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package com.sun.source.tree;

import java.util.List;

A tree node for a case in a switch statement or expression. For example: 
  case expression :
      statements
  default :
      statements

Author:
Peter von der Ahé, Jonathan Gibbons
@jls
14.11 The switch Statement
Since:
1.6/**
 * A tree node for a {@code case} in a {@code switch} statement or expression.
 *
 * For example:
 * <pre>
 *   case <em>expression</em> :
 *       <em>statements</em>
 *
 *   default :
 *       <em>statements</em>
 * </pre>
 *
 * @jls 14.11 The switch Statement
 *
 * @author Peter von der Ah&eacute;
 * @author Jonathan Gibbons
 * @since 1.6
 */
public interface CaseTree extends Tree {
    
Returns the expression for the case, or null if this is the default case. If this case has multiple labels, returns the first label. 
Returns:
the expression for the case, or null
Deprecated:
Please use getExpressions()./**
     * Returns the expression for the case, or
     * {@code null} if this is the default case.
     * If this case has multiple labels, returns the first label.
     * @return the expression for the case, or null
     * @deprecated Please use {@link #getExpressions()}.
     */
    @Deprecated
    ExpressionTree getExpression();

    
Returns the labels for this case.
For default case, returns an empty list.
Returns:
labels for this case
Since:
12/**
     * Returns the labels for this case.
     * For default case, returns an empty list.
     *
     * @return labels for this case
     * @since 12
     */
    List<? extends ExpressionTree> getExpressions();

    
For case with kind CaseKind.STATEMENT, returns the statements labeled by the case. Returns null for case with kind CaseKind.RULE. 
Returns:
the statements labeled by the case or null/**
     * For case with kind {@linkplain CaseKind#STATEMENT},
     * returns the statements labeled by the case.
     * Returns {@code null} for case with kind
     * {@linkplain CaseKind#RULE}.
     * @return the statements labeled by the case or null
     */
    List<? extends StatementTree> getStatements();

    
For case with kind CaseKind.RULE, returns the statement or expression after the arrow. Returns null for case with kind CaseKind.STATEMENT. 
Returns:
case value or null
Since:
12/**
     * For case with kind {@linkplain CaseKind#RULE},
     * returns the statement or expression after the arrow.
     * Returns {@code null} for case with kind
     * {@linkplain CaseKind#STATEMENT}.
     *
     * @return case value or null
     * @since 12
     */
    public default Tree getBody() {
        return null;
    }

    
Returns the kind of this case.
Returns:
the kind of this case
Since:
12/**
     * Returns the kind of this case.
     *
     * @return the kind of this case
     * @since 12
     */
    public default CaseKind getCaseKind() {
        return CaseKind.STATEMENT;
    }

    
The syntatic form of this case:

    
STATEMENT: case <expression>: <statements>
    
RULE: case <expression> -> <expression>/<statement>

Since:
12/**
     * The syntatic form of this case:
     * <ul>
     *     <li>STATEMENT: {@code case <expression>: <statements>}</li>
     *     <li>RULE: {@code case <expression> -> <expression>/<statement>}</li>
     * </ul>
     *
     * @since 12
     */
    public enum CaseKind {
        
Case is in the form: case <expression>: <statements>. /**
         * Case is in the form: {@code case <expression>: <statements>}.
         */
        STATEMENT,
        
Case is in the form: case <expression> -> <expression>. /**
         * Case is in the form: {@code case <expression> -> <expression>}.
         */
        RULE;
    }
}