Spring Framework - Dependency Injection by setter method with Example
Injecting primitive and string-based values
We can inject the dependency by setter method also. The <property> subelement of <bean> is used for setter injection. Here we are going to inject
- primitive and String-based values
- Dependent object (contained object)
- Collection values etc.
Injecting primitive and string-based values by setter method
Let's see the simple example to inject primitive and string-based values by setter method. We have created three files here:
Employee.java
applicationContext.xml
Test.java
Employee.java
It is a simple class containing three fields id, name and city with its setters and getters and a method to display these informations.
package com.springexample;
public class Employee {
private int id;
private String name;
private String city;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
void display(){
System.out.println(id+" "+name+" "+city);
}
}
applicationContext.xml
We are providing the information into the bean by this file. The property element invokes the setter method. The value subelement of property will assign the specified value.
<?xml version="1.0" encoding="UTF-8"?>
<beans
xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">
<bean id="obj" class="com.springexample.Employee">
<property name="id">
<value>20</value>
</property>
<property name="name">
<value>Arun</value>
</property>
<property name="city">
<value>ghaziabad</value>
</property>
</bean>
</beans>
Test.java
This class gets the bean from the applicationContext.xml file and calls the display method.
package com.springexample;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.core.io.*;
public class Test {
public static void main(String[] args) {
Resource r=new ClassPathResource("applicationContext.xml");
BeanFactory factory=new XmlBeanFactory(r);
Employee e=(Employee)factory.getBean("obj");
s.display();
}
}
Output:20 Arun Ghaziabad.
wow... great post.. thanks adim
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