X-Git-Url: https://gerrit.onap.org/r/gitweb?a=blobdiff_plain;f=datarouter-node%2Fsrc%2Fmain%2Fjava%2Forg%2Fonap%2Fdmaap%2Fdatarouter%2Fnode%2FTaskList.java;h=a77277f29f354cc49e0cc963fc8d2af58f915c07;hb=6c78b3e6a0a67c73f931337356a172cc69cee0e8;hp=33e4f801a965377b005ef97b147f066a8e8ba5ca;hpb=8cbe8a88bc6dfe8673a33a017fe6a5a3e7ce86c3;p=dmaap%2Fdatarouter.git
diff --git a/datarouter-node/src/main/java/org/onap/dmaap/datarouter/node/TaskList.java b/datarouter-node/src/main/java/org/onap/dmaap/datarouter/node/TaskList.java
index 33e4f801..a77277f2 100644
--- a/datarouter-node/src/main/java/org/onap/dmaap/datarouter/node/TaskList.java
+++ b/datarouter-node/src/main/java/org/onap/dmaap/datarouter/node/TaskList.java
@@ -24,63 +24,54 @@
package org.onap.dmaap.datarouter.node;
-import java.util.*;
+import java.util.HashSet;
+import java.util.Iterator;
/**
- * Manage a list of tasks to be executed when an event occurs.
- * This makes the following guarantees:
+ * Manage a list of tasks to be executed when an event occurs. This makes the following guarantees:
*
* - Tasks can be safely added and removed in the middle of a run.
* - No task will be returned more than once during a run.
* - No task will be returned when it is not, at that moment, in the list of tasks.
* - At the moment when next() returns null, all tasks on the list have been returned during the run.
- * - Initially and once next() returns null during a run, next() will continue to return null until startRun() is called.
+ *
- Initially and once next() returns null during a run, next() will continue to return null until startRun() is
+ * called.
*
*/
-public class TaskList {
+class TaskList {
+
private Iterator runlist;
- private HashSet tasks = new HashSet();
+ private HashSet tasks = new HashSet<>();
private HashSet togo;
private HashSet sofar;
private HashSet added;
private HashSet removed;
- /**
- * Construct a new TaskList
- */
- public TaskList() {
- }
-
/**
* Start executing the sequence of tasks.
*/
- public synchronized void startRun() {
- sofar = new HashSet();
- added = new HashSet();
- removed = new HashSet();
- togo = new HashSet(tasks);
+ synchronized void startRun() {
+ sofar = new HashSet<>();
+ added = new HashSet<>();
+ removed = new HashSet<>();
+ togo = new HashSet<>(tasks);
runlist = togo.iterator();
}
/**
- * Get the next task to execute
+ * Get the next task to execute.
*/
- public synchronized Runnable next() {
+ synchronized Runnable next() {
while (runlist != null) {
if (runlist.hasNext()) {
Runnable task = runlist.next();
- if (removed.contains(task)) {
- continue;
+ if (addTaskToSoFar(task)) {
+ return task;
}
- if (sofar.contains(task)) {
- continue;
- }
- sofar.add(task);
- return (task);
}
- if (added.size() != 0) {
+ if (!added.isEmpty()) {
togo = added;
- added = new HashSet();
+ added = new HashSet<>();
removed.clear();
runlist = togo.iterator();
continue;
@@ -97,7 +88,7 @@ public class TaskList {
/**
* Add a task to the list of tasks to run whenever the event occurs.
*/
- public synchronized void addTask(Runnable task) {
+ synchronized void addTask(Runnable task) {
if (runlist != null) {
added.add(task);
removed.remove(task);
@@ -108,11 +99,22 @@ public class TaskList {
/**
* Remove a task from the list of tasks to run whenever the event occurs.
*/
- public synchronized void removeTask(Runnable task) {
+ synchronized void removeTask(Runnable task) {
if (runlist != null) {
removed.add(task);
added.remove(task);
}
tasks.remove(task);
}
+
+ private boolean addTaskToSoFar(Runnable task) {
+ if (removed.contains(task)) {
+ return false;
+ }
+ if (sofar.contains(task)) {
+ return false;
+ }
+ sofar.add(task);
+ return true;
+ }
}