Package org.springframework.core.env

Class EnumerablePropertySource<T>

java.lang.Object
org.springframework.core.env.PropertySource<T>
org.springframework.core.env.EnumerablePropertySource<T>
Type Parameters:
T - the source type
Direct Known Subclasses:
CommandLinePropertySource, CompositePropertySource, MapPropertySource, ServletConfigPropertySource, ServletContextPropertySource
public abstract class EnumerablePropertySource<T> extends PropertySource<T>
A PropertySource implementation capable of interrogating its underlying source object to enumerate all possible property name/value pairs. Exposes the getPropertyNames() method to allow callers to introspect available properties without having to access the underlying source object. This also facilitates a more efficient implementation of containsProperty(String), in that it can call getPropertyNames() and iterate through the returned array rather than attempting a call to PropertySource.getProperty(String) which may be more expensive. Implementations may consider caching the result of getPropertyNames() to fully exploit this performance opportunity.

Most framework-provided PropertySource implementations are enumerable; a counter-example would be JndiPropertySource where, due to the nature of JNDI it is not possible to determine all possible property names at any given time; rather it is only possible to try to access a property (via PropertySource.getProperty(String)) in order to evaluate whether it is present or not.

Since:
3.1
Author:
Chris Beams, Juergen Hoeller

  • Constructor Details

    • EnumerablePropertySource

      public EnumerablePropertySource(String name, T source)
      Create a new EnumerablePropertySource with the given name and source object.
      Parameters:
      name - the associated name
      source - the source object

    • EnumerablePropertySource

      protected EnumerablePropertySource(String name)
      Create a new EnumerablePropertySource with the given name and with a new Object instance as the underlying source.
      Parameters:
      name - the associated name

  • Method Details

    • containsProperty

      public boolean containsProperty(String name)
      Return whether this PropertySource contains a property with the given name.

      This implementation checks for the presence of the given name within the getPropertyNames() array.

      Overrides:
      containsProperty in class PropertySource<T>
      Parameters:
      name - the name of the property to find

    • getPropertyNames

      public abstract String[] getPropertyNames()
      Return the names of all properties contained by the source object (never null).