1 /*
2 * Copyright (c) 2015, 2016, 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 /* @test
27 * @bug 8139885
28 * @bug 8150635
29 * @bug 8150956
30 * @bug 8150957
31 * @bug 8152667
32 * @bug 8153637
33 * @bug 8154751
34 * @run testng/othervm -ea -esa test.java.lang.invoke.LoopCombinatorTest
35 */
36
37 package test.java.lang.invoke;
38
39 import java.lang.invoke.MethodHandle;
40 import java.lang.invoke.MethodHandles;
41 import java.lang.invoke.MethodHandles.Lookup;
42 import java.lang.invoke.MethodType;
43 import java.util.*;
44
45 import static java.lang.invoke.MethodType.methodType;
46
47 import static org.testng.AssertJUnit.*;
48
49 import org.testng.annotations.*;
50
51 /**
52 * Tests for the loop combinators introduced in JEP 274.
53 */
54 public class LoopCombinatorTest {
55
56 static final Lookup LOOKUP = MethodHandles.lookup();
57
58 @Test
59 public static void testLoopFac() throws Throwable {
60 MethodHandle[] counterClause = new MethodHandle[]{Fac.MH_zero, Fac.MH_inc};
61 MethodHandle[] accumulatorClause = new MethodHandle[]{Fac.MH_one, Fac.MH_mult, Fac.MH_pred, Fac.MH_fin};
62 MethodHandle loop = MethodHandles.loop(counterClause, accumulatorClause);
63 assertEquals(Fac.MT_fac, loop.type());
64 assertEquals(120, loop.invoke(5));
65 }
66
67 @Test
68 public static void testLoopFacNullInit() throws Throwable {
69 // null initializer for counter, should initialize to 0
70 MethodHandle[] counterClause = new MethodHandle[]{null, Fac.MH_inc};
71 MethodHandle[] accumulatorClause = new MethodHandle[]{Fac.MH_one, Fac.MH_mult, Fac.MH_pred, Fac.MH_fin};
72 MethodHandle loop = MethodHandles.loop(counterClause, accumulatorClause);
73 assertEquals(Fac.MT_fac, loop.type());
74 assertEquals(120, loop.invoke(5));
75 }
76
77 @Test
78 public static void testLoopNullInit() throws Throwable {
79 // null initializer for counter, should initialize to 0, one-clause loop
80 MethodHandle[] counterClause = new MethodHandle[]{null, Loop.MH_inc, Loop.MH_pred, Loop.MH_fin};
81 MethodHandle loop = MethodHandles.loop(counterClause);
82 assertEquals(Loop.MT_loop, loop.type());
83 assertEquals(10, loop.invoke(10));
84 }
85
86 @Test
87 public static void testLoopVoid1() throws Throwable {
88 // construct a post-checked loop that only does one iteration and has a void body and void local state
89 MethodHandle loop = MethodHandles.loop(new MethodHandle[]{Empty.MH_f, Empty.MH_f, Empty.MH_pred, null});
90 assertEquals(MethodType.methodType(void.class), loop.type());
91 loop.invoke();
92 }
93
94 @Test
95 public static void testLoopVoid2() throws Throwable {
96 // construct a post-checked loop that only does one iteration and has a void body and void local state,
97 // initialized implicitly from the step type
98 MethodHandle loop = MethodHandles.loop(new MethodHandle[]{null, Empty.MH_f, Empty.MH_pred, null});
99 assertEquals(MethodType.methodType(void.class), loop.type());
100 loop.invoke();
101 }
102
103 @Test
104 public static void testLoopVoid3() throws Throwable {
105 // construct a post-checked loop that only does one iteration and has a void body and void local state,
106 // and that has a void finalizer
107 MethodHandle loop = MethodHandles.loop(new MethodHandle[]{null, Empty.MH_f, Empty.MH_pred, Empty.MH_f});
108 assertEquals(MethodType.methodType(void.class), loop.type());
109 loop.invoke();
110 }
111
112 @Test
113 public static void testLoopFacWithVoidState() throws Throwable {
114 // like testLoopFac, but with additional void state that outputs a dot
115 MethodHandle[] counterClause = new MethodHandle[]{Fac.MH_zero, Fac.MH_inc};
116 MethodHandle[] accumulatorClause = new MethodHandle[]{Fac.MH_one, Fac.MH_mult, Fac.MH_pred, Fac.MH_fin};
117 MethodHandle[] dotClause = new MethodHandle[]{null, Fac.MH_dot};
118 MethodHandle loop = MethodHandles.loop(counterClause, accumulatorClause, dotClause);
119 assertEquals(Fac.MT_fac, loop.type());
120 assertEquals(120, loop.invoke(5));
121 }
122
123 @Test
124 public static void testLoopVoidInt() throws Throwable {
125 // construct a post-checked loop that only does one iteration and has a void body and void local state,
126 // and that returns a constant
127 MethodHandle loop = MethodHandles.loop(new MethodHandle[]{null, Empty.MH_f, Empty.MH_pred, Empty.MH_c});
128 assertEquals(MethodType.methodType(int.class), loop.type());
129 assertEquals(23, loop.invoke());
130 }
131
132 @Test
133 public static void testLoopWithVirtuals() throws Throwable {
134 // construct a loop (to calculate factorial) that uses a mix of static and virtual methods
135 MethodHandle[] counterClause = new MethodHandle[]{null, LoopWithVirtuals.permute(LoopWithVirtuals.MH_inc)};
136 MethodHandle[] accumulatorClause = new MethodHandle[]{
137 // init function must indicate the loop arguments (there is no other means to determine them)
138 MethodHandles.dropArguments(LoopWithVirtuals.MH_one, 0, LoopWithVirtuals.class),
139 LoopWithVirtuals.permute(LoopWithVirtuals.MH_mult),
140 LoopWithVirtuals.permute(LoopWithVirtuals.MH_pred),
141 LoopWithVirtuals.permute(LoopWithVirtuals.MH_fin)
142 };
143 MethodHandle loop = MethodHandles.loop(counterClause, accumulatorClause);
144 assertEquals(LoopWithVirtuals.MT_loop, loop.type());
145 assertEquals(120, loop.invoke(new LoopWithVirtuals(), 5));
146 }
147
148 @DataProvider
149 static Object[][] negativeTestData() {
150 MethodHandle i0 = MethodHandles.constant(int.class, 0);
151 MethodHandle ii = MethodHandles.dropArguments(i0, 0, int.class, int.class);
152 MethodHandle id = MethodHandles.dropArguments(i0, 0, int.class, double.class);
153 MethodHandle i3 = MethodHandles.dropArguments(i0, 0, int.class, int.class, int.class);
154 List<MethodHandle> inits = Arrays.asList(ii, id, i3);
155 List<Class<?>> ints = Arrays.asList(int.class, int.class, int.class);
156 List<MethodHandle> finis = Arrays.asList(Fac.MH_fin, Fac.MH_inc, Counted.MH_step);
157 List<MethodHandle> preds1 = Arrays.asList(null, null, null);
158 List<MethodHandle> preds2 = Arrays.asList(null, Fac.MH_fin, null);
159 MethodHandle eek = MethodHandles.dropArguments(i0, 0, int.class, int.class, double.class);
160 List<MethodHandle> nesteps = Arrays.asList(Fac.MH_inc, eek, Fac.MH_dot);
161 List<MethodHandle> nepreds = Arrays.asList(null, Fac.MH_pred, null);
162 List<MethodHandle> nefinis = Arrays.asList(null, Fac.MH_fin, null);
163 List<MethodHandle> lvsteps = Arrays.asList(LoopWithVirtuals.MH_inc, LoopWithVirtuals.MH_mult);
164 List<MethodHandle> lvpreds = Arrays.asList(null, LoopWithVirtuals.MH_pred);
165 List<MethodHandle> lvfinis = Arrays.asList(null, LoopWithVirtuals.MH_fin);
166 return new Object[][] {
167 {null, "null or no clauses passed"},
168 {new MethodHandle[][]{}, "null or no clauses passed"},
169 {new MethodHandle[][]{{null, Fac.MH_inc}, {Fac.MH_one, null, Fac.MH_mult, Fac.MH_pred, Fac.MH_fin}},
170 "All loop clauses must be represented as MethodHandle arrays with at most 4 elements."},
171 {new MethodHandle[][]{{null, Fac.MH_inc}, null}, "null clauses are not allowed"},
172 {new MethodHandle[][]{{Fac.MH_zero, Fac.MH_dot}},
173 "clause 0: init and step return types must match: int != void"},
174 {new MethodHandle[][]{{ii}, {id}, {i3}},
175 "found non-effectively identical init parameter type lists: " + inits +
176 " (common suffix: " + ints + ")"},
177 {new MethodHandle[][]{{null, Fac.MH_inc, null, Fac.MH_fin}, {null, Fac.MH_inc, null, Fac.MH_inc},
178 {null, Counted.MH_start, null, Counted.MH_step}},
179 "found non-identical finalizer return types: " + finis + " (return type: int)"},
180 {new MethodHandle[][]{{Fac.MH_zero, Fac.MH_inc}, {Fac.MH_one, Fac.MH_mult, null, Fac.MH_fin},
181 {null, Fac.MH_dot}}, "no predicate found: " + preds1},
182 {new MethodHandle[][]{{Fac.MH_zero, Fac.MH_inc}, {Fac.MH_one, Fac.MH_mult, Fac.MH_fin, Fac.MH_fin},
183 {null, Fac.MH_dot}}, "predicates must have boolean return type: " + preds2},
184 {new MethodHandle[][]{{Fac.MH_zero, Fac.MH_inc}, {Fac.MH_one, eek, Fac.MH_pred, Fac.MH_fin},
185 {null, Fac.MH_dot}},
186 "found non-effectively identical parameter type lists:\nstep: " + nesteps +
187 "\npred: " + nepreds + "\nfini: " + nefinis + " (common parameter sequence: " + ints + ")"},
188 {new MethodHandle[][]{{null, LoopWithVirtuals.MH_inc},
189 {LoopWithVirtuals.MH_one, LoopWithVirtuals.MH_mult, LoopWithVirtuals.MH_pred, LoopWithVirtuals.MH_fin}},
190 "found non-effectively identical parameter type lists:\nstep: " + lvsteps +
191 "\npred: " + lvpreds + "\nfini: " + lvfinis + " (common parameter sequence: " + ints + ")"}
192 };
193 }
194
195 static final MethodHandle MH_loop;
196
197 static {
198 try {
199 MH_loop = LOOKUP.findStatic(MethodHandles.class, "loop", methodType(MethodHandle.class, MethodHandle[][].class));
200 } catch (NoSuchMethodException | IllegalAccessException e) {
201 throw new ExceptionInInitializerError(e);
202 }
203 }
204
205 @Test(dataProvider = "negativeTestData")
206 public static void testLoopNegative(MethodHandle[][] clauses, String expectedMessage) throws Throwable {
207 boolean caught = false;
208 try {
209 MH_loop.invokeWithArguments(clauses);
210 } catch (IllegalArgumentException iae) {
211 assertEquals(expectedMessage, iae.getMessage());
212 caught = true;
213 }
214 assertTrue(caught);
215 }
216
217 @Test
218 public static void testWhileLoop() throws Throwable {
219 // int i = 0; while (i < limit) { ++i; } return i; => limit
220 MethodHandle loop = MethodHandles.whileLoop(While.MH_zero, While.MH_pred, While.MH_step);
221 assertEquals(While.MT_while, loop.type());
222 assertEquals(23, loop.invoke(23));
223 }
224
225 @Test
226 public static void testWhileLoopNoIteration() throws Throwable {
227 // a while loop that never executes its body because the predicate evaluates to false immediately
228 MethodHandle loop = MethodHandles.whileLoop(While.MH_initString, While.MH_predString, While.MH_stepString);
229 assertEquals(While.MT_string, loop.type());
230 assertEquals("a", loop.invoke());
231 }
232
233 @Test
234 public static void testDoWhileLoop() throws Throwable {
235 // int i = 0; do { ++i; } while (i < limit); return i; => limit
236 MethodHandle loop = MethodHandles.doWhileLoop(While.MH_zero, While.MH_step, While.MH_pred);
237 assertEquals(While.MT_while, loop.type());
238 assertEquals(23, loop.invoke(23));
239 }
240
241 @Test
242 public static void testDoWhileNullInit() throws Throwable {
243 While w = new While();
244 int v = 5;
245 MethodHandle loop = MethodHandles.doWhileLoop(null, While.MH_voidBody.bindTo(w), While.MH_voidPred.bindTo(w));
246 assertEquals(While.MT_void, loop.type());
247 loop.invoke(v);
248 assertEquals(v, w.i);
249 }
250
251 @Test
252 public static void testWhileZip() throws Throwable {
253 MethodHandle loop = MethodHandles.doWhileLoop(While.MH_zipInitZip, While.MH_zipStep, While.MH_zipPred);
254 assertEquals(While.MT_zip, loop.type());
255 List<String> a = Arrays.asList("a", "b", "c", "d");
256 List<String> b = Arrays.asList("e", "f", "g", "h");
257 List<String> zipped = Arrays.asList("a", "e", "b", "f", "c", "g", "d", "h");
258 assertEquals(zipped, (List<String>) loop.invoke(a.iterator(), b.iterator()));
259 }
260
261 @Test
262 public static void testWhileNullInit() throws Throwable {
263 While w = new While();
264 int v = 5;
265 MethodHandle loop = MethodHandles.whileLoop(null, While.MH_voidPred.bindTo(w), While.MH_voidBody.bindTo(w));
266 assertEquals(While.MT_void, loop.type());
267 loop.invoke(v);
268 assertEquals(v, w.i);
269 }
270
271 @Test
272 public static void testWhileVoidInit() throws Throwable {
273 While w = new While();
274 int v = 5;
275 MethodHandle loop = MethodHandles.whileLoop(While.MH_voidInit.bindTo(w), While.MH_voidPred.bindTo(w),
276 While.MH_voidBody.bindTo(w));
277 assertEquals(While.MT_void, loop.type());
278 loop.invoke(v);
279 assertEquals(v, w.i);
280 }
281
282 @Test
283 public static void testDoWhileVoidInit() throws Throwable {
284 While w = new While();
285 int v = 5;
286 MethodHandle loop = MethodHandles.doWhileLoop(While.MH_voidInit.bindTo(w), While.MH_voidBody.bindTo(w),
287 While.MH_voidPred.bindTo(w));
288 assertEquals(While.MT_void, loop.type());
289 loop.invoke(v);
290 assertEquals(v, w.i);
291 }
292
293 @Test
294 public static void testCountedLoop() throws Throwable {
295 // String s = "Lambdaman!"; for (int i = 0; i < 13; ++i) { s = "na " + s; } return s; => a variation on a well known theme
296 MethodHandle fit13 = MethodHandles.constant(int.class, 13);
297 MethodHandle loop = MethodHandles.countedLoop(fit13, Counted.MH_start, Counted.MH_step);
298 assertEquals(Counted.MT_counted, loop.type());
299 assertEquals("na na na na na na na na na na na na na Lambdaman!", loop.invoke("Lambdaman!"));
300 }
301
302 @Test
303 public static void testCountedLoopVoidInit() throws Throwable {
304 MethodHandle fit5 = MethodHandles.constant(int.class, 5);
305 MethodHandle loop = MethodHandles.countedLoop(fit5, MethodHandles.zero(void.class), Counted.MH_printHello);
306 assertEquals(Counted.MT_countedPrinting, loop.type());
307 loop.invoke();
308 }
309
310 @Test
311 public static void testCountedArrayLoop() throws Throwable {
312 // int[] a = new int[]{0}; for (int i = 0; i < 13; ++i) { ++a[0]; } => a[0] == 13
313 MethodHandle fit13 = MethodHandles.dropArguments(MethodHandles.constant(int.class, 13), 0, int[].class);
314 MethodHandle loop = MethodHandles.countedLoop(fit13, null, Counted.MH_stepUpdateArray);
315 assertEquals(Counted.MT_arrayCounted, loop.type());
316 int[] a = new int[]{0};
317 loop.invoke(a);
318 assertEquals(13, a[0]);
319 }
320
321 @Test
322 public static void testCountedPrintingLoop() throws Throwable {
323 MethodHandle fit5 = MethodHandles.constant(int.class, 5);
324 MethodHandle loop = MethodHandles.countedLoop(fit5, null, Counted.MH_printHello);
325 assertEquals(Counted.MT_countedPrinting, loop.type());
326 loop.invoke();
327 }
328
329 @Test
330 public static void testCountedRangeLoop() throws Throwable {
331 // String s = "Lambdaman!"; for (int i = -5; i < 8; ++i) { s = "na " + s; } return s; => a well known theme
332 MethodHandle fitm5 = MethodHandles.dropArguments(Counted.MH_m5, 0, String.class);
333 MethodHandle fit8 = MethodHandles.dropArguments(Counted.MH_8, 0, String.class);
334 MethodHandle loop = MethodHandles.countedLoop(fitm5, fit8, Counted.MH_start, Counted.MH_step);
335 assertEquals(Counted.MT_counted, loop.type());
336 assertEquals("na na na na na na na na na na na na na Lambdaman!", loop.invoke("Lambdaman!"));
337 }
338
339 @Test
340 public static void testCountedLoopCounterInit() throws Throwable {
341 // int x = 0; for (int i = 0; i < 5; ++i) { x += i; } return x; => 10
342 // (only if counter's first value in body is 0)
343 MethodHandle iter = MethodHandles.constant(int.class, 5);
344 MethodHandle init = MethodHandles.constant(int.class, 0);
345 MethodHandle body = Counted.MH_addCounter;
346 MethodHandle loop = MethodHandles.countedLoop(iter, init, body);
347 assertEquals(Counted.MT_counterInit, loop.type());
348 assertEquals(10, loop.invoke());
349 }
350
351 @Test
352 public static void testCountedLoopEmpty() throws Throwable {
353 // for (int i = 0; i < 5; ++i) { /* empty */ }
354 MethodHandle loop = MethodHandles.countedLoop(MethodHandles.constant(int.class, 5), null, null);
355 assertEquals(methodType(void.class), loop.type());
356 loop.invoke();
357 }
358
359 @Test
360 public static void testCountedRangeLoopEmpty() throws Throwable {
361 // for (int i = -5; i < 5; ++i) { /* empty */ }
362 MethodHandle loop = MethodHandles.countedLoop(MethodHandles.constant(int.class, -5),
363 MethodHandles.constant(int.class, 5), null, null);
364 assertEquals(methodType(void.class), loop.type());
365 loop.invoke();
366 }
367
368 @Test
369 public static void testIterateSum() throws Throwable {
370 // Integer[] a = new Integer[]{1,2,3,4,5,6}; int sum = 0; for (int e : a) { sum += e; } return sum; => 21
371 MethodHandle loop = MethodHandles.iteratedLoop(Iterate.MH_sumIterator, Iterate.MH_sumInit, Iterate.MH_sumStep);
372 assertEquals(Iterate.MT_sum, loop.type());
373 assertEquals(21, loop.invoke(new Integer[]{1, 2, 3, 4, 5, 6}));
374 }
375
376 @Test
377 public static void testIterateReverse() throws Throwable {
378 MethodHandle loop = MethodHandles.iteratedLoop(null, Iterate.MH_reverseInit, Iterate.MH_reverseStep);
379 assertEquals(Iterate.MT_reverse, loop.type());
380 List<String> list = Arrays.asList("a", "b", "c", "d", "e");
381 List<String> reversedList = Arrays.asList("e", "d", "c", "b", "a");
382 assertEquals(reversedList, (List<String>) loop.invoke(list));
383 }
384
385 @Test
386 public static void testIterateLength() throws Throwable {
387 MethodHandle loop = MethodHandles.iteratedLoop(null, Iterate.MH_lengthInit, Iterate.MH_lengthStep);
388 assertEquals(Iterate.MT_length, loop.type());
389 List<Double> list = Arrays.asList(23.0, 148.0, 42.0);
390 assertEquals(list.size(), (int) loop.invoke(list));
391 }
392
393 @Test
394 public static void testIterateMap() throws Throwable {
395 MethodHandle loop = MethodHandles.iteratedLoop(null, Iterate.MH_mapInit, Iterate.MH_mapStep);
396 assertEquals(Iterate.MT_map, loop.type());
397 List<String> list = Arrays.asList("Hello", "world", "!");
398 List<String> upList = Arrays.asList("HELLO", "WORLD", "!");
399 assertEquals(upList, (List<String>) loop.invoke(list));
400 }
401
402 @Test
403 public static void testIteratePrint() throws Throwable {
404 MethodHandle loop = MethodHandles.iteratedLoop(null, null, Iterate.MH_printStep);
405 assertEquals(Iterate.MT_print, loop.type());
406 loop.invoke(Arrays.asList("hello", "world"));
407 }
408
409 @Test
410 public static void testIterateNullBody() {
411 boolean caught = false;
412 try {
413 MethodHandles.iteratedLoop(MethodHandles.empty(methodType(Iterator.class, int.class)),
414 MethodHandles.identity(int.class), null);
415 } catch (IllegalArgumentException iae) {
416 assertEquals("iterated loop body must not be null", iae.getMessage());
417 caught = true;
418 }
419 assertTrue(caught);
420 }
421
422 @DataProvider
423 static Object[][] wrongIteratorTypes() {
424 return new Object[][]{{void.class}, {Object.class}, {Iterable.class}};
425 }
426
427 @Test(dataProvider = "wrongIteratorTypes")
428 public static void testIterateVoidIterator(Class<?> it) {
429 boolean caught = false;
430 MethodType v = methodType(it);
431 try {
432 MethodHandles.iteratedLoop(MethodHandles.empty(v), null, MethodHandles.empty(v));
433 } catch(IllegalArgumentException iae) {
434 assertEquals("iteratedLoop first argument must have Iterator return type", iae.getMessage());
435 caught = true;
436 }
437 assertTrue(caught);
438 }
439
440 @Test
441 public static void testIterateVoidInit() throws Throwable {
442 MethodHandle loop = MethodHandles.iteratedLoop(null, Iterate.MH_voidInit, Iterate.MH_printStep);
443 assertEquals(Iterate.MT_print, loop.type());
444 loop.invoke(Arrays.asList("hello", "world"));
445 }
446
447 @DataProvider
448 static Object[][] iterateParameters() {
449 MethodType i = methodType(int.class);
450 MethodType sil_i = methodType(int.class, String.class, int.class, List.class);
451 MethodType sl_v = methodType(void.class, String.class, List.class);
452 MethodType l_it = methodType(Iterator.class, List.class);
453 MethodType li_it = methodType(Iterator.class, List.class, int.class);
454 MethodType l_i = methodType(int.class, List.class);
455 MethodType _it = methodType(Iterator.class);
456 MethodType si_i = methodType(int.class, String.class, int.class);
457 MethodType s_i = methodType(int.class, String.class);
458 return new Object[][]{
459 {null, null, sl_v},
460 {null, i, sil_i},
461 {null, l_i, sil_i},
462 {l_it, null, sl_v},
463 {l_it, i, sil_i},
464 {li_it, l_i, sil_i},
465 {l_it, null, sil_i},
466 {li_it, null, sl_v},
467 {_it, l_i, si_i},
468 {_it, l_i, s_i}
469 };
470 }
471
472 @Test(dataProvider = "iterateParameters")
473 public static void testIterateParameters(MethodType it, MethodType in, MethodType bo) throws Throwable {
474 MethodHandle iterator = it == null ? null : MethodHandles.empty(it);
475 MethodHandle init = in == null ? null : MethodHandles.empty(in);
476 MethodHandle loop = MethodHandles.iteratedLoop(iterator, init, MethodHandles.empty(bo));
477 MethodType lt = loop.type();
478 if (it == null && in == null) {
479 assertEquals(bo.dropParameterTypes(0, 1), lt);
480 } else if (it == null) {
481 if (in.parameterCount() == 0) {
482 assertEquals(bo.dropParameterTypes(0, in.returnType() == void.class ? 1 : 2), lt);
483 } else {
484 assertEquals(methodType(bo.returnType(), in.parameterArray()), lt);
485 }
486 } else if (in == null) {
487 assertEquals(methodType(bo.returnType(), it.parameterArray()), lt);
488 } else if (it.parameterCount() > in.parameterCount()) {
489 assertEquals(methodType(bo.returnType(), it.parameterArray()), lt);
490 } else if (it.parameterCount() < in.parameterCount()) {
491 assertEquals(methodType(bo.returnType(), in.parameterArray()), lt);
492 } else {
493 // both it, in present; with equal parameter list lengths
494 assertEquals(it.parameterList(), lt.parameterList());
495 assertEquals(in.parameterList(), lt.parameterList());
496 assertEquals(bo.returnType(), lt.returnType());
497 }
498 }
499
500 @Test
501 public static void testIteratorSubclass() throws Throwable {
502 MethodHandle loop = MethodHandles.iteratedLoop(MethodHandles.empty(methodType(BogusIterator.class, List.class)),
503 null, MethodHandles.empty(methodType(void.class, String.class)));
504 assertEquals(methodType(void.class, List.class), loop.type());
505 }
506
507 static class BogusIterator implements Iterator {
508 @Override
509 public boolean hasNext() {
510 return false;
511 }
512 @Override
513 public Object next() {
514 return null;
515 }
516 }
517
518 static class Empty {
519
520 static void f() { }
521
522 static boolean pred() {
523 return false;
524 }
525
526 static int c() {
527 return 23;
528 }
529
530 static final Class<Empty> EMPTY = Empty.class;
531
532 static final MethodType MT_f = methodType(void.class);
533 static final MethodType MT_pred = methodType(boolean.class);
534 static final MethodType MT_c = methodType(int.class);
535
536 static final MethodHandle MH_f;
537 static final MethodHandle MH_pred;
538 static final MethodHandle MH_c;
539
540 static {
541 try {
542 MH_f = LOOKUP.findStatic(EMPTY, "f", MT_f);
543 MH_pred = LOOKUP.findStatic(EMPTY, "pred", MT_pred);
544 MH_c = LOOKUP.findStatic(EMPTY, "c", MT_c);
545 } catch (Exception e) {
546 throw new ExceptionInInitializerError(e);
547 }
548 }
549 }
550
551 static class Fac {
552
553 static int zero(int k) {
554 return 0;
555 }
556
557 static int one(int k) {
558 return 1;
559 }
560
561 static boolean pred(int i, int acc, int k) {
562 return i < k;
563 }
564
565 static int inc(int i, int acc, int k) {
566 return i + 1;
567 }
568
569 static int mult(int i, int acc, int k) {
570 return i * acc;
571 }
572
573 static void dot(int i, int acc, int k) {
574 System.out.print('.');
575 }
576
577 static int fin(int i, int acc, int k) {
578 return acc;
579 }
580
581 static final Class<Fac> FAC = Fac.class;
582
583 static final MethodType MT_init = methodType(int.class, int.class);
584 static final MethodType MT_fn = methodType(int.class, int.class, int.class, int.class);
585 static final MethodType MT_dot = methodType(void.class, int.class, int.class, int.class);
586 static final MethodType MT_pred = methodType(boolean.class, int.class, int.class, int.class);
587
588 static final MethodHandle MH_zero;
589 static final MethodHandle MH_one;
590 static final MethodHandle MH_pred;
591 static final MethodHandle MH_inc;
592 static final MethodHandle MH_mult;
593 static final MethodHandle MH_dot;
594 static final MethodHandle MH_fin;
595
596 static final MethodType MT_fac = methodType(int.class, int.class);
597
598 static {
599 try {
600 MH_zero = LOOKUP.findStatic(FAC, "zero", MT_init);
601 MH_one = LOOKUP.findStatic(FAC, "one", MT_init);
602 MH_pred = LOOKUP.findStatic(FAC, "pred", MT_pred);
603 MH_inc = LOOKUP.findStatic(FAC, "inc", MT_fn);
604 MH_mult = LOOKUP.findStatic(FAC, "mult", MT_fn);
605 MH_dot = LOOKUP.findStatic(FAC, "dot", MT_dot);
606 MH_fin = LOOKUP.findStatic(FAC, "fin", MT_fn);
607 } catch (Exception e) {
608 throw new ExceptionInInitializerError(e);
609 }
610 }
611
612 }
613
614 static class Loop {
615
616 static int inc(int i, int k) {
617 return i + 1;
618 }
619
620 static boolean pred(int i, int k) {
621 return i < k;
622 }
623
624 static int fin(int i, int k) {
625 return k;
626 }
627
628 static final Class<Loop> LOOP = Loop.class;
629
630 static final MethodType MT_inc = methodType(int.class, int.class, int.class);
631 static final MethodType MT_pred = methodType(boolean.class, int.class, int.class);
632 static final MethodType MT_fin = methodType(int.class, int.class, int.class);
633
634 static final MethodHandle MH_inc;
635 static final MethodHandle MH_pred;
636 static final MethodHandle MH_fin;
637
638 static final MethodType MT_loop = methodType(int.class, int.class);
639
640 static {
641 try {
642 MH_inc = LOOKUP.findStatic(LOOP, "inc", MT_inc);
643 MH_pred = LOOKUP.findStatic(LOOP, "pred", MT_pred);
644 MH_fin = LOOKUP.findStatic(LOOP, "fin", MT_fin);
645 } catch (Exception e) {
646 throw new ExceptionInInitializerError(e);
647 }
648 }
649
650 }
651
652 static class LoopWithVirtuals {
653
654 static int one(int k) {
655 return 1;
656 }
657
658 int inc(int i, int acc, int k) {
659 return i + 1;
660 }
661
662 int mult(int i, int acc, int k) {
663 return i * acc;
664 }
665
666 boolean pred(int i, int acc, int k) {
667 return i < k;
668 }
669
670 int fin(int i, int acc, int k) {
671 return acc;
672 }
673
674 static final Class<LoopWithVirtuals> LOOP_WITH_VIRTUALS = LoopWithVirtuals.class;
675
676 static final MethodType MT_one = methodType(int.class, int.class);
677 static final MethodType MT_inc = methodType(int.class, int.class, int.class, int.class);
678 static final MethodType MT_mult = methodType(int.class, int.class, int.class, int.class);
679 static final MethodType MT_pred = methodType(boolean.class, int.class, int.class, int.class);
680 static final MethodType MT_fin = methodType(int.class, int.class, int.class, int.class);
681
682 static final MethodHandle MH_one;
683 static final MethodHandle MH_inc;
684 static final MethodHandle MH_mult;
685 static final MethodHandle MH_pred;
686 static final MethodHandle MH_fin;
687
688 static final MethodType MT_loop = methodType(int.class, LOOP_WITH_VIRTUALS, int.class);
689
690 static {
691 try {
692 MH_one = LOOKUP.findStatic(LOOP_WITH_VIRTUALS, "one", MT_one);
693 MH_inc = LOOKUP.findVirtual(LOOP_WITH_VIRTUALS, "inc", MT_inc);
694 MH_mult = LOOKUP.findVirtual(LOOP_WITH_VIRTUALS, "mult", MT_mult);
695 MH_pred = LOOKUP.findVirtual(LOOP_WITH_VIRTUALS, "pred", MT_pred);
696 MH_fin = LOOKUP.findVirtual(LOOP_WITH_VIRTUALS, "fin", MT_fin);
697 } catch (Exception e) {
698 throw new ExceptionInInitializerError(e);
699 }
700 }
701
702 static MethodHandle permute(MethodHandle h) {
703 // The handles representing virtual methods need to be rearranged to match the required order of arguments
704 // (loop-local state comes first, then loop arguments). As the receiver comes first in the signature but is
705 // a loop argument, it must be moved to the appropriate position in the signature.
706 return MethodHandles.permuteArguments(h,
707 methodType(h.type().returnType(), int.class, int.class, LOOP_WITH_VIRTUALS, int.class), 2, 0, 1, 3);
708 }
709
710 }
711
712 static class While {
713
714 static int zero(int limit) {
715 return 0;
716 }
717
718 static boolean pred(int i, int limit) {
719 return i < limit;
720 }
721
722 static int step(int i, int limit) {
723 return i + 1;
724 }
725
726 static String initString() {
727 return "a";
728 }
729
730 static boolean predString(String s) {
731 return s.length() != 1;
732 }
733
734 static String stepString(String s) {
735 return s + "a";
736 }
737
738 static List<String> zipInitZip(Iterator<String> a, Iterator<String> b) {
739 return new ArrayList<>();
740 }
741
742 static boolean zipPred(List<String> zip, Iterator<String> a, Iterator<String> b) {
743 return a.hasNext() && b.hasNext();
744 }
745
746 static List<String> zipStep(List<String> zip, Iterator<String> a, Iterator<String> b) {
747 zip.add(a.next());
748 zip.add(b.next());
749 return zip;
750 }
751
752 private int i = 0;
753
754 void voidInit(int k) {
755 // empty
756 }
757
758 void voidBody(int k) {
759 ++i;
760 }
761
762 boolean voidPred(int k) {
763 return i < k;
764 }
765
766 static final Class<While> WHILE = While.class;
767
768 static final MethodType MT_zero = methodType(int.class, int.class);
769 static final MethodType MT_pred = methodType(boolean.class, int.class, int.class);
770 static final MethodType MT_fn = methodType(int.class, int.class, int.class);
771 static final MethodType MT_initString = methodType(String.class);
772 static final MethodType MT_predString = methodType(boolean.class, String.class);
773 static final MethodType MT_stepString = methodType(String.class, String.class);
774 static final MethodType MT_zipInitZip = methodType(List.class, Iterator.class, Iterator.class);
775 static final MethodType MT_zipPred = methodType(boolean.class, List.class, Iterator.class, Iterator.class);
776 static final MethodType MT_zipStep = methodType(List.class, List.class, Iterator.class, Iterator.class);
777 static final MethodType MT_voidInit = methodType(void.class, int.class);
778 static final MethodType MT_voidBody = methodType(void.class, int.class);
779 static final MethodType MT_voidPred = methodType(boolean.class, int.class);
780
781 static final MethodHandle MH_zero;
782 static final MethodHandle MH_pred;
783 static final MethodHandle MH_step;
784 static final MethodHandle MH_initString;
785 static final MethodHandle MH_predString;
786 static final MethodHandle MH_stepString;
787 static final MethodHandle MH_zipInitZip;
788 static final MethodHandle MH_zipPred;
789 static final MethodHandle MH_zipStep;
790 static final MethodHandle MH_voidInit;
791 static final MethodHandle MH_voidBody;
792 static final MethodHandle MH_voidPred;
793
794 static final MethodType MT_while = methodType(int.class, int.class);
795 static final MethodType MT_string = methodType(String.class);
796 static final MethodType MT_zip = methodType(List.class, Iterator.class, Iterator.class);
797 static final MethodType MT_void = methodType(void.class, int.class);
798
799 static {
800 try {
801 MH_zero = LOOKUP.findStatic(WHILE, "zero", MT_zero);
802 MH_pred = LOOKUP.findStatic(WHILE, "pred", MT_pred);
803 MH_step = LOOKUP.findStatic(WHILE, "step", MT_fn);
804 MH_initString = LOOKUP.findStatic(WHILE, "initString", MT_initString);
805 MH_predString = LOOKUP.findStatic(WHILE, "predString", MT_predString);
806 MH_stepString = LOOKUP.findStatic(WHILE, "stepString", MT_stepString);
807 MH_zipInitZip = LOOKUP.findStatic(WHILE, "zipInitZip", MT_zipInitZip);
808 MH_zipPred = LOOKUP.findStatic(WHILE, "zipPred", MT_zipPred);
809 MH_zipStep = LOOKUP.findStatic(WHILE, "zipStep", MT_zipStep);
810 MH_voidInit = LOOKUP.findVirtual(WHILE, "voidInit", MT_voidInit);
811 MH_voidBody = LOOKUP.findVirtual(WHILE, "voidBody", MT_voidBody);
812 MH_voidPred = LOOKUP.findVirtual(WHILE, "voidPred", MT_voidPred);
813 } catch (Exception e) {
814 throw new ExceptionInInitializerError(e);
815 }
816 }
817
818 }
819
820 static class Counted {
821
822 static String start(String arg) {
823 return arg;
824 }
825
826 static String step(int counter, String v, String arg) {
827 return "na " + v;
828 }
829
830 static void stepUpdateArray(int counter, int[] a) {
831 ++a[0];
832 }
833
834 static void printHello(int counter) {
835 System.out.print("hello");
836 }
837
838 static int addCounter(int counter, int x) {
839 return x + counter;
840 }
841
842 static final Class<Counted> COUNTED = Counted.class;
843
844 static final MethodType MT_start = methodType(String.class, String.class);
845 static final MethodType MT_step = methodType(String.class, int.class, String.class, String.class);
846 static final MethodType MT_stepUpdateArray = methodType(void.class, int.class, int[].class);
847 static final MethodType MT_printHello = methodType(void.class, int.class);
848 static final MethodType MT_addCounter = methodType(int.class, int.class, int.class);
849
850 static final MethodHandle MH_13;
851 static final MethodHandle MH_m5;
852 static final MethodHandle MH_8;
853 static final MethodHandle MH_start;
854 static final MethodHandle MH_step;
855 static final MethodHandle MH_stepUpdateArray;
856 static final MethodHandle MH_printHello;
857 static final MethodHandle MH_addCounter;
858
859 static final MethodType MT_counted = methodType(String.class, String.class);
860 static final MethodType MT_arrayCounted = methodType(void.class, int[].class);
861 static final MethodType MT_countedPrinting = methodType(void.class);
862 static final MethodType MT_counterInit = methodType(int.class);
863
864 static {
865 try {
866 MH_13 = MethodHandles.constant(int.class, 13);
867 MH_m5 = MethodHandles.constant(int.class, -5);
868 MH_8 = MethodHandles.constant(int.class, 8);
869 MH_start = LOOKUP.findStatic(COUNTED, "start", MT_start);
870 MH_step = LOOKUP.findStatic(COUNTED, "step", MT_step);
871 MH_stepUpdateArray = LOOKUP.findStatic(COUNTED, "stepUpdateArray", MT_stepUpdateArray);
872 MH_printHello = LOOKUP.findStatic(COUNTED, "printHello", MT_printHello);
873 MH_addCounter = LOOKUP.findStatic(COUNTED, "addCounter", MT_addCounter);
874 } catch (Exception e) {
875 throw new ExceptionInInitializerError(e);
876 }
877 }
878
879 }
880
881 static class Iterate {
882
883 static Iterator<Integer> sumIterator(Integer[] a) {
884 return Arrays.asList(a).iterator();
885 }
886
887 static int sumInit(Integer[] a) {
888 return 0;
889 }
890
891 static int sumStep(int s, int e, Integer[] a) {
892 return s + e;
893 }
894
895 static List<String> reverseInit(List<String> l) {
896 return new ArrayList<>();
897 }
898
899 static List<String> reverseStep(String e, List<String> r, List<String> l) {
900 r.add(0, e);
901 return r;
902 }
903
904 static int lengthInit(List<Double> l) {
905 return 0;
906 }
907
908 static int lengthStep(Object o, int len, List<Double> l) {
909 return len + 1;
910 }
911
912 static List<String> mapInit(List<String> l) {
913 return new ArrayList<>();
914 }
915
916 static List<String> mapStep(String e, List<String> r, List<String> l) {
917 r.add(e.toUpperCase());
918 return r;
919 }
920
921 static void printStep(String s, List<String> l) {
922 System.out.print(s);
923 }
924
925 static void voidInit() {
926 // empty
927 }
928
929 static final Class<Iterate> ITERATE = Iterate.class;
930
931 static final MethodType MT_sumIterator = methodType(Iterator.class, Integer[].class);
932
933 static final MethodType MT_sumInit = methodType(int.class, Integer[].class);
934 static final MethodType MT_reverseInit = methodType(List.class, List.class);
935 static final MethodType MT_lenghInit = methodType(int.class, List.class);
936 static final MethodType MT_mapInit = methodType(List.class, List.class);
937
938 static final MethodType MT_sumStep = methodType(int.class, int.class, int.class, Integer[].class);
939 static final MethodType MT_reverseStep = methodType(List.class, String.class, List.class, List.class);
940 static final MethodType MT_lengthStep = methodType(int.class, Object.class, int.class, List.class);
941 static final MethodType MT_mapStep = methodType(List.class, String.class, List.class, List.class);
942 static final MethodType MT_printStep = methodType(void.class, String.class, List.class);
943
944 static final MethodType MT_voidInit = methodType(void.class);
945
946 static final MethodHandle MH_sumIterator;
947 static final MethodHandle MH_sumInit;
948 static final MethodHandle MH_sumStep;
949 static final MethodHandle MH_printStep;
950
951 static final MethodHandle MH_reverseInit;
952 static final MethodHandle MH_reverseStep;
953
954 static final MethodHandle MH_lengthInit;
955 static final MethodHandle MH_lengthStep;
956
957 static final MethodHandle MH_mapInit;
958 static final MethodHandle MH_mapStep;
959
960 static final MethodHandle MH_voidInit;
961
962 static final MethodType MT_sum = methodType(int.class, Integer[].class);
963 static final MethodType MT_reverse = methodType(List.class, List.class);
964 static final MethodType MT_length = methodType(int.class, List.class);
965 static final MethodType MT_map = methodType(List.class, List.class);
966 static final MethodType MT_print = methodType(void.class, List.class);
967
968 static {
969 try {
970 MH_sumIterator = LOOKUP.findStatic(ITERATE, "sumIterator", MT_sumIterator);
971 MH_sumInit = LOOKUP.findStatic(ITERATE, "sumInit", MT_sumInit);
972 MH_sumStep = LOOKUP.findStatic(ITERATE, "sumStep", MT_sumStep);
973 MH_reverseInit = LOOKUP.findStatic(ITERATE, "reverseInit", MT_reverseInit);
974 MH_reverseStep = LOOKUP.findStatic(ITERATE, "reverseStep", MT_reverseStep);
975 MH_lengthInit = LOOKUP.findStatic(ITERATE, "lengthInit", MT_lenghInit);
976 MH_lengthStep = LOOKUP.findStatic(ITERATE, "lengthStep", MT_lengthStep);
977 MH_mapInit = LOOKUP.findStatic(ITERATE, "mapInit", MT_mapInit);
978 MH_mapStep = LOOKUP.findStatic(ITERATE, "mapStep", MT_mapStep);
979 MH_printStep = LOOKUP.findStatic(ITERATE, "printStep", MT_printStep);
980 MH_voidInit = LOOKUP.findStatic(ITERATE, "voidInit", MT_voidInit);
981 } catch (Exception e) {
982 throw new ExceptionInInitializerError(e);
983 }
984 }
985
986 }
987
988 }