Spring inject Date into bean property – CustomDateEditor

Spring example to show you how to inject a “Date” into bean property.

package com.tuts.heomi.netmon;

import java.util.Date;

public class Customer {

	Date date;

	public Date getDate() {
		return date;
	}

	public void setDate(Date date) {
		this.date = date;
	}

	@Override
	public String toString() {
		return "Customer [date=" + date + "]";
	}

}

Bean configuration file

<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-2.5.xsd">

	<bean id="customer" class="com.tuts.heomi.netmon.Customer">
		<property name="date" value="2010-01-31" />
	</bean>

</beans>

Run it

package com.tuts.heomi.netmon;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class App {
	public static void main(String[] args) {
		ApplicationContext context = new ClassPathXmlApplicationContext(
				"SpringBeans.xml");

		Customer cust = (Customer) context.getBean("customer");
		System.out.println(cust);
		
	}
}

You will encounter follow error messages :

Caused by: org.springframework.beans.TypeMismatchException: 
	Failed to convert property value of type [java.lang.String] to 
	required type [java.util.Date] for property 'date'; 

nested exception is java.lang.IllegalArgumentException: 
	Cannot convert value of type [java.lang.String] to
	required type [java.util.Date] for property 'date': 
	no matching editors or conversion strategy found

Solution

In Spring, you can inject a Date via two methods :

1. Factory bean

Declare a dateFormat bean, in “customer” bean, reference “dateFormat” bean as a factory bean. The factory method will call SimpleDateFormat.parse() to convert String into Date object automatically.

<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-2.5.xsd">

	<bean id="dateFormat" class="java.text.SimpleDateFormat">
		<constructor-arg value="yyyy-MM-dd" />
	</bean>

	<bean id="customer" class="com.tuts.heomi.netmon.Customer">
		<property name="date">
			<bean factory-bean="dateFormat" factory-method="parse">
				<constructor-arg value="2010-01-31" />
			</bean>
		</property>
	</bean>

</beans>

2. CustomDateEditor

Declares a CustomDateEditor class to convert String into java.util.Date.

	<bean id="dateEditor"
	   class="org.springframework.beans.propertyeditors.CustomDateEditor">
	
		<constructor-arg>
			<bean class="java.text.SimpleDateFormat">
				<constructor-arg value="yyyy-MM-dd" />
			</bean>
		</constructor-arg>
		<constructor-arg value="true" />
	</bean>

And declares another “CustomEditorConfigurer”, to make Spring convert bean properties whose type is java.util.Date.

    <bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
		<property name="customEditors">
			<map>
				<entry key="java.util.Date">
					<ref local="dateEditor" />
				</entry>
			</map>
		</property>
	</bean>

Full example of bean configuration file.

<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-2.5.xsd">

	<bean id="dateEditor"
		class="org.springframework.beans.propertyeditors.CustomDateEditor">

		<constructor-arg>
			<bean class="java.text.SimpleDateFormat">
				<constructor-arg value="yyyy-MM-dd" />
			</bean>
		</constructor-arg>
		<constructor-arg value="true" />

	</bean>

	<bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
		<property name="customEditors">
			<map>
				<entry key="java.util.Date">
					<ref local="dateEditor" />
				</entry>
			</map>
		</property>
	</bean>

	<bean id="customer" class="com.tuts.heomi.netmon.Customer">
		<property name="date" value="2010-02-31" />
	</bean>

</beans>

Download Source Code

$ git clone https://github.com/favtuts/java-spring-tutorials.git
$ cd SpringBeanDate

Reference

1. Spring property editors