NumberFormatException when injecting int property

Question

This is my class :

ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
PropertyPlaceholderConfigurer pph = new PropertyPlaceholderConfigurer();
pph.setLocations(new Resource[]{new ClassPathResource("one.properties"), new ClassPathResource("two.properties")});
context.addBeanFactoryPostProcessor(pph);
context.refresh();

Controller obj1 = (Controller) context.getBean("controller");
System.out.println(obj1.getMessage());

Controller2 obj2 = (Controller2) context.getBean("controller2");
System.out.println(obj2.getMessage());
System.out.println(obj2.getInteger());

This is the relevant xml configuration:

   <bean id="controller" class="com.sample.controller.Controller">
       <property name="message" value="${ONE_MESSAGE}"/>
   </bean>
   <bean id="controller2" class="com.sample.controller.Controller2">
       <property name="message" value="${TWO_MESSAGE}"/>
        <property name="integer" value="${TWO_INTEGER}"/>
   </bean>

one.properties:

ONE_MESSAGE=ONE

two.properties:

TWO_MESSAGE=TWO
TWO_INTEGER=30

TWO_MESSAGE is assigned correctly as String TWO. I am getting NumberFormatException when injecting a TWO_INTEGER. Is there a way to achieve this without adding a setter that takes String and coverts it to int in Controller2 class?

The error :

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'controller2' defined in class path resource [beans.xml]: Initialization of bean failed; nested exception is org.springframework.beans.TypeMismatchException: Failed to convert property value of type 'java.lang.String' to required type 'int' for property 'integer'; nested exception is java.lang.NumberFormatException: For input string: "${TWO_INTEGER}"

Thanks.

The `PropertyPlaceholderConfigurer` is obviously not finding the properties files or the properties files do not contain any property like `${TWO_INTEGER}`. Have you check this? — LaurentG, Aug 02 '13 at 19:27
I checked this. In fact, other String properties from the same file are getting assigned correctly. one.properties has : `ONE_MESSAGE=ONE` and two.properties has : `TWO_MESSAGE=TWO TWO_INTEGER=30` and 'TWO_MESSAGE' property is read correctly. Just, to clarify. there are two lines in two.properties not the way its formatted here to show one line.Thanks. — sharma sharma, Aug 02 '13 at 19:34
You could edit your question and add this relevant information. It will be better formatted as in a comment. — LaurentG, Aug 02 '13 at 19:40
Why you can't define PropertyPlaceholderConfigurer in xml file? — Luca Basso Ricci, Aug 02 '13 at 19:43
LaurentG : edited the question. @bellabax : The properties file names are decided at run time. Unless there is a way to define it in xml file and then change it programatically, I have to do it this way. Thanks. — sharma sharma, Aug 02 '13 at 19:45
you can pass runtime names in command line as system properties with -D option or like [here](http://stackoverflow.com/questions/3965446/how-to-read-system-environment-variable-in-spring-applicationcontext)? — Luca Basso Ricci, Aug 02 '13 at 19:51

score 5 · Accepted Answer · answered Aug 02 '13 at 19:53

Probably your application falling in this line (please provide full stacketrace if i mistake):

ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");

because Spring can't parse ${TWO_INTEGER} (this properties doesn't loaded in context as yet). So you can just move context initializing after properties loaded:

 ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext();
 PropertyPlaceholderConfigurer pph = new PropertyPlaceholderConfigurer();
 pph.setLocations(new Resource[]{new ClassPathResource("one.properties"), new ClassPathResource("two.properties")});
 context.addBeanFactoryPostProcessor(pph);
 context.setConfigLocation("beans.xml");
 context.refresh();

Hope this help.

It works now. Thanks a lot for the solution and the explanation. Really appreciate it. Curious : Why are the String properties read correctly even when they are in the same file? — sharma sharma, Aug 02 '13 at 19:58

NumberFormatException when injecting int property

1 Answers1