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package javax.lang.model.util;
import javax.lang.model.element.*;
import javax.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import static javax.lang.model.SourceVersion.*;
A scanning visitor of program elements with default behavior appropriate for the RELEASE_8
source version. The visitXyz
methods in this class scan their component elements by calling scan
on their enclosed elements, parameters, etc., as indicated in the individual method specifications. A subclass can control the order elements are visited by overriding the visitXyz
methods. Note that clients of a scanner may get the desired behavior be invoking v.scan(e, p)
rather than v.visit(e, p)
on the root objects of interest. When a subclass overrides a visitXyz
method, the
new method can cause the enclosed elements to be scanned in the
default way by calling super.visitXyz
. In this
fashion, the concrete visitor can control the ordering of traversal
over the component elements with respect to the additional
processing; for example, consistently calling
super.visitXyz
at the start of the overridden
methods will yield a preorder traversal, etc. If the component
elements should be traversed in some other order, instead of
calling super.visitXyz
, an overriding visit method should call scan
with the elements in the desired order.
Type parameters: See Also: API Note:
Methods in this class may be overridden subject to their general
contract. Since: 1.8
/**
* A scanning visitor of program elements with default behavior
* appropriate for the {@link SourceVersion#RELEASE_8 RELEASE_8}
* source version. The <code>visit<i>Xyz</i></code> methods in this
* class scan their component elements by calling {@code scan} on
* their {@linkplain Element#getEnclosedElements enclosed elements},
* {@linkplain ExecutableElement#getParameters parameters}, etc., as
* indicated in the individual method specifications. A subclass can
* control the order elements are visited by overriding the
* <code>visit<i>Xyz</i></code> methods. Note that clients of a scanner
* may get the desired behavior be invoking {@code v.scan(e, p)} rather
* than {@code v.visit(e, p)} on the root objects of interest.
*
* <p>When a subclass overrides a <code>visit<i>Xyz</i></code> method, the
* new method can cause the enclosed elements to be scanned in the
* default way by calling <code>super.visit<i>Xyz</i></code>. In this
* fashion, the concrete visitor can control the ordering of traversal
* over the component elements with respect to the additional
* processing; for example, consistently calling
* <code>super.visit<i>Xyz</i></code> at the start of the overridden
* methods will yield a preorder traversal, etc. If the component
* elements should be traversed in some other order, instead of
* calling <code>super.visit<i>Xyz</i></code>, an overriding visit method
* should call {@code scan} with the elements in the desired order.
*
* @apiNote
* Methods in this class may be overridden subject to their general
* contract.
*
* @param <R> the return type of this visitor's methods. Use {@link
* Void} for visitors that do not need to return results.
* @param <P> the type of the additional parameter to this visitor's
* methods. Use {@code Void} for visitors that do not need an
* additional parameter.
*
* @see <a href="ElementScanner6.html#note_for_subclasses"><strong>Compatibility note for subclasses</strong></a>
* @see ElementScanner6
* @see ElementScanner7
* @see ElementScanner9
* @see ElementScanner14
* @since 1.8
*/
@SupportedSourceVersion(RELEASE_8)
public class ElementScanner8<R, P> extends ElementScanner7<R, P> {
Constructor for concrete subclasses; uses null
for the default value. /**
* Constructor for concrete subclasses; uses {@code null} for the
* default value.
*/
@SuppressWarnings("deprecation") // Superclass constructor deprecated
protected ElementScanner8(){
super(null);
}
Constructor for concrete subclasses; uses the argument for the
default value.
Params: - defaultValue – the default value
/**
* Constructor for concrete subclasses; uses the argument for the
* default value.
*
* @param defaultValue the default value
*/
@SuppressWarnings("deprecation") // Superclass constructor deprecated
protected ElementScanner8(R defaultValue){
super(defaultValue);
}
}