L, null, false);
+ * </pre>
+ */
+public abstract class SafeInterval
+    implements Runnable, Interval
+{
+    /**
+     * Creates a safe interval instance that will queue itself up for
+     * execution using the supplied client when it expires.
+     */
+    public SafeInterval (Client client)
+    {
+        _client = client;
+    }
+
+    /**
+     * Called (on the client main thread) when the interval period has
+     * expired. If this is a recurring interval, this method will be
+     * called each time the interval expires.
+     */
+    public abstract void run ();
+
+    /** Handles the proper scheduling and queueing. */
+    public void intervalExpired (int id, Object arg)
+    {
+        _client.getInvoker().invokeLater(this);
+    }
+
+    /** The client via which we queue ourselves when we expire. */
+    protected Client _client;
+}