You need to access a nested bean property.

Use PropertyUtils.getNestedProperty() to retrieve a nested bean property. Use a period as a delimiter to identify nested bean properties; one.two.three.four refers to a property nested three levels deep—the four property of the three property of the two property of the one property. The following example accesses a nested bean property on a Person bean, author.name:

import org.apache.commons.beanutils.PropertyUtils;

Book book = new Book( );
book.setName( "Emerson's Essays" );

Person author = new Person( );
author.setName( "Ralph Waldo Emerson" );
book.setAuthor( author );

String authorName = (String) PropertyUtils.getNestedProperty(book, "author.name");
System.out.println( "authorName" );This example retrieves the name 
property of the author property on the Book object, printing "Ralph 
Waldo Emerson".

The author property of Book is a Person bean with a name property; calling getNestedProperty( ) with author.name retrieves the simple property author from Book and the property name, which is nested in the author property. Figure 3-3 shows the Book and Person beans that were used in the previous example.

Figure 3-3. Structure of two simple beans: Book and Person

The following example demonstrates a combination of getSimpleProperty( ) and getNestedProperty( ), retrieving a book name and an author name:

General Exception is caught.

import org.apache.commons.beanutils.PropertyUtils;

// Create an author
Person author = new Person( );
author.setName( "Chaucer" );

Book book = new Book( );
book.setName( "The Canterbury Tales" );
book.setAuthor( author );

try {
    String bookName = (String) PropertyUtils.getSimpleProperty( book, "name" );
                   String authorName = 
                       (String) PropertyUtils.getNestedProperty( book, "author.name" );

    System.out.println( "The book is " + bookName );
    System.out.println( "The author is " + authorName );

} catch (Exception e) {
    System.out.println( "There was a problem getting a bean property." );
    e.printStackTrace( );
}

When using getNestedProperty( ), there is no limit to the number of nesting levels for a property; demonstrating the retrieval of a deeply nested property, the following example retrieves the name property from the state property of the address property of a Person object:

String propertyName = "address.state.name";

String stateName =
                   (String) PropertyUtils.getNestedProperty( person,  propertyName );

This example assumes that the Person class has a getAddress( ) method that returns an Address object with a getState( ) method and returns a State object with a getName() method. The emphasized code in the previous example is the equivalent of the following three lines of code:

Address address = person.getAddress( );
State state = address.getState( );
String stateName = state.getName( );