Java try-finally return design question -

-

in java, try { ... } { ... } executed unintuitively me. illustrated in question, does execute in java?, if have return statement in try block, ignored if block defined. example, function

boolean test () {     try {         return true;     }     {         return false;     } }

will return false. question: why this? there particular philosophy behind design decision made java? appreciate insight, thank you.

edit: i'm particularly interested 'why' java thinks it's ok violate semantics define. if 'return' in try block, method should return right , there. jvm decides ignore instruction , return subroutine hasn't yet been reached.

technically speaking, return in try block won't ignored if finally block defined, if block includes return.

it's dubious design decision probably mistake in retrospect (much references being nullable/mutable default, and, according some, checked exceptions). in many ways behaviour consistent colloquial understanding of finally means - "no matter happens beforehand in try block, run code." hence if return true finally block, overall effect must to return true, no?

in general, seldom idiom, , should use finally blocks liberally cleaning up/closing resources if ever return value them.


Comments

Post a Comment

Popular posts from this blog

android - Spacing between the stars of a rating bar? -

-
ho can set spacing beween stars? thats ratingbar: ratingbar = (ratingbar) inflater.inflate(r.layout.ratingbar, null); ratingbar.setlayoutparams(new layoutparams(layoutparams.wrap_content, layoutparams.wrap_content)); the layout: <?xml version="1.0" encoding="utf-8"?> <ratingbar xmlns:android="http://schemas.android.com/apk/res/android" style="@style/mystyle" android:layout_alignparentright="true" android:layout_height="19dp" android:layout_width="wrap_content" android:numstars="5"> </ratingbar> the style: <style name="mystyle" parent="@android:style/widget.ratingbar"> <item name="android:progressdrawable">@drawable/android_r2_ratingstar_yellow</item> <item name="android:indeterminatedrawable">@drawable/android_r2_ratingstar_grey</item> </style> thanks, cheers you have ...
Read more

html - Instapaper-like algorithm -

-
does of algorithm extracts contents webpage? instapaper ? there 2 steps instapaper does: find main content block on page (excluding headers, footers, menus etc) from content block extract , format text to find content block (typically html block element, div containing key page text content) instapaper uses algorithm 1 used readability . can @ source of readability.js see what's going on, @ core tries find area on page highest text/link ratio, although has other simple scoring metrics (e.g. off top of head, things ratio of text commas, para elements etc) go heuristics. once have identified root node element, relevant content, you'll need format it, if want can pull node element containing text out of source document , insert yours, in reality you'll want remove existing styles , apply own, standard , feel. if want output nice text-only can use jericho's renderer . update1 : should mention else instapaper - follow 'pagination' links (...
Read more

c# - How to execute a particular part of code asynchronously in a class -

-
i creating speech recognition engine that's going respond user commands.i have created button enable , disable speech recognition per user convenience.i have used dispose() of speech engine disable speech recoginition.here code private void button1_click(object sender, routedeventargs e) { engineon = !engineon; if (engineon) { speechengine = speech.createspeechengine(); //speech class creates , returns new speech engine. speechengine.audiolevelupdated += new eventhandler<audiolevelupdatedeventargs>(speechengine_audiolevelupdated); // use system's default microphone speechengine.setinputtodefaultaudiodevice(); speechengine.loadgrammar(new dictationgrammar()); // start listening speechengine.recognizeasync(recognizemode.multiple); } else { speechclass.myengine.dispose(); } } but disposal of speech obj...
Read more