8015267: Allow conversion of JS arrays to Java List/Deque

Reviewed-by: lagergren, sundar

nashorn/make/build.xml

@@ -42,8 +42,6 @@
     <condition property="hg.executable" value="/usr/local/bin/hg" else="hg">
       <available file="/usr/local/bin/hg"/>
     </condition>
-    <!-- check if JDK already has ASM classes -->
-    <available property="asm.available" classname="jdk.internal.org.objectweb.asm.Type"/>
     <!-- check if testng.jar is avaiable -->
     <available property="testng.available" file="${file.reference.testng.jar}"/>
 
@@ -80,19 +78,7 @@
     <delete dir="${dist.dir}"/>
   </target>
 
-  <!-- do it only if ASM is not available -->
-  <target name="compile-asm" depends="prepare" unless="asm.available">
-    <javac srcdir="${jdk.asm.src.dir}"
-           destdir="${build.classes.dir}"
-           excludes="**/optimizer/* **/xml/* **/attrs/*"
-           source="${javac.source}"
-           target="${javac.target}"
-           debug="${javac.debug}"
-           encoding="${javac.encoding}"
-           includeantruntime="false"/>
-  </target>
-
-  <target name="compile" depends="compile-asm" description="Compiles nashorn">
+  <target name="compile" depends="prepare" description="Compiles nashorn">
     <javac srcdir="${src.dir}"
            destdir="${build.classes.dir}"
            classpath="${javac.classpath}"

nashorn/src/jdk/nashorn/internal/objects/NativeJava.java

@@ -30,6 +30,8 @@ import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED;
 
 import java.lang.reflect.Array;
 import java.util.Collection;
+import java.util.Deque;
+import java.util.List;
 import jdk.internal.dynalink.beans.StaticClass;
 import jdk.internal.dynalink.support.TypeUtilities;
 import jdk.nashorn.internal.objects.annotations.Attribute;
@@ -37,6 +39,7 @@ import jdk.nashorn.internal.objects.annotations.Function;
 import jdk.nashorn.internal.objects.annotations.ScriptClass;
 import jdk.nashorn.internal.objects.annotations.Where;
 import jdk.nashorn.internal.runtime.JSType;
+import jdk.nashorn.internal.runtime.ListAdapter;
 import jdk.nashorn.internal.runtime.ScriptObject;
 import jdk.nashorn.internal.runtime.linker.JavaAdapterFactory;
 
@@ -240,8 +243,8 @@ public final class NativeJava {
     }
 
     /**
-     * Given a script object and a Java type, converts the script object into the desired Java type. Currently it only
-     * performs shallow creation of Java arrays, but might be extended for other types in the future. Example:
+     * Given a script object and a Java type, converts the script object into the desired Java type. Currently it
+     * performs shallow creation of Java arrays, as well as wrapping of objects in Lists and Dequeues. Example:
      * <pre>
      * var anArray = [1, "13", false]
      * var javaIntArray = Java.to(anArray, "int[]")
@@ -250,42 +253,46 @@ public final class NativeJava {
      * print(javaIntArray[2]) // prints 0, as boolean false was converted to number 0 as per ECMAScript ToNumber conversion
      * </pre>
      * @param self not used
-     * @param objArray the script object. Can be null.
+     * @param obj the script object. Can be null.
      * @param objType either a {@link #type(Object, Object) type object} or a String describing the type of the Java
      * object to create. Can not be null. If undefined, a "default" conversion is presumed (allowing the argument to be
      * omitted).
      * @return a Java object whose value corresponds to the original script object's value. Specifically, for array
      * target types, returns a Java array of the same type with contents converted to the array's component type. Does
-     * not recursively convert for multidimensional arrays.
-     * type. Returns null if scriptObject is null.
+     * not recursively convert for multidimensional arrays. For {@link List} or {@link Deque}, returns a live wrapper
+     * around the object, see {@link ListAdapter} for details. Returns null if obj is null.
      * @throws ClassNotFoundException if the class described by objType is not found
      */
     @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
-    public static Object to(final Object self, final Object objArray, final Object objType) throws ClassNotFoundException {
-        if (objArray == null) {
+    public static Object to(final Object self, final Object obj, final Object objType) throws ClassNotFoundException {
+        if (obj == null) {
             return null;
         }
 
-        final Class<?> componentType;
+        Global.checkObject(obj);
+
+        final Class<?> targetClass;
         if(objType == UNDEFINED) {
-            componentType = Object.class;
+            targetClass = Object[].class;
         } else {
-            final StaticClass arrayType;
+            final StaticClass targetType;
             if(objType instanceof StaticClass) {
-                arrayType = (StaticClass)objType;
+                targetType = (StaticClass)objType;
             } else {
-                arrayType = type(objType);
-            }
-            final Class<?> arrayClass = arrayType.getRepresentedClass();
-            if(!arrayClass.isArray()) {
-                throw typeError("to.expects.array.type", arrayClass.getName());
+                targetType = type(objType);
             }
-            componentType = arrayClass.getComponentType();
+            targetClass = targetType.getRepresentedClass();
         }
 
-        Global.checkObject(objArray);
+        if(targetClass.isArray()) {
+            return ((ScriptObject)obj).getArray().asArrayOfType(targetClass.getComponentType());
+        }
+
+        if(targetClass == List.class || targetClass == Deque.class) {
+            return new ListAdapter((ScriptObject)obj);
+        }
 
-        return ((ScriptObject)objArray).getArray().asArrayOfType(componentType);
+        throw typeError("unsupported.java.to.type", targetClass.getName());
     }
 
     /**

nashorn/src/jdk/nashorn/internal/runtime/ListAdapter.java

+package jdk.nashorn.internal.runtime;
+
+import java.util.AbstractList;
+import java.util.Deque;
+import java.util.Iterator;
+import java.util.ListIterator;
+import java.util.NoSuchElementException;
+import java.util.RandomAccess;
+import jdk.nashorn.internal.runtime.linker.InvokeByName;
+
+/**
+ * An adapter that can wrap any ECMAScript Array-like object (that adheres to the array rules for the property
+ * {@code length} and having conforming {@code push}, {@code pop}, {@code shift}, {@code unshift}, and {@code splice}
+ * methods) and expose it as both a Java list and double-ended queue. While script arrays aren't necessarily efficient
+ * as dequeues, it's still slightly more efficient to be able to translate dequeue operations into pushes, pops, shifts,
+ * and unshifts, than to blindly translate all list's add/remove operations into splices. Also, it is conceivable that a
+ * custom script object that implements an Array-like API can have a background data representation that is optimized
+ * for dequeue-like access. Note that with ECMAScript arrays, {@code push} and {@pop} operate at the end of the array,
+ * while in Java {@code Deque} they operate on the front of the queue and as such the Java dequeue {@link #push(Object)}
+ * and {@link #pop()} operations will translate to {@code unshift} and {@code shift} script operations respectively,
+ * while {@link #addLast(Object)} and {@link #removeLast()} will translate to {@code push} and {@code pop}.
+ */
+public class ListAdapter extends AbstractList<Object> implements RandomAccess, Deque<Object> {
+    // These add to the back and front of the list
+    private static final InvokeByName PUSH    = new InvokeByName("push",    ScriptObject.class, void.class, Object.class);
+    private static final InvokeByName UNSHIFT = new InvokeByName("unshift", ScriptObject.class, void.class, Object.class);
+
+    // These remove from the back and front of the list
+    private static final InvokeByName POP   = new InvokeByName("pop",   ScriptObject.class, Object.class);
+    private static final InvokeByName SHIFT = new InvokeByName("shift", ScriptObject.class, Object.class);
+
+    // These insert and remove in the middle of the list
+    private static final InvokeByName SPLICE_ADD    = new InvokeByName("splice", ScriptObject.class, void.class, int.class, int.class, Object.class);
+    private static final InvokeByName SPLICE_REMOVE = new InvokeByName("splice", ScriptObject.class, void.class, int.class, int.class);
+
+    private final ScriptObject obj;
+
+    /**
+     * Creates a new list wrapper for the specified script object.
+     * @param obj script the object to wrap
+     */
+    public ListAdapter(ScriptObject obj) {
+        this.obj = obj;
+    }
+
+    @Override
+    public int size() {
+        return JSType.toInt32(obj.getLength());
+    }
+
+    @Override
+    public Object get(int index) {
+        checkRange(index);
+        return obj.get(index);
+    }
+
+    @Override
+    public Object set(int index, Object element) {
+        checkRange(index);
+        final Object prevValue = get(index);
+        obj.set(index, element, false);
+        return prevValue;
+    }
+
+    private void checkRange(int index) {
+        if(index < 0 || index >= size()) {
+            throw invalidIndex(index);
+        }
+    }
+
+    @Override
+    public void push(Object e) {
+        addFirst(e);
+    }
+
+    @Override
+    public boolean add(Object e) {
+        addLast(e);
+        return true;
+    }
+
+    @Override
+    public void addFirst(Object e) {
+        try {
+            final Object fn = UNSHIFT.getGetter().invokeExact(obj);
+            checkFunction(fn, UNSHIFT);
+            UNSHIFT.getInvoker().invokeExact(fn, obj, e);
+        } catch(RuntimeException | Error ex) {
+            throw ex;
+        } catch(Throwable t) {
+            throw new RuntimeException(t);
+        }
+    }
+
+    @Override
+    public void addLast(Object e) {
+        try {
+            final Object fn = PUSH.getGetter().invokeExact(obj);
+            checkFunction(fn, PUSH);
+            PUSH.getInvoker().invokeExact(fn, obj, e);
+        } catch(RuntimeException | Error ex) {
+            throw ex;
+        } catch(Throwable t) {
+            throw new RuntimeException(t);
+        }
+    }
+
+    @Override
+    public void add(int index, Object e) {
+        try {
+            if(index < 0) {
+                throw invalidIndex(index);
+            } else if(index == 0) {
+                addFirst(e);
+            } else {
+                final int size = size();
+                if(index < size) {
+                    final Object fn = SPLICE_ADD.getGetter().invokeExact(obj);
+                    checkFunction(fn, SPLICE_ADD);
+                    SPLICE_ADD.getInvoker().invokeExact(fn, obj, index, 0, e);
+                } else if(index == size) {
+                    addLast(e);
+                } else {
+                    throw invalidIndex(index);
+                }
+            }
+        } catch(RuntimeException | Error ex) {
+            throw ex;
+        } catch(Throwable t) {
+            throw new RuntimeException(t);
+        }
+    }
+    private static void checkFunction(Object fn, InvokeByName invoke) {
+        if(!(fn instanceof ScriptFunction)) {
+            throw new UnsupportedOperationException("The script object doesn't have a function named " + invoke.getName());
+        }
+    }
+
+    private static IndexOutOfBoundsException invalidIndex(int index) {
+        return new IndexOutOfBoundsException(String.valueOf(index));
+    }
+
+    @Override
+    public boolean offer(Object e) {
+        return offerLast(e);
+    }
+
+    @Override
+    public boolean offerFirst(Object e) {
+        addFirst(e);
+        return true;
+    }
+
+    @Override
+    public boolean offerLast(Object e) {
+        addLast(e);
+        return true;
+    }
+
+    @Override
+    public Object pop() {
+        return removeFirst();
+    }
+
+    @Override
+    public Object remove() {
+        return removeFirst();
+    }
+
+    @Override
+    public Object removeFirst() {
+        checkNonEmpty();
+        return invokeShift();
+    }
+
+    @Override
+    public Object removeLast() {
+        checkNonEmpty();
+        return invokePop();
+    }
+
+    private void checkNonEmpty() {
+        if(isEmpty()) {
+            throw new NoSuchElementException();
+        }
+    }
+
+    @Override
+    public Object remove(int index) {
+        if(index < 0) {
+            throw invalidIndex(index);
+        } else if (index == 0) {
+            return invokeShift();
+        } else {
+            final int maxIndex = size() - 1;
+            if(index < maxIndex) {
+                final Object prevValue = get(index);
+                invokeSpliceRemove(index, 1);
+                return prevValue;
+            } else if(index == maxIndex) {
+                return invokePop();
+            } else {
+                throw invalidIndex(index);
+            }
+        }
+    }
+
+    private Object invokeShift() {
+        try {
+            final Object fn = SHIFT.getGetter().invokeExact(obj);
+            checkFunction(fn, SHIFT);
+            return SHIFT.getInvoker().invokeExact(fn, obj);
+        } catch(RuntimeException | Error ex) {
+            throw ex;
+        } catch(Throwable t) {
+            throw new RuntimeException(t);
+        }
+    }
+
+    private Object invokePop() {
+        try {
+            final Object fn = POP.getGetter().invokeExact(obj);
+            checkFunction(fn, POP);
+            return POP.getInvoker().invokeExact(fn, obj);
+        } catch(RuntimeException | Error ex) {
+            throw ex;
+        } catch(Throwable t) {
+            throw new RuntimeException(t);
+        }
+    }
+
+    @Override
+    protected void removeRange(int fromIndex, int toIndex) {
+        invokeSpliceRemove(fromIndex, toIndex - fromIndex);
+    }
+
+    private void invokeSpliceRemove(int fromIndex, int count) {
+        try {
+            final Object fn = SPLICE_REMOVE.getGetter().invokeExact(obj);
+            checkFunction(fn, SPLICE_REMOVE);
+            SPLICE_REMOVE.getInvoker().invokeExact(fn, obj, fromIndex, count);
+        } catch(RuntimeException | Error ex) {
+            throw ex;
+        } catch(Throwable t) {
+            throw new RuntimeException(t);
+        }
+    }
+
+    @Override
+    public Object poll() {
+        return pollFirst();
+    }
+
+    @Override
+    public Object pollFirst() {
+        return isEmpty() ? null : invokeShift();
+    }
+
+    @Override
+    public Object pollLast() {
+        return isEmpty() ? null : invokePop();
+    }
+
+    @Override
+    public Object peek() {
+        return peekFirst();
+    }
+
+    @Override
+    public Object peekFirst() {
+        return isEmpty() ? null : get(0);
+    }
+
+    @Override
+    public Object peekLast() {
+        return isEmpty() ? null : get(size() - 1);
+    }
+
+    @Override
+    public Object element() {
+        return getFirst();
+    }
+
+    @Override
+    public Object getFirst() {
+        checkNonEmpty();
+        return get(0);
+    }
+
+    @Override
+    public Object getLast() {
+        checkNonEmpty();
+        return get(size() - 1);
+    }
+
+    @Override
+    public Iterator<Object> descendingIterator() {
+        final ListIterator<Object> it = listIterator(size());
+        return new Iterator<Object>() {
+            @Override
+            public boolean hasNext() {
+                return it.hasPrevious();
+            }
+
+            @Override
+            public Object next() {
+                return it.previous();
+            }
+
+            @Override
+            public void remove() {
+                it.remove();
+            }
+        };
+    }
+
+    @Override
+    public boolean removeFirstOccurrence(Object o) {
+        return removeOccurrence(o, iterator());
+    }
+
+    @Override
+    public boolean removeLastOccurrence(Object o) {
+        return removeOccurrence(o, descendingIterator());
+    }
+
+    private static boolean removeOccurrence(Object o, Iterator<Object> it) {
+        while(it.hasNext()) {
+            final Object e = it.next();
+            if(o == null ? e == null : o.equals(e)) {
+                it.remove();
+                return true;
+            }
+        }
+        return false;
+    }
+}

nashorn/src/jdk/nashorn/internal/runtime/linker/InvokeByName.java

@@ -40,7 +40,7 @@ import java.lang.invoke.MethodHandle;
  *     private static final InvokeByName TO_JSON = new InvokeByName("toJSON", Object.class, Object.class, Object.class);
  *     ...
  *     final Object toJSONFn = TO_JSON.getGetter().invokeExact(obj);
- *     value = TO_JSON.getInvoker().invokeExact(toJSON, obj, key);
+ *     value = TO_JSON.getInvoker().invokeExact(toJSONFn, obj, key);
  * </pre>
  * In practice, you can have stronger type assumptions if it makes sense for your code, just remember that you must use
  * the same parameter types as the formal types of the arguments for {@code invokeExact} to work:
@@ -50,7 +50,7 @@ import java.lang.invoke.MethodHandle;
  *     final ScriptObject sobj = (ScriptObject)obj;
  *     final Object toJSONFn = TO_JSON.getGetter().invokeExact(sobj);
  *     if(toJSONFn instanceof ScriptFunction) {
- *         value = TO_JSON.getInvoker().invokeExact(toJSON, sobj, key);
+ *         value = TO_JSON.getInvoker().invokeExact(toJSONFn, sobj, key);
  *     }
  * </pre>
  * Note that in general you will not want to reuse a single instance of this class for implementing more than one call
@@ -59,6 +59,7 @@ import java.lang.invoke.MethodHandle;
  * separate instance of this class for every place.
  */
 public class InvokeByName {
+    private final String name;
     private final MethodHandle getter;
     private final MethodHandle invoker;
 
@@ -81,6 +82,7 @@ public class InvokeByName {
      * @param ptypes the parameter types of the function.
      */
     public InvokeByName(final String name, final Class<?> targetClass, final Class<?> rtype, final Class<?>... ptypes) {
+        this.name = name;
         getter  = Bootstrap.createDynamicInvoker("dyn:getMethod|getProp|getItem:" + name, Object.class, targetClass);
 
         final Class<?>[] finalPtypes;
@@ -96,6 +98,14 @@ public class InvokeByName {
         invoker = Bootstrap.createDynamicInvoker("dyn:call", rtype, finalPtypes);
     }
 
+    /**
+     * Returns the name of the function retrieved through this invoker.
+     * @return the name of the function retrieved through this invoker.
+     */
+    public String getName() {
+        return name;
+    }
+
     /**
      * Returns the property getter that can be invoked on an object to retrieve the function object that will be
      * subsequently invoked by the invoker returned by {@link #getInvoker()}.

nashorn/src/jdk/nashorn/internal/runtime/resources/Messages.properties

@@ -125,7 +125,7 @@ type.error.no.constructor.matches.args=Can not construct {0} with the passed arg
 type.error.no.method.matches.args=Can not invoke method {0} with the passed arguments; they do not match any of its method signatures.
 type.error.method.not.constructor=Java method {0} can't be used as a constructor.
 type.error.env.not.object=$ENV must be an Object.
-type.error.to.expects.array.type=Java.to() expects an array target type. {0} is not an array type.
+type.error.unsupported.java.to.type=Unsupported Java.to target type {0}.
 range.error.inappropriate.array.length=inappropriate array length: {0}
 range.error.invalid.fraction.digits=fractionDigits argument to {0} must be in [0, 20]
 range.error.invalid.precision=precision argument toPrecision() must be in [1, 21]

nashorn/test/script/basic/JDK-8015267.js

+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8015267: have a List/Deque adapter for JS array-like objects
+ *
+ * @test
+ * @run
+ */
+ 
+var a = ['a', 'b', 'c', 'd']
+
+var l = Java.to(a, java.util.List)
+print(l instanceof java.util.List)
+print(l instanceof java.util.Deque)
+
+print(l[0])
+print(l[1])
+print(l[2])
+print(l[3])
+
+print(l.size())
+
+l.push('x')
+print(a)
+
+l.addLast('y')
+print(a)
+
+print(l.pop())
+print(l.removeLast())
+print(a)
+
+l.add('e')
+l.add(5, 'f')
+print(a)
+
+l.add(0, 'z')
+print(a)
+
+l.add(2, 'x')
+print(a)
+
+l[7] = 'g'
+print(a)
+
+try { l.add(15, '') } catch(e) { print(e.class) } 
+try { l.remove(15) } catch(e) { print(e.class) } 
+try { l.add(-1, '') } catch(e) { print(e.class) } 
+try { l.remove(-1) } catch(e) { print(e.class) } 
+
+l.remove(7)
+l.remove(2)
+l.remove(0)
+print(a)
+
+print(l.peek())
+print(l.peekFirst())
+print(l.peekLast())
+
+print(l.element())
+print(l.getFirst())
+print(l.getLast())
+
+l.offer('1')
+l.offerFirst('2')
+l.offerLast('3')
+print(a)
+
+a = ['1', '2', 'x', '3', '4', 'x', '5', '6', 'x', '7', '8']
+print(a)
+var l = Java.to(a, java.util.List)
+l.removeFirstOccurrence('x')
+print(a)
+l.removeLastOccurrence('x')
+print(a)
+
+var empty = Java.to([], java.util.List)
+try { empty.pop() } catch(e) { print(e.class) }
+try { empty.removeFirst() } catch(e) { print(e.class) }
+try { empty.removeLast() } catch(e) { print(e.class) }
+
+try { empty.element() } catch(e) { print(e.class) }
+try { empty.getFirst() } catch(e) { print(e.class) }
+try { empty.getLast() } catch(e) { print(e.class) }
+
+print(empty.peek())
+print(empty.peekFirst())
+print(empty.peekLast())

nashorn/test/script/basic/JDK-8015267.js.EXPECTED

+true
+true
+a
+b
+c
+d
+4
+x,a,b,c,d
+x,a,b,c,d,y
+x
+y
+a,b,c,d
+a,b,c,d,e,f
+z,a,b,c,d,e,f
+z,a,x,b,c,d,e,f
+z,a,x,b,c,d,e,g
+class java.lang.IndexOutOfBoundsException
+class java.lang.IndexOutOfBoundsException
+class java.lang.IndexOutOfBoundsException
+class java.lang.IndexOutOfBoundsException
+a,b,c,d,e
+a
+a
+e
+a
+a
+e
+2,a,b,c,d,e,1,3
+1,2,x,3,4,x,5,6,x,7,8
+1,2,3,4,x,5,6,x,7,8
+1,2,3,4,x,5,6,7,8
+class java.util.NoSuchElementException
+class java.util.NoSuchElementException
+class java.util.NoSuchElementException
+class java.util.NoSuchElementException
+class java.util.NoSuchElementException
+class java.util.NoSuchElementException
+null
+null
+null