/**
 * Provides a class that represents named elements in Java programs.
 */

import CompilationUnit
import semmle.code.Location
import Javadoc

/** A program element that has a name. */
class Element extends @element, Top {
  /** Holds if this element has the specified `name`. */
  predicate hasName(string name) { hasName(this, name) }

  /** Gets the name of this element. */
  string getName() { this.hasName(result) }

  /**
   * Holds if this element transitively contains the specified element `e`.
   */
  predicate contains(Element e) { this.hasChildElement+(e) }

  /**
   * Holds if this element is the immediate parent of the specified element `e`.
   *
   * It is usually preferable to use more specific predicates such as
   * `getEnclosingCallable()`, `getDeclaringType()` and/or `getEnclosingType()`
   * instead of this general predicate.
   */
  predicate hasChildElement(Element e) { hasChildElement(this, e) }

  /**
   * Holds if this element pertains to a source file.
   *
   * Elements pertaining to source files may include generated elements
   * not visible in source code, such as implicit default constructors.
   */
  predicate fromSource() { this.getCompilationUnit().getExtension() = "java" }

  /** Gets the compilation unit that this element belongs to. */
  CompilationUnit getCompilationUnit() { result = this.getFile() }

  /** Cast this element to a `Documentable`. */
  Documentable getDoc() { result = this }
}

/**
 * Holds if element `parent` is immediately above element `e` in the syntax tree.
 */
private predicate hasChildElement(Element parent, Element e) {
  cupackage(e, parent)
  or
  enclInReftype(e, parent)
  or
  not enclInReftype(e, _) and
  e.(Class).getCompilationUnit() = parent
  or
  not enclInReftype(e, _) and
  e.(Interface).getCompilationUnit() = parent
  or
  methods(e, _, _, _, parent, _)
  or
  constrs(e, _, _, _, parent, _)
  or
  params(e, _, _, parent, _)
  or
  fields(e, _, _, parent, _)
  or
  typeVars(e, _, _, _, parent)
}