java - Can we create an Array of Generic class? -

-

संभव डुप्लिकेट:

मैं 10 तत्वों वाले स्टैक बनाना चाहता हूं, मैं जेनेरिक के साथ ऐसा करने की कोशिश कर रहा हूं मैं टाइप टी की एक स्टैक क्लास बनाकर शुरू किया, लेकिन जब मैं सामान्य प्रकार की सरणी को इन्स्तांत करने की कोशिश करता हूं तो मुझे संकलन त्रुटि मिलती है। 

  सार्वजनिक वर्ग स्टैक & lt; T & gt; {निजी टी [] Stk = नया टी [10]; }   
 क्या मैं यहाँ गलत कर रहा हूं?   
 
 
 आप ऐसा नहीं कर सकते कोड के बारे में कुछ गुप्त गोलियों का उपयोग किए बिना, और फिर भी आपको एक  असुरक्षित  कलाकार को अंत में करना होगा जो पहली जगह में सुरक्षित होने का प्रयास करने के पूरी तरह से पूरे कारण को नष्ट कर देता है।  
 इसका कारण यह है कि जावा में  type erasure  नामक कुछ है, कम्पाइलर सभी जेनेरिक सूचनाओं को फेंकता है और रनटाइम को पता नहीं है कि  T  क्या है  
 ऐसा करने का सबसे पसंदीदा तरीका यह है:  
  @SuppressWarnings ("अनचेक") स्थिर & lt; T & gt; टी [] नए अर्रे (कक्षा & lt; T & gt; प्रकार, पूर्णांक लंबाई) {वापसी (टी []) java.lang.reflect.Array.newInstance (प्रकार, लंबाई); }   
 यह सूची आवृत्ति के बारे में एक कोड  toArray ()  पर  सूची & lt; T & gt; > कार्यान्वयन हैक।  
 इस पर अधिक चर्चा के लिए  
 देखें।

Comments

Post a Comment

Popular posts from this blog

php - Creating canonical URLs with custom route-classes -

-
I am trying to implement the canonical url and to combine with custom route classes. URL-SACAME is something like this: / category-x / article / 123 / category-y / article / 123 I am creating a custom route - the expansion of the class Zend_Controller_Router_Route_Regex and checks that the article is 123 and the correct category-name is included in the URL. If the article is in 123 square-X and the user is reaching square-y, then I want to redirect to the correct URL. But there is no clear possibility to do this directly to the roads. What is the best practice approach here? I often do this in my action controller like something ... // Get / Category-Y / Article / 123 $ $ article- & gt; URL is generated, and it contains / category-x / article / 123 if (this-> --request-> getRequestUri ()! = $ Article-> URL) {return $ this- & gt; ; _helper-> Redirector-> GoToUrl ($ paragraph-> url); } In this example, $ article-> The url will need ...
Read more

mysql - BLOB/TEXT column 'value' used in key specification without a key length -

-
I have developed an extension which works up to 1.6 on Magren (I'm trying Enterprise Edition, And I think the community is the same problem, because it is the same code). In my install script, I see the $ installer-> gt; CreateEntityTables ($ this- & gt; getTable ('alphanum / info')); The installation is done until it is not in the _text unit table. It crashed there! It turns out that when I log in to SQL and run it via PHPmyadmin, then this error is: Blob / Text column 'value' is used without the key 'key' . I saw the code there, and this is what is trying to create an index on the value column: -> addIndex ($ this- & gt; getIdxName ($ eavTableName, array ( 'attribute_id array (' attribute_id ',' value ')) - & gt; addIndex ($ this- & gt; getIdxName ($ eavTableName, array (' entity_type_id ' , 'Value')), array ('entity_type_id', 'value')) If there is no if statement is n...
Read more

mysql - php global within a class but outside a function? -

-
I can do $ conn from within my function such as: function Xyz ($ A) {global $ conn; ....} I am thinking that this is a way of doing a class before. class abc {global $ conn; Public function xyz ($ a) {$ conn- & gt; Execute ...} public function xya ($ a) {$ conn- & gt; Execute ...}} The above method gives me an error I know that I can get it this way: class ABC {Public Function xyz ($ a) {global $ conn; $ Conn- & gt; Execute ...} Public Function xya ($ a) {global $ conn; $ Conn- & gt; Execute ...}} I hope you can understand what I mean. Thanks in advance for the help. Your second example is possible, your first is not. There is no such thing as a member of a class variable that is a global variable, or the use of scope like yours is your first example. Generally, however, I would advise to avoid global use. Keyword I absolutely do a lot of PHP programming and have never used it in serious (actually, nothing in the last 10 or so years). . If you ...
Read more