langtools/src/jdk.jshell/share/classes/jdk/jshell/ExpressionSnippet.java
author jlahoda
Mon, 19 Oct 2015 19:15:16 +0200
changeset 33362 65ec6de1d6b4
child 34752 9c262a013456
permissions -rw-r--r--
8134254: JShell API/tool: REPL for Java into JDK9 Summary: Adding the implementation of the jshell (read-eval-print-loop) tool. Reviewed-by: briangoetz, mcimadamore, psandoz, forax Contributed-by: robert.field@oracle.com, bitterfoxc@gmail.com, jan.lahoda@oracle.com

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package jdk.jshell;

import jdk.jshell.Key.ExpressionKey;

/**
 * Snippet for an assignment or variable-value expression.
 * The Kind is {@link jdk.jshell.Snippet.Kind#EXPRESSION}.
 * <p>
 * <code>ExpressionSnippet</code> is immutable: an access to
 * any of its methods will always return the same result.
 * and thus is thread-safe.
 * @jls 15: Expression.
 */
public class ExpressionSnippet extends Snippet {

    ExpressionSnippet(ExpressionKey key, String userSource, Wrap guts, String name, SubKind subkind) {
        super(key, userSource, guts, name, subkind);
    }

    /**
     * Variable name which is the value of the expression. Since the expression
     * is either just a variable identifier or it is an assignment
     * to a variable, there is always a variable which is the subject of the
     * expression. All other forms of expression become temporary variables
     * which are instead referenced by a {@link VarSnippet}.
     * @return the name of the variable which is the subject of the expression.
     */
    @Override
    public String name() {
        return key().name();
    }

    /**
     * Type of the expression
     * @return String representation of the type of the expression.
     */
    public String typeName() {
        return key().typeName();
    }

    /**** internal access ****/

    @Override
    ExpressionKey key() {
        return (ExpressionKey) super.key();
    }
}