Spring Autowiring "constructor"

constructor autowiring in spring

For the System requirements, project required jars and project creation setup steps please refer the below links:-

http://www.javatechtipssharedbygaurav.com/2013/06/spring-beans-autowiring.html

Example of "constructor" autowiring mode:-

ShoeCompanyDetails.java

package com.spring.gaurav.autowire.constructor.example;

public class ShoeCompanyDetails {

            private String shoeCompanyName;

            private String companyType;

            private String companyHeadquarters;

            private int companyFoundationyear;

            public String getShoeCompanyName() {

                        return shoeCompanyName;

            }

            public void setShoeCompanyName(String shoeCompanyName) {

                        this.shoeCompanyName = shoeCompanyName;

            }

            public String getCompanyType() {

                        return companyType;

            }

            public void setCompanyType(String companyType) {

                        this.companyType = companyType;

            }

            public String getCompanyHeadquarters() {

                        return companyHeadquarters;

            }

            public void setCompanyHeadquarters(String companyHeadquarters) {

                        this.companyHeadquarters = companyHeadquarters;

            }

            public int getCompanyFoundationyear() {

                        return companyFoundationyear;

            }

            public void setCompanyFoundationyear(int companyFoundationyear) {

                        this.companyFoundationyear = companyFoundationyear;

            }

}

Shoemaker.java

package com.spring.gaurav.autowire.constructor.example;

import com.spring.gaurav.autowire.constructor.example.ShoeCompanyDetails;

public class Shoemaker {

            private String companyFounder;

            private ShoeCompanyDetails shoeCompanyDetails;

            public void displayShoemakerCompanyHistory() {

                        System.out.println("SHOE COMPANY NAME :- "

                                                + shoeCompanyDetails.getShoeCompanyName()

                                                + ", \nCOMPANYFOUNDER NAME :- " + companyFounder + ",");

                        System.out.println("COMPANY TYPE :- "

                                                + shoeCompanyDetails.getCompanyType()

                                                + ", \nCOMPANY HEADQUARTERS :- "

                                                + shoeCompanyDetails.getCompanyHeadquarters()

                                                + " \nAND COMPANY FOUNDATION YEAR :- "

                                                + shoeCompanyDetails.getCompanyFoundationyear());

            }

            public Shoemaker(ShoeCompanyDetails shoeCompanyDetails) {

                        this.shoeCompanyDetails = shoeCompanyDetails;

            }

            public String getCompanyFounder() {

                        return companyFounder;

            }

            public void setCompanyFounder(String companyFounder) {

                        this.companyFounder = companyFounder;

            }

}

autowire-mode-constructor-beans.xml

<beans xmlns="http://www.springframework.org/schema/beans"

            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

            xsi:schemaLocation="http://www.springframework.org/schema/beans

    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

  <bean id="shoemakerBean" class="com.spring.gaurav.autowire.constructor.example.Shoemaker" autowire="constructor">

        <property name="companyFounder" value="KARL TOOSBUY" />

  </bean>

 

  <bean id="shoeCompanyDetailsId" class="com.spring.gaurav.autowire.constructor.example.ShoeCompanyDetails">

        <property name="shoeCompanyName" value="ECCO" />

        <property name="companyType" value="AKTIESELSKAB(BOTH PUBLICLY TRADED AND PRIVATE)" />

        <property name="companyHeadquarters" value="BREDEBRO, DENMARK" />

        <property name="companyFoundationyear" value="1963"></property>

  </bean>

</beans>

ConstructorAutowireClient.java

package com.spring.gaurav.autowire.constructor.example;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

public class ConstructorAutowireClient {

            public static void main(String args[]) {

                        ApplicationContext appContext = new ClassPathXmlApplicationContext(

                                                "autowire-mode-constructor-beans.xml");

                        Shoemaker shoemaker = (Shoemaker) appContext.getBean("shoemakerBean");

                        shoemaker.displayShoemakerCompanyHistory();

            }

}

/**

 * Notes: According to "autowire-mode-constructor-beans.xml" bean file, we called

 * shoemakerBean in this client program, In the xml bean configuration file, we

 * have declared autowire = constructor, so according to the constructor

 * autowire mode first container will try to find the bean with class attribute

 * ShoeCompanyDetails, as we have declared private ShoeCompanyDetails

 * shoeCompanyDetails in Shoemaker.java file, and using the ShoeCompanyDetails

 * class as an argument of Shoemaker class constructor then it injects

 * ShoeCompanyDetails bean class properties which is shoeCompanyName,

 * companyType, companyHeadquarters and companyFoundationyear and injects value

 * of companyFounder property of Shoemaker class. It works similarly as byType

 * autowire mode.

 *

 */

Result:-

log4j:WARN No appenders could be found for logger (org.springframework.context.support.ClassPathXmlApplicationContext).

log4j:WARN Please initialize the log4j system properly.

SHOE COMPANY NAME :- ECCO,

COMPANYFOUNDER NAME :- KARL TOOSBUY,

COMPANY TYPE :- AKTIESELSKAB(BOTH PUBLICLY TRADED AND PRIVATE),

COMPANY HEADQUARTERS :- BREDEBRO, DENMARK

AND COMPANY FOUNDATION YEAR :- 1963

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