jsf - Binding attribute causes duplicate component ID found in the view -

-

here jsf code: 

<h:inputtext binding="#{bean.input}" />

and here part of backing bean binding support:

private htmlinputtext input;  public void setinput(htmlinputtext input) {     this.input = input; }  public htmlinputtext getinput() {     return this.input; }

when open page @ first time works fine when open @ second time (refresh or open same url in tab or other way) duplicate id error. error message says <h:inputtext> has no unique id. here part of long error message:

java.lang.illegalargumentexception: component id formid:inputid has been found in view     +id: inputid type: javax.faces.component.html.htmlinputtext@cafebabe

the problem occured after added binding attribute. if remove it, work fine again. how use binding attribute?

duplicate component id errors may occur when:

  • same id used on different components inside same namingcontainer.
  • physically different components bound same property of same bean.
  • the <f:subview> been declared in include page instead of parent page.
  • the same include page included multiple times inside same namingcontainer.
  • a component been dynamically created without having explicit id assigned.

here, namingcontainer among others <h:form>, <h:datatable> , <f:subview>.

when using binding, should bind property used exclusively component in question on per-request basis. specific case indicates binding been shared multiple components, perhaps across different requests. when bind component property of backing bean, backing bean should absolutely not in broader scope request scope. see jsf 2.0 specitication chapter 3.1.5 (emphasis mine):

3.1.5 component bindings

...

component bindings used in conjunction javabeans dynamically instantiated via managed bean creation facility (see section 5.8.1 “variableresolver , default variableresolver”). it recommend application developers place managed beans pointed @ component binding expressions in “request” scope. because placing in session or application scope require thread-safety, since uicomponent instances depends on running inside of single thread. there potentially negative impacts on memory management when placing component binding in “session” scope.

see also:


Comments

Post a Comment

Popular posts from this blog

c++ - Convert big endian to little endian when reading from a binary file -

-
this question has answer here: how convert between big-endian , little-endian values in c++? 28 answers i've been looking around how convert big-endian little-endians. didn't find solve problem. seem there's many way can conversion. anyway following code works ok in big-endian system. how should write conversion function work on little-endian system well? this homework, since systems @ school running big-endian system. it's got curious , wanted make work on home computer also #include <iostream> #include <fstream> using namespace std; int main() { ifstream file; file.open("file.bin", ios::in | ios::binary); if(!file) cerr << "not able read" << endl; else { cout << "opened" << endl; int i_var; double d_var; while(!file.eof()) {...
Read more

C#: Application without a window or taskbar item (background app) that can still use Console.WriteLine() -

-
i'm trying create application adheres following: no taskbar no console or form window can utilize console.writeline() . (i.e. if executes app command prompt write console.) the problem if create windows form (or wpf) application can have there no taskbar, console or window show up, console.writeline() nothing. if create console app, writes console, can't figure out how hide (and if did hide it, write command prompt window?)... how do this? just create standard console application. callers responsibility hide window caused program (from how run c# console application console hidden ): system.diagnostics.processstartinfo start = new system.diagnostics.processstartinfo(); start.filename = dir + @"\myprocesstostart.exe"; start.windowstyle = system.diagnostics.processwindowstyle.hidden;
Read more

unicode - Are email addresses allowed to contain non-alphanumeric characters? -

-
i'm building website using `django. website have significant users non-english speaking countries. i want know if there technical restrictions on types of characters email address contain. are email addresses allowed contain english alphabets, numbers, "_", "@" , "."? are allowed contain non-english alphabets "é" or "ü"? are allowed contain chinese or japanese or other unicode characters? email address consists of 2 parts local before @ , domain goes after. rules these parts different: for local part can use ascii: latin letters - z - z digits 0 - 9 special characters !#$%&'*+-/=?^_`{|}~ dot ., not first or last, , not in sequence space , "(),:;<>@[] characters allowed restrictions (they allowed inside quoted string, backslash or double-quote must preceded backslash) plus since 2012 can use international characters above u+007f , encoded as utf-8 . domain part more res...
Read more