java async task

.map

jshell> var t1 = CompletableFuture.completedFuture(100)
t1 ==> java.util.concurrent.CompletableFuture@25f38edc[Completed normally]

jshell> var t2 = t1.thenApply(x -> x * 2)
t2 ==> java.util.concurrent.CompletableFuture@1a86f2f1[Completed normally]

jshell> t2.get()
$14 ==> 200

.fmap

jshell> var t1 = CompletableFuture.completedFuture(100)
t1 ==> java.util.concurrent.CompletableFuture@506c589e[Completed normally]

jshell> var t2 = CompletableFuture.completedFuture(200)
t2 ==> java.util.concurrent.CompletableFuture@69d0a921[Completed normally]

jshell> var result = t1.thenCompose($ -> t2)
result ==> java.util.concurrent.CompletableFuture@7aec35a[Completed normally]

jshell> result.get()
$19 ==> 200

javascript equivalent

> var t1 = Promise.resolve(100)
undefined
> var t2 = t1.then(x => x * 2)
undefined
> t2
Promise {
  200,
  domain: 
   Domain {
     domain: null,
     _events: { error: [Function: debugDomainError] },
     _eventsCount: 1,
     _maxListeners: undefined,
     members: [] } }

color theme for javascript and HTML programming

I was using solarised dark for java/scala programming for last couple of years. But since last year sept, I'm more addicted to solarised light with increased font size (15).

I like to try new themes if they work well for my eyes. And recently for javascript/html programming I started using emacs color theme which is very cool. Looks similar to solarized light, but I can see all the keywords unlike in some themes where js keywords like console.log are too pink can't even recognize.


javascript/ typescript

html

color theme IngweLAND is pretty cool too.

com.google.gwt.core.client.JavaScriptException: (TypeError): Object [object Window] has no method 'removeAttribute'

I got following error in my gwt project. The error sounds cool.


10:29:17.381 [ERROR] [projectname] Uncaught exception escaped
com.google.gwt.core.client.JavaScriptException: (TypeError): Object [object Window] has no method 'removeAttribute'
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:248)
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeVoid(ModuleSpace.java:289)
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeVoid(JavaScriptHost.java:107)
    at com.google.gwt.dom.client.Element$.removeAttribute$(Element.java)
    at com.google.gwt.user.cellview.client.AbstractHasData.setFocusable(AbstractHasData.java:887)
    at com.google.gwt.user.cellview.client.AbstractCellTable.setKeyboardSelected(AbstractCellTable.java:1366)
    at com.google.gwt.user.cellview.client.AbstractHasData$View.setKeyboardSelected(AbstractHasData.java:125)
    at com.google.gwt.user.cellview.client.HasDataPresenter.resolvePendingState(HasDataPresenter.java:1417)
    at com.google.gwt.user.cellview.client.HasDataPresenter.access$3(HasDataPresenter.java:1130)
    at com.google.gwt.user.cellview.client.HasDataPresenter$2.execute(HasDataPresenter.java:1055)
    at com.google.gwt.core.client.impl.SchedulerImpl$Task$.executeScheduled$(SchedulerImpl.java:50)
    at com.google.gwt.core.client.impl.SchedulerImpl.runScheduledTasks(SchedulerImpl.java:228)
    at com.google.gwt.core.client.impl.SchedulerImpl.flushFinallyCommands(SchedulerImpl.java:327)
    at com.google.gwt.core.client.impl.Impl.exit(Impl.java:237)
    at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:228)
    at sun.reflect.GeneratedMethodAccessor34.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:601)
    at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
    at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
    at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172)
    at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:292)
    at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:546)
    at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:363)
    at java.lang.Thread.run(Thread.java:722)


As posted at Issue 7348: http://code.google.com/p/google-web-toolkit/issues/detail?id=7348 which mentions Without ui:field attribute, everything is fine.

SOLUTION

Here is what JavaScript removeAttribute does http://www.w3schools.com/jsref/met_element_removeattribute.asp