使用Maven插件提取使用Spring注入的参数

Question

I have an application which uses Spring to wire up some beans in various combinations. Below are simplified classes which help to illustrate the the relevant part of the application.

class A {
   private List<B> fieldB;

    public void setFieldB(List<B> fieldB) { this.fieldB = fieldB; }
    public List<B> getFieldB() { return this.fieldB; }
}

class B {
    private String name;
    private String field1;
    private String field2;

    public void setName(String name) { this.name = name; }
    public void setField1(String value1) { this.field1 = value1; }
    public void setField2(String value2) { this.field2 = value2; }

    public String getName() { return this.name; }
    public String getField1() { return this.field1; }
    public String getField2() { return this.field2; }
}

spring-context-file1.xml

<?xml ...>
<beans ...>
    <bean id="a" class="com.example.A">
        <property name="fieldB">
           <list> <ref bean="b1"/> <ref bean="b2"/> </list>
        </property>
    </bean>

    <bean id="b1" class="com.example.B">
        <property name="name">
           <value>b1</value>
        </property>
        <property name="field1">
           <value>fieldOneValueOne</value>
        </property>
        <property name="field2">
           <value>fieldOneValueTwo</value>
        </property>
    <bean>

    <bean id="b2" class="com.example.B">
        <property name="name">
           <value>b2</value>
        </property>
        <property name="field1">
           <value>fieldTwoValueOne</value>
        </property>
        <property name="field2">
           <value>fieldTwoValueTwo</value>
        </property>
    <bean>
</beans>

Given the above what I would like to do is have the following information extracted at build time:

spring-context-file1.cfg  
b1 => {fieldOneValueOne, fieldOneValueTwo}  
b2 => {fieldTwoValueOne, fieldTwoValueTwo} 

I have opted to develop a Maven plugin to do this requisite processing. Basically the plugin will load up the Spring context file and use the getBean("...") method to get the beans of interest. I have however run into a problem. In order to extract the information from the beans the plugin code needs to know what type of object it's manipulating. This means the plugin code will need to be compiled against the main project code. This seems wrong to me. Does any know of any means for a Maven plugin to extract this sort of information?

Answer 1

I think instead of extracting the information from the Spring config file, you should create a common file that the Spring context can load bean properties from. Then you can parse this file quite easily at build time (hopefully without writing a custom Maven plugin - this will complicate your build horribly). Have a look at the new property management in Spring 3.1: http://blog.springsource.com/2011/02/15/spring-3-1-m1-unified-property-management/