Spring PropertyPlaceholderConfigurer load from DB

Question

Is it possible to load properties from DB with Custom Spring PropertyPlaceholderConfigurer? and is it also possible that datasource provided to custom PropertyPlaceholderCon

Answer 1

Spring Context XML

    
        
        
        
        
            
                classpath:db.properties
            
        
    

 
        ${imosdb.driver}
        ${imosdb.url}
        ${imosdb.username}
        ${imosdb.password}
        ${imosdb.initial_pool_size}
        ${imosdb.max_pool_size}
        ${imosdb.min_pool_size}
        
        
        
        
        
        
        
    

    
        
        
        
        
        
        

        
            
                classpath:static.properties
                file:static.properties
            
        

    

    

    
    
    

Java PlaceholderClass

import java.util.Properties;

import javax.sql.DataSource;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;


public class DbPropertySourcesPlaceholderConfigurer extends PropertyPlaceholderConfigurer 
{
   private static final String DEFAULT_DATASOURCENAME = "dataSource";
   private static final String DEFAULT_DBTABLENAME = "property";
   private static final String DEFAULT_DBKEYCOLUMNNAME = "key";
   private static final String DEFAULT_DBVALUECOLUMNNAME = "value";
   String dataSourceName;
   String dbTableName;
   String dbKeyColumnName;
   String dbValueColumnName;
   @Override
   public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException
   {

      DataSource dataSource = (DataSource) beanFactory.getBean(getDataSourceName());
     // DbProperties dbProps = new DbProperties(dataSource);
      final Properties dbProps = new Properties();
      dbProps.put("app.version", "v3");
      setProperties(dbProps);
      super.postProcessBeanFactory(beanFactory);
   }

   public String getDataSourceName() {
      return dataSourceName==null?DEFAULT_DATASOURCENAME:dataSourceName;
   }

   public void setDataSourceName(String dataSourceName) {
      this.dataSourceName = dataSourceName;
   }


}

Special thanks to writer of following pages.

http://ykchee.blogspot.com.tr/2012/09/spring-31-loading-properties-for-xml.html

http://blog.javaforge.net/post/31720600427/configuring-spring-based-web-application-from-database

http://www.javacodegeeks.com/2012/11/spring-3-1-loading-properties-for-xml-configuration-from-database.html