Apache Commons BeanUtils

From Java Example Source Code

[edit] Overview Apache Commons BeanUtils

Most Java developers are used to creating Java classes that conform to the JavaBeans naming patterns for property getters and setters. It is natural to then access these methods directly, using calls to the corresponding getXxx and setXxx methods. However, there are some occasions where dynamic access to Java object properties (without compiled-in knowledge of the property getter and setter methods to be called) is needed. Example use cases include:

• Building scripting languages that interact with the Java object model (such as the Bean Scripting Framework).
• Building template language processors for web presentation and similar uses (such as JSP or Velocity).
• Building custom tag libraries for JSP and XSP environments (such as Jakarta Taglibs, Struts, Cocoon).
• Consuming XML-based configuration resources (such as Ant build scripts, web application deployment descriptors, Tomcat's server.xml file).

The Java language provides Reflection and Introspection APIs (see the java.lang.reflect and java.beans packages in the JDK Javadocs). However, these APIs can be quite complex to understand and utilize. The BeanUtils component provides easy-to-use wrappers around these capabilities.

For example:

    public class Employee {
        public Address getAddress(String type);
        public void setAddress(String type, Address address);
        public Employee getSubordinate(int index);
        public void setSubordinate(int index, Employee subordinate);
        public String getFirstName();
        public void setFirstName(String firstName);
        public String getLastName();
        public void setLastName(String lastName);
    }

you can get the 'firstName' by PropertyUtils.getSimpleProperty:

    String firstName = (String)
      PropertyUtils.getSimpleProperty(employee, "firstName");
    String lastName = (String)
      PropertyUtils.getSimpleProperty(employee, "lastName");

[edit] Apache Commons BeanUtils Resources

• Web site: http://commons.apache.org/beanutils/
• Java API: BeanUtils 1.7 API
• Examples: Apache Commons BeanUtils by exampes
• Tutorial:
• News or Forums: