java - What does it mean to "proxy a bean"? -



java - What does it mean to "proxy a bean"? -

at work , online maintain hearing term "proxy" respect enterprise java development. example, metrics-spring uses phrase:

this module next things:

creates metrics , proxies beans contain methods annotated @timed, @metered, @exceptionmetered, , @counted [emphasis mine]

i'm unfamiliar lot of language in java ecosystem of frameworks , libraries. sense have understanding of what bean is, i'm still not clear how 1 proxy bean.

what mean proxy bean?

typically, have bean like

bean bean = new bean(); // created context

with this, can bean class declares behavior (invoke methods).

there times nice if could, example, track how long method invocation takes.

you do

long start = .. // start time bean.invoke(); long end = .. // end time // end - start

but doing each method invocation sucks. so, instead, patterns, architectures, , styles aspect oriented programming exist.

instead of bean above, you'd have

bean bean = new timingbean(new bean()); // 1 time again done context

where timingbean proxy type extends , implements types bean extends , implements. intents , purposes is bean, adds bunch of additional behavior before delegating each invocation bean object. in case, track how long each of bean's method's took execute.

basic spring uses jdk proxies , cglib proxies. here differences between them.

it uses scheduling , asynchronous invocations. uses transactional back upwards databases. uses caching. uses java based container configuration.

java spring proxy

Comments

Post a Comment

Popular posts from this blog

Delphi change the assembly code of a running process -

Delphi change the assembly code of a running process - i'm trying alter address 00741fa5 has push test.009e721c . alter push test.009e71c8 . procedure callback; asm force $9e71c8 end; procedure tform2.btn1click(sender: tobject); var ppid :dword; pprocess : cardinal; begin getwindowthreadprocessid(findwindow(nil,pchar('test')), @ppid); pprocess := openprocess(process_all_access, false, ppid); injectasm(pprocess, $741fa5, 10, integer(@callback), 0); end; here injectasm function (with error checking) function injectasm(process: longword; injectaddress, injectsize, codeaddress, codesize : integer): pointer; var csize, rsize : integer; replaced : array of byte; jmp : array [0..4] of byte; jmpaddress : integer; nopv : byte; : integer; nbr: ulong_ptr; begin //injectsize must equal or greater 5, because need space our //(far) jmp wwxxyyzz instruction //if there's no space, inject in place of few instructions if injectsize ...
Read more

json - Hibernate and Jackson (java.lang.IllegalStateException: Cannot call sendError() after the response has been committed) -

json - Hibernate and Jackson (java.lang.IllegalStateException: Cannot call sendError() after the response has been committed) - hello have problem hibernate , jackson. have 2 pojos @entity @table(name = "users") public class user implements serializable { static final long serialversionuid = 4235637833262722256l; @id @generatedvalue private int id; @column(name = "creation_date") private date creationdate; @column(name = "first_name") private string firstname; @column(name = "last_name") private string lastname; @version @column(name = "version") private int version; @column(name = "e_mail") private string email; @column(name = "enabled") private boolean enabled; @column(name = "login") private string login; @column(name = "password") private string password; @jsonmanagedreference("role") @onetomany(mappedby = "user", cascade = cascadetype.all,fetch = fetchtyp...
Read more

C++ 11 "class" keyword -

C++ 11 "class" keyword - i've started using c++ 11 little bit more , have few questions on special uses of class keyword. know it's used declare class, there's 2 instances have seen don't understand: method<class t>(); and class class_name *var; why precede typename keyword class in first example, , keyword pointer in sec example? that known elaborated type specifier , necessary when class name "shadowed" or "hidden" , need explicit. class t { }; // love of god don't t t; t t2; if compiler smart, give these warnings: main.cpp:15:5: error: must utilize 'class' tag refer type 't' in scope t t2; ^ class main.cpp:14:7: note: class 't' hidden non-type declaration of 't' here t t; ^ if class not defined, deed forwards declaration. for example: template <typename t> void method() { using type = typename t::value_type; } method...
Read more