Spring Tutorial - Spring Set Properties








We can fill value or a list of values to a Java bean defined in Spring xml configuration file.

The following sections show how to fill data to Set.

Java Bean

In order to show how to use xml configuration file to fill collection properties, we defined a Customer object with four collection properties.

package com.java2s.common;

import java.util.HashSet;
import java.util.Set;

public class Customer {
  private Set<Object> sets = new HashSet<Object>();

  public Set<Object> getSets() {
    return sets;
  }

  public void setSets(Set<Object> sets) {
    this.sets = sets;
  }

  public String toString() {
    return sets.toString();
  }
}

Person Java Bean

package com.java2s.common;

public class Person {
  private String name;
  private int age;
  private String address;

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public int getAge() {
    return age;
  }

  public void setAge(int age) {
    this.age = age;
  }

  public String getAddress() {
    return address;
  }

  public void setAddress(String address) {
    this.address = address;
  }

  @Override
  public String toString() {
    return "Person [name=" + name + ", age=" + age + ", address=" + address
        + "]";
  }
  
}




Set

The following code shows how to fill data to a java.util.Set typed property.

The code fills in three values. The first one is hard-coded value 1. The second one is a bean reference. We have to define PersonBean somewhere in order to use it here. The third one is a bean definition with property-setting.

...
<property name="sets">
    <set>
      <value>1</value>
      <ref bean="PersonBean" />
      <bean class="com.java2s.common.Person">
        <property name="name" value="java2sSet" />
        <property name="address" value="address" />
        <property name="age" value="28" />
      </bean>
    </set>
</property>
...




Example

Full Spring's 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="CustomerBean" class="com.java2s.common.Customer">
    <!-- java.util.Set -->
    <property name="sets">
      <set>
        <value>1</value>
        <ref bean="PersonBean" />
        <bean class="com.java2s.common.Person">
          <property name="name" value="java2sSet" />
          <property name="address" value="address" />
          <property name="age" value="28" />
        </bean>
      </set>
    </property>
  </bean>
  <bean id="PersonBean" class="com.java2s.common.Person">
    <property name="name" value="java2s1" />
    <property name="address" value="address 1" />
    <property name="age" value="28" />
  </bean>
</beans>

Here is the code to load and run the configuration.

package com.java2s.common;

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("CustomerBean");
      System.out.println(cust);
    }
}

Output

Customer [
sets=[
1, 
Person [address=address 1, age=28, name=java2s1], 
Person [address=address, age=28, name=java2sSet]]
]


Download Java2s_Spring_Set_Properties.zip

SetFactoryBean

SetFactoryBean class can create a concrete Set collection HashSet or TreeSet in Spring's bean configuration file.

The following code shows how to use SetFactoryBean.

Here is the Java bean class.

package com.java2s.common;
//from  w w  w.  j av  a  2  s.  co  m
import java.util.HashSet;
import java.util.Set;

public class Customer {
  private Set<Object> sets = new HashSet<Object>();

  public Set<Object> getSets() {
    return sets;
  }

  public void setSets(Set<Object> sets) {
    this.sets = sets;
  }

  public String toString() {
    return sets.toString();
  }
}

Here is the Spring's 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="CustomerBean" class="com.java2s.common.Customer">
    <property name="sets">
      <bean class="org.springframework.beans.factory.config.SetFactoryBean">
        <property name="targetSetClass">
          <value>java.util.HashSet</value>
        </property>
        <property name="sourceSet">
          <list>
            <value>1</value>
            <value>2</value>
            <value>3</value>
          </list>
        </property>
      </bean>
    </property>
  </bean>
</beans>


Download Java2s_Spring_SetFactoryBean.zip

util schema

We also can use util schema and <util:set> to fill data to java.util.Set.

<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
  xmlns:util="http://www.springframework.org/schema/util"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
  http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
  http://www.springframework.org/schema/util
  http://www.springframework.org/schema/util/spring-util-2.5.xsd">
  <bean id="CustomerBean" class="com.java2s.common.Customer">
    <property name="sets">
      <util:set set-class="java.util.HashSet">
        <value>1</value>
        <value>2</value>
        <value>3</value>
      </util:set>
    </property>
  </bean>
</beans>


Download Java2s_Spring_set_util.zip

Use the following code to run the application.

package com.java2s.common;
 
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("CustomerBean");
      System.out.println(cust);
 
    }
}

The code above generates the following result.