NativeMap.java
/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.javascript;
import java.util.List;
import java.util.Map;
public class NativeMap extends ScriptableObject {
private static final long serialVersionUID = 1171922614280016891L;
private static final String CLASS_NAME = "Map";
static final String ITERATOR_TAG = "Map Iterator";
private final Hashtable entries = new Hashtable();
private boolean instanceOfMap = false;
static Object init(Context cx, Scriptable scope, boolean sealed) {
LambdaConstructor constructor =
new LambdaConstructor(
scope,
CLASS_NAME,
0,
LambdaConstructor.CONSTRUCTOR_NEW,
NativeMap::jsConstructor);
constructor.setPrototypePropertyAttributes(DONTENUM | READONLY | PERMANENT);
constructor.defineConstructorMethod(scope, "groupBy", 2, NativeMap::jsGroupBy, DONTENUM);
constructor.definePrototypeMethod(
scope,
"set",
2,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "set")
.js_set(key(args), args.length > 1 ? args[1] : Undefined.instance),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"delete",
1,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "delete").js_delete(key(args)),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"get",
1,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "get").js_get(key(args)),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"has",
1,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "has").js_has(key(args)),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"clear",
0,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "clear").js_clear(),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"keys",
0,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "keys")
.js_iterator(scope, NativeCollectionIterator.Type.KEYS),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"values",
0,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "values")
.js_iterator(scope, NativeCollectionIterator.Type.VALUES),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"forEach",
1,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "forEach")
.js_forEach(
lcx,
lscope,
args.length > 0 ? args[0] : Undefined.instance,
args.length > 1 ? args[1] : Undefined.instance),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeMethod(
scope,
"entries",
0,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "entries")
.js_iterator(scope, NativeCollectionIterator.Type.BOTH),
DONTENUM,
DONTENUM | READONLY);
constructor.definePrototypeAlias("entries", SymbolKey.ITERATOR, DONTENUM);
// The spec requires very specific handling of the "size" prototype
// property that's not like other things that we already do.
ScriptableObject desc = (ScriptableObject) cx.newObject(scope);
desc.put("enumerable", desc, Boolean.FALSE);
desc.put("configurable", desc, Boolean.TRUE);
LambdaFunction sizeFunc =
new LambdaFunction(
scope,
"get size",
0,
(Context lcx, Scriptable lscope, Scriptable thisObj, Object[] args) ->
realThis(thisObj, "size").js_getSize());
sizeFunc.setPrototypeProperty(Undefined.instance);
desc.put("get", desc, sizeFunc);
constructor.definePrototypeProperty(cx, "size", desc);
constructor.definePrototypeProperty(cx, NativeSet.GETSIZE, desc);
constructor.definePrototypeProperty(
SymbolKey.TO_STRING_TAG, CLASS_NAME, DONTENUM | READONLY);
ScriptRuntimeES6.addSymbolSpecies(cx, scope, constructor);
if (sealed) {
constructor.sealObject();
((ScriptableObject) constructor.getPrototypeProperty()).sealObject();
}
return constructor;
}
@Override
public String getClassName() {
return CLASS_NAME;
}
private static Scriptable jsConstructor(Context cx, Scriptable scope, Object[] args) {
NativeMap nm = new NativeMap();
nm.instanceOfMap = true;
if (args.length > 0) {
loadFromIterable(cx, scope, nm, key(args));
}
return nm;
}
private static Object jsGroupBy(
Context cx, Scriptable scope, Scriptable thisObj, Object[] args) {
Object items = args.length < 1 ? Undefined.instance : args[0];
Object callback = args.length < 2 ? Undefined.instance : args[1];
Map<Object, List<Object>> groups =
AbstractEcmaObjectOperations.groupBy(
cx,
scope,
CLASS_NAME,
"groupBy",
items,
callback,
AbstractEcmaObjectOperations.KEY_COERCION.COLLECTION);
NativeMap map = (NativeMap) cx.newObject(scope, "Map");
for (Map.Entry<Object, List<Object>> entry : groups.entrySet()) {
Scriptable elements = cx.newArray(scope, entry.getValue().toArray());
map.entries.put(entry.getKey(), elements);
}
return map;
}
private Object js_set(Object k, Object v) {
// Special handling of "negative zero" from the spec.
Object key = k;
if ((key instanceof Number) && ((Number) key).doubleValue() == ScriptRuntime.negativeZero) {
key = ScriptRuntime.zeroObj;
}
entries.put(key, v);
return this;
}
private Object js_delete(Object arg) {
return entries.deleteEntry(arg);
}
private Object js_get(Object arg) {
final Hashtable.Entry entry = entries.getEntry(arg);
if (entry == null) {
return Undefined.instance;
}
return entry.value;
}
private Object js_has(Object arg) {
return entries.has(arg);
}
private Object js_getSize() {
return entries.size();
}
private Object js_iterator(Scriptable scope, NativeCollectionIterator.Type type) {
return new NativeCollectionIterator(scope, ITERATOR_TAG, type, entries.iterator());
}
private Object js_clear() {
entries.clear();
return Undefined.instance;
}
private Object js_forEach(Context cx, Scriptable scope, Object arg1, Object arg2) {
if (!(arg1 instanceof Callable)) {
throw ScriptRuntime.typeErrorById(
"msg.isnt.function", arg1, ScriptRuntime.typeof(arg1));
}
final Callable f = (Callable) arg1;
boolean isStrict = cx.isStrictMode();
for (Hashtable.Entry entry : entries) {
// Per spec must convert every time so that primitives are always regenerated...
Scriptable thisObj = ScriptRuntime.toObjectOrNull(cx, arg2, scope);
if (thisObj == null && !isStrict) {
thisObj = scope;
}
if (thisObj == null) {
thisObj = Undefined.SCRIPTABLE_UNDEFINED;
}
final Hashtable.Entry e = entry;
f.call(cx, scope, thisObj, new Object[] {e.value, e.key, this});
}
return Undefined.instance;
}
/**
* If an "iterable" object was passed to the constructor, there are many many things to do...
* Make this static because NativeWeakMap has the exact same requirement.
*/
static void loadFromIterable(Context cx, Scriptable scope, ScriptableObject map, Object arg1) {
if ((arg1 == null) || Undefined.instance.equals(arg1)) {
return;
}
// Call the "[Symbol.iterator]" property as a function.
final Object ito = ScriptRuntime.callIterator(arg1, cx, scope);
if (Undefined.instance.equals(ito)) {
// Per spec, ignore if the iterator is undefined
return;
}
// Find the "add" function of our own prototype, since it might have
// been replaced. Since we're not fully constructed yet, create a dummy instance
// so that we can get our own prototype.
Scriptable proto = ScriptableObject.getClassPrototype(scope, map.getClassName());
var setCall = ScriptRuntime.getPropAndThis(proto, "set", cx, scope);
Callable set = setCall.getCallable();
ScriptRuntime.loadFromIterable(
cx,
scope,
arg1,
(key, value) -> set.call(cx, scope, map, new Object[] {key, value}));
}
private static NativeMap realThis(Scriptable thisObj, String name) {
NativeMap nm = LambdaConstructor.convertThisObject(thisObj, NativeMap.class);
if (!nm.instanceOfMap) {
// Check for "Map internal data tag"
throw ScriptRuntime.typeErrorById("msg.incompat.call", name);
}
return nm;
}
/**
* Extracts the key from the first args entry if any and takes care of the Delegator. This is
* used by {@code NativeSet}, {@code NativeWeakMap}, and {@code NativeWekSet} also.
*
* @param args the args
* @return the first argument (de-delegated) or undefined if there is no element in args
*/
static Object key(Object[] args) {
if (args.length > 0) {
Object key = args[0];
if (key instanceof Delegator) {
return ((Delegator) key).getDelegee();
}
return key;
}
return Undefined.instance;
}
}