We will use the same project Ch02_Dependency_Injection with the help of the following steps:

1. Add a parameterized constructor to Car, which has the following code:

public Car(String chassis_number, String color, 
 double average, long price, String fuel_type) { 
  // TODO Auto-generated constructor stub 
  this.chassis_number = chassis_number; 
  this.average = average; 
  this.price = price; 
  this.color=color; 
  this.fuel_type=fuel_type; 
} 

2. Add one more bean in the beans.xml file but, this time, instead of using the <property> tag, we will use <constructor-arg> to use the constructor DI. The code will look like this:

<bean id="car_const" class="com.ch02.beans.Car"> 
  <constructor-arg value="eng023"></constructor-arg> 
  <constructor-arg value="green"></constructor-arg> 
  <constructor-arg value="12"></constructor-arg> 
  <constructor-arg value="678900"></constructor-arg> 
  <constructor-arg value="petrol"></constructor-arg> 
</bean> 

3. Create a TestCarConstructorDI class in the default package, which will take the Car object from the container. The code will be as follows:

public static void main(String[] args) { 
  // TODO Auto-generated method stub 
  ApplicationContext context=new 
    ClassPathXmlApplicationContext("beans.xml"); 
  Car car=(Car)context.getBean("car_const"); 
  car.show(); 
} 

4. Execute the code, and the bean values will be displayed on the console.

Here, the container is happy to have each parameter of the constructor with a distinguished data type. However, this is not the same case every time. Many times, occurrence of multiple constructors leads to confusion while setting up the properties. Let's see how.