1 /* 2 * Copyright (c) 2010, 2013, 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 26 package jdk.nashorn.internal.objects; 27 28 import static jdk.nashorn.internal.runtime.ECMAErrors.typeError; 29 import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED; 30 31 import java.lang.invoke.MethodHandles; 32 import java.lang.reflect.Array; 33 import java.util.Collection; 34 import java.util.Deque; 35 import java.util.List; 36 import jdk.internal.dynalink.beans.StaticClass; 37 import jdk.internal.dynalink.support.TypeUtilities; 38 import jdk.nashorn.api.scripting.JSObject; 39 import jdk.nashorn.internal.objects.annotations.Attribute; 40 import jdk.nashorn.internal.objects.annotations.Function; 41 import jdk.nashorn.internal.objects.annotations.ScriptClass; 42 import jdk.nashorn.internal.objects.annotations.Where; 43 import jdk.nashorn.internal.runtime.Context; 44 import jdk.nashorn.internal.runtime.JSType; 45 import jdk.nashorn.internal.runtime.ListAdapter; 46 import jdk.nashorn.internal.runtime.PropertyMap; 47 import jdk.nashorn.internal.runtime.ScriptObject; 48 import jdk.nashorn.internal.runtime.ScriptRuntime; 49 import jdk.nashorn.internal.runtime.linker.Bootstrap; 50 import jdk.nashorn.internal.runtime.linker.JavaAdapterFactory; 51 52 /** 53 * This class is the implementation for the {@code Java} global object exposed to programs running under Nashorn. This 54 * object acts as the API entry point to Java platform specific functionality, dealing with creating new instances of 55 * Java classes, subclassing Java classes, implementing Java interfaces, converting between Java arrays and ECMAScript 56 * arrays, and so forth. 57 */ 58 @ScriptClass("Java") 59 public final class NativeJava { 60 61 // initialized by nasgen 62 @SuppressWarnings("unused") 63 private static PropertyMap $nasgenmap$; 64 65 private NativeJava() { 66 // don't create me 67 throw new UnsupportedOperationException(); 68 } 69 70 /** 71 * Returns true if the specified object is a Java type object, that is an instance of {@link StaticClass}. 72 * @param self not used 73 * @param type the object that is checked if it is a type object or not 74 * @return tells whether given object is a Java type object or not. 75 * @see #type(Object, Object) 76 */ 77 @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 78 public static boolean isType(final Object self, final Object type) { 79 return type instanceof StaticClass; 80 } 81 82 /** 83 * <p> 84 * Given a name of a Java type, returns an object representing that type in Nashorn. The Java class of the objects 85 * used to represent Java types in Nashorn is not {@link java.lang.Class} but rather {@link StaticClass}. They are 86 * the objects that you can use with the {@code new} operator to create new instances of the class as well as to 87 * access static members of the class. In Nashorn, {@code Class} objects are just regular Java objects that aren't 88 * treated specially. Instead of them, {@link StaticClass} instances - which we sometimes refer to as "Java type 89 * objects" are used as constructors with the {@code new} operator, and they expose static fields, properties, and 90 * methods. While this might seem confusing at first, it actually closely matches the Java language: you use a 91 * different expression (e.g. {@code java.io.File}) as an argument in "new" and to address statics, and it is 92 * distinct from the {@code Class} object (e.g. {@code java.io.File.class}). Below we cover in details the 93 * properties of the type objects. 94 * </p> 95 * <p><b>Constructing Java objects</b></p> 96 * Examples: 97 * <pre> 98 * var arrayListType = Java.type("java.util.ArrayList") 99 * var intType = Java.type("int") 100 * var stringArrayType = Java.type("java.lang.String[]") 101 * var int2DArrayType = Java.type("int[][]") 102 * </pre> 103 * Note that the name of the type is always a string for a fully qualified name. You can use any of these types to 104 * create new instances, e.g.: 105 * <pre> 106 * var anArrayList = new Java.type("java.util.ArrayList") 107 * </pre> 108 * or 109 * <pre> 110 * var ArrayList = Java.type("java.util.ArrayList") 111 * var anArrayList = new ArrayList 112 * var anArrayListWithSize = new ArrayList(16) 113 * </pre> 114 * In the special case of inner classes, you can either use the JVM fully qualified name, meaning using {@code $} 115 * sign in the class name, or you can use the dot: 116 * <pre> 117 * var ftype = Java.type("java.awt.geom.Arc2D$Float") 118 * </pre> 119 * and 120 * <pre> 121 * var ftype = Java.type("java.awt.geom.Arc2D.Float") 122 * </pre> 123 * both work. Note however that using the dollar sign is faster, as Java.type first tries to resolve the class name 124 * as it is originally specified, and the internal JVM names for inner classes use the dollar sign. If you use the 125 * dot, Java.type will internally get a ClassNotFoundException and subsequently retry by changing the last dot to 126 * dollar sign. As a matter of fact, it'll keep replacing dots with dollar signs until it either successfully loads 127 * the class or runs out of all dots in the name. This way it can correctly resolve and load even multiply nested 128 * inner classes with the dot notation. Again, this will be slower than using the dollar signs in the name. An 129 * alternative way to access the inner class is as a property of the outer class: 130 * <pre> 131 * var arctype = Java.type("java.awt.geom.Arc2D") 132 * var ftype = arctype.Float 133 * </pre> 134 * <p> 135 * You can access both static and non-static inner classes. If you want to create an instance of a non-static 136 * inner class, remember to pass an instance of its outer class as the first argument to the constructor. 137 * </p> 138 * <p> 139 * If the type is abstract, you can instantiate an anonymous subclass of it using an argument list that is 140 * applicable to any of its public or protected constructors, but inserting a JavaScript object with functions 141 * properties that provide JavaScript implementations of the abstract methods. If method names are overloaded, the 142 * JavaScript function will provide implementation for all overloads. E.g.: 143 * </p> 144 * <pre> 145 * var TimerTask = Java.type("java.util.TimerTask") 146 * var task = new TimerTask({ run: function() { print("Hello World!") } }) 147 * </pre> 148 * <p> 149 * Nashorn supports a syntactic extension where a "new" expression followed by an argument is identical to 150 * invoking the constructor and passing the argument to it, so you can write the above example also as: 151 * </p> 152 * <pre> 153 * var task = new TimerTask { 154 * run: function() { 155 * print("Hello World!") 156 * } 157 * } 158 * </pre> 159 * <p> 160 * which is very similar to Java anonymous inner class definition. On the other hand, if the type is an abstract 161 * type with a single abstract method (commonly referred to as a "SAM type") or all abstract methods it has share 162 * the same overloaded name), then instead of an object, you can just pass a function, so the above example can 163 * become even more simplified to: 164 * </p> 165 * <pre> 166 * var task = new TimerTask(function() { print("Hello World!") }) 167 * </pre> 168 * <p> 169 * Note that in every one of these cases if you are trying to instantiate an abstract class that has constructors 170 * that take some arguments, you can invoke those simply by specifying the arguments after the initial 171 * implementation object or function. 172 * </p> 173 * <p>The use of functions can be taken even further; if you are invoking a Java method that takes a SAM type, 174 * you can just pass in a function object, and Nashorn will know what you meant: 175 * </p> 176 * <pre> 177 * var timer = new Java.type("java.util.Timer") 178 * timer.schedule(function() { print("Hello World!") }) 179 * </pre> 180 * <p> 181 * Here, {@code Timer.schedule()} expects a {@code TimerTask} as its argument, so Nashorn creates an instance of a 182 * {@code TimerTask} subclass and uses the passed function to implement its only abstract method, {@code run()}. In 183 * this usage though, you can't use non-default constructors; the type must be either an interface, or must have a 184 * protected or public no-arg constructor. 185 * </p> 186 * <p> 187 * You can also subclass non-abstract classes; for that you will need to use the {@link #extend(Object, Object...)} 188 * method. 189 * </p> 190 * <p><b>Accessing static members</b></p> 191 * Examples: 192 * <pre> 193 * var File = Java.type("java.io.File") 194 * var pathSep = File.pathSeparator 195 * var tmpFile1 = File.createTempFile("abcdefg", ".tmp") 196 * var tmpFile2 = File.createTempFile("abcdefg", ".tmp", new File("/tmp")) 197 * </pre> 198 * Actually, you can even assign static methods to variables, so the above example can be rewritten as: 199 * <pre> 200 * var File = Java.type("java.io.File") 201 * var createTempFile = File.createTempFile 202 * var tmpFile1 = createTempFile("abcdefg", ".tmp") 203 * var tmpFile2 = createTempFile("abcdefg", ".tmp", new File("/tmp")) 204 * </pre> 205 * If you need to access the actual {@code java.lang.Class} object for the type, you can use the {@code class} 206 * property on the object representing the type: 207 * <pre> 208 * var File = Java.type("java.io.File") 209 * var someFile = new File("blah") 210 * print(File.class === someFile.getClass()) // prints true 211 * </pre> 212 * Of course, you can also use the {@code getClass()} method or its equivalent {@code class} property on any 213 * instance of the class. Other way round, you can use the synthetic {@code static} property on any 214 * {@code java.lang.Class} object to retrieve its type-representing object: 215 * <pre> 216 * var File = Java.type("java.io.File") 217 * print(File.class.static === File) // prints true 218 * </pre> 219 * <p><b>{@code instanceof} operator</b></p> 220 * The standard ECMAScript {@code instanceof} operator is extended to recognize Java objects and their type objects: 221 * <pre> 222 * var File = Java.type("java.io.File") 223 * var aFile = new File("foo") 224 * print(aFile instanceof File) // prints true 225 * print(aFile instanceof File.class) // prints false - Class objects aren't type objects. 226 * </pre> 227 * @param self not used 228 * @param objTypeName the object whose JS string value represents the type name. You can use names of primitive Java 229 * types to obtain representations of them, and you can use trailing square brackets to represent Java array types. 230 * @return the object representing the named type 231 * @throws ClassNotFoundException if the class is not found 232 */ 233 @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 234 public static Object type(final Object self, final Object objTypeName) throws ClassNotFoundException { 235 return type(objTypeName); 236 } 237 238 private static StaticClass type(final Object objTypeName) throws ClassNotFoundException { 239 return StaticClass.forClass(type(JSType.toString(objTypeName))); 240 } 241 242 private static Class<?> type(final String typeName) throws ClassNotFoundException { 243 if (typeName.endsWith("[]")) { 244 return arrayType(typeName); 245 } 246 247 return simpleType(typeName); 248 } 249 250 /** 251 * Returns name of a java type {@link StaticClass}. 252 * @param self not used 253 * @param type the type whose name is returned 254 * @return name of the given type 255 */ 256 @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 257 public static Object typeName(final Object self, final Object type) { 258 if (type instanceof StaticClass) { 259 return ((StaticClass)type).getRepresentedClass().getName(); 260 } else if (type instanceof Class) { 261 return ((Class<?>)type).getName(); 262 } else { 263 return UNDEFINED; 264 } 265 } 266 267 /** 268 * Given a script object and a Java type, converts the script object into the desired Java type. Currently it 269 * performs shallow creation of Java arrays, as well as wrapping of objects in Lists and Dequeues. Example: 270 * <pre> 271 * var anArray = [1, "13", false] 272 * var javaIntArray = Java.to(anArray, "int[]") 273 * print(javaIntArray[0]) // prints 1 274 * print(javaIntArray[1]) // prints 13, as string "13" was converted to number 13 as per ECMAScript ToNumber conversion 275 * print(javaIntArray[2]) // prints 0, as boolean false was converted to number 0 as per ECMAScript ToNumber conversion 276 * </pre> 277 * @param self not used 278 * @param obj the script object. Can be null. 279 * @param objType either a {@link #type(Object, Object) type object} or a String describing the type of the Java 280 * object to create. Can not be null. If undefined, a "default" conversion is presumed (allowing the argument to be 281 * omitted). 282 * @return a Java object whose value corresponds to the original script object's value. Specifically, for array 283 * target types, returns a Java array of the same type with contents converted to the array's component type. Does 284 * not recursively convert for multidimensional arrays. For {@link List} or {@link Deque}, returns a live wrapper 285 * around the object, see {@link ListAdapter} for details. Returns null if obj is null. 286 * @throws ClassNotFoundException if the class described by objType is not found 287 */ 288 @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 289 public static Object to(final Object self, final Object obj, final Object objType) throws ClassNotFoundException { 290 if (obj == null) { 291 return null; 292 } 293 294 if (!(obj instanceof ScriptObject) && !(obj instanceof JSObject)) { 295 throw typeError("not.an.object", ScriptRuntime.safeToString(obj)); 296 } 297 298 final Class<?> targetClass; 299 if(objType == UNDEFINED) { 300 targetClass = Object[].class; 301 } else { 302 final StaticClass targetType; 303 if(objType instanceof StaticClass) { 304 targetType = (StaticClass)objType; 305 } else { 306 targetType = type(objType); 307 } 308 targetClass = targetType.getRepresentedClass(); 309 } 310 311 if(targetClass.isArray()) { 312 return JSType.toJavaArray(obj, targetClass.getComponentType()); 313 } 314 315 if(targetClass == List.class || targetClass == Deque.class) { 316 return ListAdapter.create(obj); 317 } 318 319 throw typeError("unsupported.java.to.type", targetClass.getName()); 320 } 321 322 /** 323 * Given a Java array or {@link Collection}, returns a JavaScript array with a shallow copy of its contents. Note 324 * that in most cases, you can use Java arrays and lists natively in Nashorn; in cases where for some reason you 325 * need to have an actual JavaScript native array (e.g. to work with the array comprehensions functions), you will 326 * want to use this method. Example: 327 * <pre> 328 * var File = Java.type("java.io.File") 329 * var listHomeDir = new File("~").listFiles() 330 * var jsListHome = Java.from(listHomeDir) 331 * var jpegModifiedDates = jsListHome 332 * .filter(function(val) { return val.getName().endsWith(".jpg") }) 333 * .map(function(val) { return val.lastModified() }) 334 * </pre> 335 * @param self not used 336 * @param objArray the java array or collection. Can be null. 337 * @return a JavaScript array with the copy of Java array's or collection's contents. Returns null if objArray is 338 * null. 339 */ 340 @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 341 public static NativeArray from(final Object self, final Object objArray) { 342 if (objArray == null) { 343 return null; 344 } else if (objArray instanceof Collection) { 345 return new NativeArray(((Collection<?>)objArray).toArray()); 346 } else if (objArray instanceof Object[]) { 347 return new NativeArray(((Object[])objArray).clone()); 348 } else if (objArray instanceof int[]) { 349 return new NativeArray(((int[])objArray).clone()); 350 } else if (objArray instanceof double[]) { 351 return new NativeArray(((double[])objArray).clone()); 352 } else if (objArray instanceof long[]) { 353 return new NativeArray(((long[])objArray).clone()); 354 } else if (objArray instanceof byte[]) { 355 return new NativeArray(copyArray((byte[])objArray)); 356 } else if (objArray instanceof short[]) { 357 return new NativeArray(copyArray((short[])objArray)); 358 } else if (objArray instanceof char[]) { 359 return new NativeArray(copyArray((char[])objArray)); 360 } else if (objArray instanceof float[]) { 361 return new NativeArray(copyArray((float[])objArray)); 362 } else if (objArray instanceof boolean[]) { 363 return new NativeArray(copyArray((boolean[])objArray)); 364 } 365 366 throw typeError("cant.convert.to.javascript.array", objArray.getClass().getName()); 367 } 368 369 private static int[] copyArray(final byte[] in) { 370 final int[] out = new int[in.length]; 371 for(int i = 0; i < in.length; ++i) { 372 out[i] = in[i]; 373 } 374 return out; 375 } 376 377 private static int[] copyArray(final short[] in) { 378 final int[] out = new int[in.length]; 379 for(int i = 0; i < in.length; ++i) { 380 out[i] = in[i]; 381 } 382 return out; 383 } 384 385 private static int[] copyArray(final char[] in) { 386 final int[] out = new int[in.length]; 387 for(int i = 0; i < in.length; ++i) { 388 out[i] = in[i]; 389 } 390 return out; 391 } 392 393 private static double[] copyArray(final float[] in) { 394 final double[] out = new double[in.length]; 395 for(int i = 0; i < in.length; ++i) { 396 out[i] = in[i]; 397 } 398 return out; 399 } 400 401 private static Object[] copyArray(final boolean[] in) { 402 final Object[] out = new Object[in.length]; 403 for(int i = 0; i < in.length; ++i) { 404 out[i] = in[i]; 405 } 406 return out; 407 } 408 409 private static Class<?> simpleType(final String typeName) throws ClassNotFoundException { 410 final Class<?> primClass = TypeUtilities.getPrimitiveTypeByName(typeName); 411 if(primClass != null) { 412 return primClass; 413 } 414 final Context ctx = Global.getThisContext(); 415 try { 416 return ctx.findClass(typeName); 417 } catch(final ClassNotFoundException e) { 418 // The logic below compensates for a frequent user error - when people use dot notation to separate inner 419 // class names, i.e. "java.lang.Character.UnicodeBlock" vs."java.lang.Character$UnicodeBlock". The logic 420 // below will try alternative class names, replacing dots at the end of the name with dollar signs. 421 final StringBuilder nextName = new StringBuilder(typeName); 422 int lastDot = nextName.length(); 423 for(;;) { 424 lastDot = nextName.lastIndexOf(".", lastDot - 1); 425 if(lastDot == -1) { 426 // Exhausted the search space, class not found - rethrow the original exception. 427 throw e; 428 } 429 nextName.setCharAt(lastDot, '$'); 430 try { 431 return ctx.findClass(nextName.toString()); 432 } catch(final ClassNotFoundException cnfe) { 433 // Intentionally ignored, so the loop retries with the next name 434 } 435 } 436 } 437 438 } 439 440 private static Class<?> arrayType(final String typeName) throws ClassNotFoundException { 441 return Array.newInstance(type(typeName.substring(0, typeName.length() - 2)), 0).getClass(); 442 } 443 444 /** 445 * Returns a type object for a subclass of the specified Java class (or implementation of the specified interface) 446 * that acts as a script-to-Java adapter for it. See {@link #type(Object, Object)} for a discussion of type objects, 447 * and see {@link JavaAdapterFactory} for details on script-to-Java adapters. Note that you can also implement 448 * interfaces and subclass abstract classes using {@code new} operator on a type object for an interface or abstract 449 * class. However, to extend a non-abstract class, you will have to use this method. Example: 450 * <pre> 451 * var ArrayList = Java.type("java.util.ArrayList") 452 * var ArrayListExtender = Java.extend(ArrayList) 453 * var printSizeInvokedArrayList = new ArrayListExtender() { 454 * size: function() { print("size invoked!"); } 455 * } 456 * var printAddInvokedArrayList = new ArrayListExtender() { 457 * add: function(x, y) { 458 * if(typeof(y) === "undefined") { 459 * print("add(e) invoked!"); 460 * } else { 461 * print("add(i, e) invoked!"); 462 * } 463 * } 464 * </pre> 465 * We can see several important concepts in the above example: 466 * <ul> 467 * <li>Every specified list of Java types will have one extender subclass in Nashorn per caller protection domain - 468 * repeated invocations of {@code extend} for the same list of types for scripts same protection domain will yield 469 * the same extender type. It's a generic adapter that delegates to whatever JavaScript functions its implementation 470 * object has on a per-instance basis.</li> 471 * <li>If the Java method is overloaded (as in the above example {@code List.add()}), then your JavaScript adapter 472 * must be prepared to deal with all overloads.</li> 473 * <li>To invoke super methods from adapters, call them on the adapter instance prefixing them with {@code super$}, 474 * or use the special {@link #_super(Object, Object) super-adapter}.</li> 475 * <li>It is also possible to specify an ordinary JavaScript object as the last argument to {@code extend}. In that 476 * case, it is treated as a class-level override. {@code extend} will return an extender class where all instances 477 * will have the methods implemented by functions on that object, just as if that object were passed as the last 478 * argument to their constructor. Example: 479 * <pre> 480 * var Runnable = Java.type("java.lang.Runnable") 481 * var R1 = Java.extend(Runnable, { 482 * run: function() { 483 * print("R1.run() invoked!") 484 * } 485 * }) 486 * var r1 = new R1 487 * var t = new java.lang.Thread(r1) 488 * t.start() 489 * t.join() 490 * </pre> 491 * As you can see, you don't have to pass any object when you create a new instance of {@code R1} as its 492 * {@code run()} function was defined already when extending the class. If you also want to add instance-level 493 * overrides on these objects, you will have to repeatedly use {@code extend()} to subclass the class-level adapter. 494 * For such adapters, the order of precedence is instance-level method, class-level method, superclass method, or 495 * {@code UnsupportedOperationException} if the superclass method is abstract. If we continue our previous example: 496 * <pre> 497 * var R2 = Java.extend(R1); 498 * var r2 = new R2(function() { print("r2.run() invoked!") }) 499 * r2.run() 500 * </pre> 501 * We'll see it'll print {@code "r2.run() invoked!"}, thus overriding on instance-level the class-level behavior. 502 * Note that you must use {@code Java.extend} to explicitly create an instance-override adapter class from a 503 * class-override adapter class, as the class-override adapter class is no longer abstract. 504 * </li> 505 * </ul> 506 * @param self not used 507 * @param types the original types. The caller must pass at least one Java type object of class {@link StaticClass} 508 * representing either a public interface or a non-final public class with at least one public or protected 509 * constructor. If more than one type is specified, at most one can be a class and the rest have to be interfaces. 510 * Invoking the method twice with exactly the same types in the same order - in absence of class-level overrides - 511 * will return the same adapter class, any reordering of types or even addition or removal of redundant types (i.e. 512 * interfaces that other types in the list already implement/extend, or {@code java.lang.Object} in a list of types 513 * consisting purely of interfaces) will result in a different adapter class, even though those adapter classes are 514 * functionally identical; we deliberately don't want to incur the additional processing cost of canonicalizing type 515 * lists. As a special case, the last argument can be a {@code ScriptObject} instead of a type. In this case, a 516 * separate adapter class is generated - new one for each invocation - that will use the passed script object as its 517 * implementation for all instances. Instances of such adapter classes can then be created without passing another 518 * script object in the constructor, as the class has a class-level behavior defined by the script object. However, 519 * you can still pass a script object (or if it's a SAM type, a function) to the constructor to provide further 520 * instance-level overrides. 521 * 522 * @return a new {@link StaticClass} that represents the adapter for the original types. 523 */ 524 @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR) 525 public static Object extend(final Object self, final Object... types) { 526 if(types == null || types.length == 0) { 527 throw typeError("extend.expects.at.least.one.argument"); 528 } 529 final int l = types.length; 530 final int typesLen; 531 final ScriptObject classOverrides; 532 if(types[l - 1] instanceof ScriptObject) { 533 classOverrides = (ScriptObject)types[l - 1]; 534 typesLen = l - 1; 535 if(typesLen == 0) { 536 throw typeError("extend.expects.at.least.one.type.argument"); 537 } 538 } else { 539 classOverrides = null; 540 typesLen = l; 541 } 542 final Class<?>[] stypes = new Class<?>[typesLen]; 543 try { 544 for(int i = 0; i < typesLen; ++i) { 545 stypes[i] = ((StaticClass)types[i]).getRepresentedClass(); 546 } 547 } catch(final ClassCastException e) { 548 throw typeError("extend.expects.java.types"); 549 } 550 // Note that while the public API documentation claims self is not used, we actually use it. 551 // ScriptFunction.findCallMethod will bind the lookup object into it, and we can then use that lookup when 552 // requesting the adapter class. Note that if Java.extend is invoked with no lookup object, it'll pass the 553 // public lookup which'll result in generation of a no-permissions adapter. A typical situation this can happen 554 // is when the extend function is bound. 555 final MethodHandles.Lookup lookup; 556 if(self instanceof MethodHandles.Lookup) { 557 lookup = (MethodHandles.Lookup)self; 558 } else { 559 lookup = MethodHandles.publicLookup(); 560 } 561 return JavaAdapterFactory.getAdapterClassFor(stypes, classOverrides, lookup); 562 } 563 564 /** 565 * When given an object created using {@code Java.extend()} or equivalent mechanism (that is, any JavaScript-to-Java 566 * adapter), returns an object that can be used to invoke superclass methods on that object. E.g.: 567 * <pre> 568 * var cw = new FilterWriterAdapter(sw) { 569 * write: function(s, off, len) { 570 * s = capitalize(s, off, len) 571 * cw_super.write(s, 0, s.length()) 572 * } 573 * } 574 * var cw_super = Java.super(cw) 575 * </pre> 576 * @param self the {@code Java} object itself - not used. 577 * @param adapter the original Java adapter instance for which the super adapter is created. 578 * @return a super adapter for the original adapter 579 */ 580 @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR, name="super") 581 public static Object _super(final Object self, final Object adapter) { 582 return Bootstrap.createSuperAdapter(adapter); 583 } 584 }