HistoryObject.java revision 1381:5b0c3dc04a73 
1/*
2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package jdk.nashorn.tools.jjs;
27
28import java.io.IOException;
29import java.util.Collections;
30import java.util.HashSet;
31import java.util.Set;
32import java.util.function.Function;
33import jdk.internal.jline.console.history.FileHistory;
34import jdk.internal.jline.console.history.History;
35import jdk.nashorn.api.scripting.AbstractJSObject;
36import jdk.nashorn.api.scripting.JSObject;
37import jdk.nashorn.internal.runtime.JSType;
38import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED;
39
40/*
41 * A script friendly object that exposes history of commands to scripts.
42 */
43final class HistoryObject extends AbstractJSObject {
44    private static final Set<String> props;
45    static {
46        final HashSet<String> s = new HashSet<>();
47        s.add("clear");
48        s.add("forEach");
49        s.add("print");
50        s.add("size");
51        props = Collections.unmodifiableSet(s);
52    }
53
54    private final FileHistory hist;
55
56    HistoryObject(final FileHistory hist) {
57        this.hist = hist;
58    }
59
60    @Override
61    public Object getMember(final String name) {
62        switch (name) {
63            case "clear":
64                return (Runnable)hist::clear;
65            case "forEach":
66                return (Function<JSObject, Object>)this::iterate;
67            case "print":
68                return (Runnable)this::print;
69            case "size":
70                return hist.size();
71        }
72        return UNDEFINED;
73    }
74
75    @Override
76    public Object getDefaultValue(final Class<?> hint) {
77        if (hint == String.class) {
78            return toString();
79        }
80        return UNDEFINED;
81    }
82
83    @Override
84    public String toString() {
85        return "[object history]";
86    }
87
88    @Override
89    public Set<String> keySet() {
90        return props;
91    }
92
93    private void print() {
94        for (History.Entry e : hist) {
95            System.out.println(e.value());
96        }
97    }
98
99    private Object iterate(final JSObject func) {
100        for (History.Entry e : hist) {
101            if (JSType.toBoolean(func.call(this, e.value().toString()))) {
102                break; // return true from callback to skip iteration
103            }
104        }
105        return UNDEFINED;
106    }
107}
108