Package com.sun.mirror.util

Class DeclarationFilter

java.lang.Object
com.sun.mirror.util.DeclarationFilter
public class DeclarationFilter extends Object
A filter for selecting just the items of interest from a collection of declarations. The filter is said to select or to match those declarations. Filters can be created in several ways: by the static methods described below, by negating or composing existing filters, or by subclasses that implement arbitrary matching rules.

A subclass can create an arbitrary filter simply by implementing the matches(Declaration) method.

Examples.

Selecting the public declarations from a collection: 

     result = FILTER_PUBLIC.filter(decls);
Selecting class declarations (including enums): 
     classFilter = DeclarationFilter.getFilter(ClassDeclaration.class);
     result = classFilter.filter(decls);
Selecting class declarations but excluding enums: 
     enumFilter = DeclarationFilter.getFilter(EnumDeclaration.class);
     compoundFilter = classFilter.and(enumFilter.not());
     result = compoundFilter.filter(decls);
Selecting declarations named "Bob": 
     nameFilter = new DeclarationFilter() {
                      public boolean matches(Declaration d) {
                          return d.getSimpleName().equals("Bob");
                      }
                  };
     result = nameFilter.filter(decls);
Since:
1.5
Version:
1.2 04/07/19
Author:
Joseph D. Darcy, Scott Seligman

  • Field Details

    • FILTER_PUBLIC

      public static final DeclarationFilter FILTER_PUBLIC
      A filter that selects only public declarations.

    • FILTER_PROTECTED

      public static final DeclarationFilter FILTER_PROTECTED
      A filter that selects only protected declarations.

    • FILTER_PUBLIC_OR_PROTECTED

      public static final DeclarationFilter FILTER_PUBLIC_OR_PROTECTED
      A filter that selects only public or protected declarations.

    • FILTER_PACKAGE

      public static final DeclarationFilter FILTER_PACKAGE
      A filter that selects only package-private (default) declarations.

    • FILTER_PRIVATE

      public static final DeclarationFilter FILTER_PRIVATE
      A filter that selects only private declarations.

  • Constructor Details

    • DeclarationFilter

      public DeclarationFilter()
      Constructs an identity filter: one that selects all declarations.

  • Method Details

    • getFilter

      public static DeclarationFilter getFilter(Collection<Modifier> mods)
      Returns a filter that selects declarations containing all of a collection of modifiers.
      Parameters:
      mods - the modifiers to match (non-null)
      Returns:
      a filter that matches declarations containing mods

    • getFilter

      public static DeclarationFilter getFilter(Class<? extends Declaration> kind)
      Returns a filter that selects declarations of a particular kind. For example, there may be a filter that selects only class declarations, or only fields. The filter will select declarations of the specified kind, and also any subtypes of that kind; for example, a field filter will also select enum constants.
      Parameters:
      kind - the kind of declarations to select
      Returns:
      a filter that selects declarations of a particular kind

    • and

      public DeclarationFilter and(DeclarationFilter f)
      Returns a filter that selects those declarations selected by both this filter and another.
      Parameters:
      f - filter to be composed with this one
      Returns:
      a filter that selects those declarations selected by both this filter and another

    • or

      public DeclarationFilter or(DeclarationFilter f)
      Returns a filter that selects those declarations selected by either this filter or another.
      Parameters:
      f - filter to be composed with this one
      Returns:
      a filter that selects those declarations selected by either this filter or another

    • not

      public DeclarationFilter not()
      Returns a filter that selects those declarations not selected by this filter.
      Returns:
      a filter that selects those declarations not selected by this filter

    • matches

      public boolean matches(Declaration decl)
      Tests whether this filter matches a given declaration. The default implementation always returns true; subclasses should override this.
      Parameters:
      decl - the declaration to match
      Returns:
      true if this filter matches the given declaration

    • filter

      public <D extends Declaration> Collection<D> filter(Collection<D> decls)
      Returns the declarations matched by this filter. The result is a collection of the same type as the argument; the two-parameter version of filter offers control over the result type.
      Type Parameters:
      D - type of the declarations being filtered
      Parameters:
      decls - declarations being filtered
      Returns:
      the declarations matched by this filter

    • filter

      public <D extends Declaration> Collection<D> filter(Collection<? extends Declaration> decls, Class<D> resType)
      Returns the declarations matched by this filter, with the result being restricted to declarations of a given kind. Similar to the simpler single-parameter version of filter, but the result type is specified explicitly.
      Type Parameters:
      D - type of the declarations being returned
      Parameters:
      decls - declarations being filtered
      resType - type of the declarations being returned -- the reflective view of D
      Returns:
      the declarations matched by this filter, restricted to those of the specified type