Important This project has moved to delight-utils
Note: This project has been superseded by the project concurrency-api.
Develop shared codebases for JRE and GWT Apps. Core feature of this library: Abstract Concurrency API.
Please note:
- Check the blog post 'Threads in GWT?' for more infos about this library.
- Please subscribe to my blog for updates.
- This library has been developed as part of the onedb project.
Usage examples in the following for Executors, Timers and Collections.
The oneUtils concurrency API allows to define Java Executor-style executors in GWT and/or JRE apps.
final Concurrency con = OneUtilsJre.newJreConcurrency();
// ^-- replace with 'new GwtConcurrency()' for GWT environments
// see https://gist.github.com/2791639
// -----
// Immediate Executor
// -----
// Immediate executors will execute the instructions immediately in the
// calling thread.
final OneExecutor immEx = con.newExecutor().newImmideateExecutor();
immEx.execute(new Runnable() {
@Override
public void run() {
System.out.println("Did immideately.");
}
});
// all executors must be shutdown to free resources in JRE environments
immEx.shutdown(new WhenExecutorShutDown() {
@Override
public void thenDo() {
}
@Override
public void onFailure(final Throwable t) {
}
});
// -----
// Single Thread Executor
// -----
// Single thread executors require the specification of an 'owner'
// object.
// This object can help in debugging by pointing to the place where
// the executor was created.
final OneExecutor singEx = con.newExecutor().newSingleThreadExecutor(
new Object() {
});
singEx.execute(new Runnable() {
@Override
public void run() {
System.out.println("Executed in different thread.");
}
});
// -----
// Multi-Thread Executor
// -----
// Multi-Thread Executors are backed by a Single Thread Executor in a
// GWT environment. In an JRE environment, they are backed by a
// Thread Pool.
final OneExecutor multEx = con.newExecutor().newParallelExecutor(3,
new Object() {
});
multEx.execute(new Runnable() {
@Override
public void run() {
System.out
.println("Potentially executed in parallel with other executions.");
}
});The oneUtils concurrency API provides an abstract API for the creation of Timers in GWT and JRE environments.
final Concurrency con = OneUtilsJre.newJreConcurrency();
// ^-- replace with 'new GwtConcurrency()' for GWT environments
// see https://gist.github.com/2791639
// -----
// Timer for one invocation
// -----
con.newTimer().scheduleOnce(200, new Runnable() {
@Override
public void run() {
System.out.println("Do in 200 ms");
}
});
// -----
// Timer for multiple invocations
// -----
con.newTimer().scheduleRepeating(200, 100, new Runnable() {
@Override
public void run() {
System.out.println("Do in 200 ms and then every 100 ms.");
}
});
// -----
// Timer with minimal delay
// -----
con.runLater(new Runnable() {
@Override
public void run() {
System.out.println("Do in background thread.");
}
});The API further allows for an abstract way to create thread-safe collections (using Collections.synchroizedList etc. won't
compile in a GWT app).
final Concurrency con = OneUtilsJre.newJreConcurrency();
// ^-- replace with 'new GwtConcurrency()' for GWT environments
// see https://gist.github.com/2791639
// -----
// Thread Safe List
// -----
// If any of the collections is instantiated in a GWT environment, they
// are created as default (non-synchronized) collections, since in
// GWT it is assured that there is no concurrent access to the
// collections
final List<String> threadSafeList = con.newCollection()
.newThreadSafeList(String.class);
threadSafeList.add("item1");
// -----
// Thread Safe Map
// -----
final Map<Integer, String> threadSafeMap = con.newCollection()
.newThreadSafeMap(Integer.class, String.class);
threadSafeMap.put(25, "text");
// -----
// Thread Safe Queue
// -----
final Queue<Integer> threadSafeQueue = con.newCollection()
.newThreadSafeQueue(Integer.class);
threadSafeQueue.add(25);
// -----
// Thread Safe Set
// -----
final Set<String> threadSafeSet = con.newCollection().newThreadSafeSet(
String.class);
threadSafeSet.add("element1");