How to create bean by double reference?

Question

I do not know how to articulate/search the issue in the first place.

So the bean initialized are :

<bean id='domain' factory-bean='appConfig' factory-method='getDomain'/
<bean id='prod' class='java.lang.String'> <constructor-arg value='Base.Prod'/> </bean>
<bean id='test' class='java.lang.String'> <constructor-arg value='Base.Beta' /> </bean>

Now I need to create a bean "X" using the value of Prod or Test depending on the value of domain. If domain is Prod,use the bean of Prod to initialize bean X else use Test.

${${domain}} does not work. I tried searching but was not able to find a question that meant this.

Maybe this helps: https://stackoverflow.com/a/3486315/6239524 — kalsowerus, Jul 04 '17 at 08:42
@Enigmagirl, put it in code formatter block, not in blockquote. — M. Prokhorov, Jul 04 '17 at 09:28
You dont need to create 2 different bean. You can with one bean and create 2 properties file.if you have more properties to change — soorapadman, Jul 04 '17 at 09:33
@kalsowerus, I agree that creating xmls based on environment is much better to maintain xmls but at this point, there is only one bean and I feel it is too much work for it. — Enigma girl, Jul 04 '17 at 09:33
@soorapadman, explanation with example will help. Unable to understand how it will solve my problem — Enigma girl, Jul 04 '17 at 09:38
@soorapadman, even with newer version it would not matter I believe because there is no concept which can be used to initialize that bean . To answer your question, project has latest support to Spring 4 but it contains xmls which are written previously. — Enigma girl, Jul 04 '17 at 09:44
@Enigmagirl i'm sure you can do with beans ` ` use same bean id for both — soorapadman, Jul 04 '17 at 09:47

score 1 · Answer 1 · answered Jul 04 '17 at 08:54

1

This will work

@Value("${domain}")
private String domain;

Combined with

-Ddomain=dev

Spring adds any system properties to properties read from properties file.

answered Jul 04 '17 at 08:54

Essex Boy

7,565
2
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24

I am using older version of Spring. So they are XML based – Enigma girl Jul 04 '17 at 09:07
1

@Enigmagirl the Value annotation is the same, it's unaffected by XML or Java config. – Essex Boy Jul 04 '17 at 10:01

score 1 · Answer 2 · answered Jul 04 '17 at 09:17

1

@EssexBoy's answer in XML would look something like this:

<bean id="domain" class="java-lang.String">
    <constructor-arg>
        <value>${domain}</value>
    </construcotr-arg>
</bean>

answered Jul 04 '17 at 09:17

kalsowerus

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${domain} will give the value of the domain bean. But what I want is , get the value of the bean whose name is the value stored in domain bean. Domain = prod /test So based on domain value, I would want to refer to prod bean or test bean – Enigma girl Jul 04 '17 at 09:30
@Enigmagirl Your prod/test beans are both Strings, why won't one String with either value work? – kalsowerus Jul 04 '17 at 09:31
Either of them will work. When I get the value of domain as Prod, I want Base.Prod to be assigned for Bean X, when domain value is test then I want Base.Beta to be assigned for Bean X. It is conditional and I do not know how conditional is handled when using xmls – Enigma girl Jul 04 '17 at 09:36
@Enigmagirl including different XMLs for each environment might be the only option if you can't use the value of `${domain}` directly... – kalsowerus Jul 04 '17 at 09:39
Alas! I wonder how conditional beans were handled before. Like if something is null, then initialize a bean with abc value, else initialize xyz value. – Enigma girl Jul 04 '17 at 09:45

score 0 · Accepted Answer · answered Jul 05 '17 at 09:48

0

Finally found the answer. There is a way to refer the test/prod bean through domain. You just got to use #{domain}. More information here: spEL

Use it as :

<bean id="ThatBean" class="whicheverClass">   
 <constructor-arg ref="#{domain}" /> 
</bean>

answered Jul 05 '17 at 09:48

Enigma girl

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How to create bean by double reference?

3 Answers3