Package org.flexdock.util

Class NestedComponents

java.lang.Object
org.flexdock.util.NestedComponents
public class NestedComponents extends Object
This is a utility class for small, short-lived object instances used to find nested Components. It models a relationship between nested Components within an AWT Container hierarchy such that, given a starting Component from which to search, it will find two Components nested within each other of specific class types. The "deeper" component will be a descendent of the "parent" component.

For example, given a JTextField within a content frame, the application logic may need to check to see if the text field resides within a certain application-specific container set. Perhaps all JTables embedded within JSplitPanes are significant within the particular application. The find(Component searchSrc, Class childClass, Class parentClass) method on this class will be able to return a NestedComponents instance indicating whether the specified text field resides within a JTable that is embedded within a JSplitPane.

Although perhaps a bit contrived, this example shows a generic use for this class. The FlexDock framework itself has a particular interest in Dockable components that are embedded within DockingPorts, especially during drag operations. As a Dockable is dragged over an DockingPort, this class allows the framework to determine with a single object instance any Dockables currently embedded within the target DockingPort, starting with the deepest Component at the current mouse point during the drag.

This classes' member fields are public and may be both accessed and modified by external code as needed within their particular usage context. This is by design for ease of use within the FlexDock framework. Consequently, instances of this class should only be used for short-lived operations. Since its member fields may be modified publicly, instances of this class should not be cached, nor should its member values be indexed as they are subject to arbitrary changes over the long term.

Author:
Christopher Butler

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    Component
    child
     
    Component
    parent
     
    Component
    searchSrc
     

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    equals(Object obj)
    Returns true if the specified Object is a NestedComponents instance and all shares all of the same field references (==) as this NestedComponents for field searchSrc, child, and parent.
    static NestedComponents
    find(Component searchSrc, Class childClass, Class parentClass)
    Creates and returns a new NestedComponents instance, searching the parent Container hierarcy of the specified searchSrc for an ancestor of type childClass and a more senior ancestor of type parentClass.
    int
    hashCode()
    Overridden to match the equals() method.
    boolean
    isFull()
    Returns true if both child and parent fields are non-null; false otherwise.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

  • Field Details

  • Method Details

    • find

      public static NestedComponents find(Component searchSrc, Class childClass, Class parentClass)
      Creates and returns a new NestedComponents instance, searching the parent Container hierarcy of the specified searchSrc for an ancestor of type childClass and a more senior ancestor of type parentClass.

      If either searchSrc, childClass, or parentClass is null, this method returns null.

      If searchSrc is an instanceof childClass, then the child field on the resulting NestedComponents will be equal (==) to the searchSrc field. If searchSrc is an instanceof parentClass, then the parent field on the resulting NestedComponents will be equal (==) to the searchSrc field. If an instance of parentClass is found before childClass, this the resulting NestedComponents instance will have a null child field.

      Parameters:
      searchSrc - the Component from which to start searching for parent Containers.
      childClass - the Class of the desired "child" Component
      parentClass - the Class of the desired "parent" Component
      Returns:
      a new NestedComponents instance based upon the specified parameters.

    • isFull

      public boolean isFull()
      Returns true if both child and parent fields are non-null; false otherwise.
      Returns:
      true if both child and parent fields are non-null; false otherwise.

    • hashCode

      public int hashCode()
      Overridden to match the equals() method.
      Overrides:
      hashCode in class Object
      Returns:
      a hash code value for this object.
      See Also:

    • equals

      public boolean equals(Object obj)
      Returns true if the specified Object is a NestedComponents instance and all shares all of the same field references (==) as this NestedComponents for field searchSrc, child, and parent.
      Overrides:
      equals in class Object
      Parameters:
      obj - the Object to test for equality
      Returns:
      true if the specified Object is "equal" to this NestedComponents instance; false otherwise.