1 /*
  2  * Copyright (c) 2022, 2025, 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.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  */
 23 /*
 24  * @test
 25  * @bug 8194743 8345438 8356551 8349754 8379833
 26  * @library /tools/javac/lib
 27  * @summary Test valid placements of super()/this() in constructors
 28  * @modules jdk.compiler/com.sun.tools.javac.tree
 29  *          jdk.compiler/com.sun.tools.javac.util
 30  * @enablePreview
 31  * @run main SuperInitGood
 32  */
 33 
 34 import java.util.concurrent.atomic.AtomicReference;
 35 
 36 public class SuperInitGood {
 37 
 38     SuperInitGood(Object obj) {
 39     }
 40 
 41     SuperInitGood(int x) {
 42     }
 43 
 44     // Default constructor provided by compiler
 45     static class Test0 {
 46     }
 47 
 48     // No explicit calls to this()/super()
 49     static class Test1 {
 50         Test1() {
 51         }
 52 
 53         Test1(int a) {
 54             this.hashCode();
 55         }
 56     }
 57 
 58     // Explicit calls to this()/super()
 59     static class Test2<T> {
 60         static int i;
 61         Test2() {
 62             this(0);
 63         }
 64         Test2(int i) {
 65             Test2.i = i;
 66             super();
 67         }
 68         Test2(T obj) {
 69             this(java.util.Objects.hashCode(obj));
 70         }
 71         public T get() {
 72             return null;
 73         }
 74     }
 75 
 76     // Explicit this()/super() with stuff in front
 77     static class Test3 {
 78         int x;
 79         final int y;
 80         final int z;
 81 
 82         Test3() {
 83             new Object().hashCode();
 84             new Object().hashCode();
 85             super();
 86             this.x = new Object().hashCode();
 87             this.y = new Object().hashCode() % 17;
 88             this.z = this.x + this.y;
 89         }
 90     }
 91 
 92     // Reference within constructor to outer class that's also my superclass
 93     class Test5 extends SuperInitGood {
 94         Test5(Object obj) {
 95             if (obj == null)
 96                 throw new IllegalArgumentException();
 97             super(SuperInitGood.this);      // NOT a 'this' reference
 98         }
 99     }
100 
101     // Initialization blocks
102     class Test6 {
103         final long startTime;
104         final int x;
105         {
106             this.x = 12;
107         }
108         Test6() {
109             long now = System.nanoTime();
110             long then = now + 1000000L;
111             while (System.nanoTime() < then) {
112                 try {
113                     Thread.sleep(1);
114                 } catch (InterruptedException e) {
115                     Thread.currentThread().interrupt();
116                     break;
117                 }
118             }
119             super();
120             this.startTime = now;
121         }
122     }
123 
124     // Mix up inner classes, proxies, and super() calls
125     // Copied mostly from UnverifiableInitForNestedLocalClassTest.java
126     public static void test7(final String arg) {
127         final String inlined = " inlined ";
128         class LocalClass {
129             String m() {
130                 return "LocalClass " + arg + inlined;
131             }
132 
133             class SubClass extends LocalClass {
134                 @Override
135                 String m() {
136                     return "SubClass " + arg + inlined;
137                 }
138             }
139 
140             class SubSubClass extends SubClass {
141                 @Override
142                 String m() {
143                     return "SubSubClass " + arg + inlined;
144                 }
145             }
146 
147             class AnotherLocal {
148                 class AnotherSub extends LocalClass {
149                     AnotherSub() {
150                     }
151                     AnotherSub(int x) {
152                         this((char)x);
153                     }
154                     AnotherSub(char y) {
155                         super();
156                     }
157                     @Override
158                     String m() {
159                         return "AnotherSub " + arg + inlined;
160                     }
161                 }
162             }
163         }
164     }
165 
166     // Anonymous inner class
167     public static void test8() {
168         new Test2<Byte>(null) {
169             @Override
170             public Byte get() {
171                 return (byte)-1;
172             }
173         };
174     }
175 
176     // Qualified super() invocation
177     public static class Test9 extends Test5 {
178 
179         public Test9(SuperInitGood implicit, Object obj) {
180             obj.hashCode();
181             implicit.super(obj);
182         }
183     }
184 
185     // Copied from WhichImplicitThis6
186     public static class Test10 {
187         private int i;
188         public Test10(int i) {}
189         public class Sub extends Test10 {
190             public Sub() {
191                 super(i); // i is not inherited, so it is the enclosing i
192             }
193         }
194     }
195 
196     // Two constructors where only one invokes super()
197     public static class Test11 {
198         public Test11() {
199         }
200         public Test11(int x) {
201             super();
202         }
203     }
204 
205     // Nested version of the previous test
206     public static class Test12 {
207         Test12() {
208             class Sub {
209                 public Sub() {
210                 }
211                 public Sub(int j) {
212                     super();
213                 }
214             }
215         }
216     }
217 
218     // Nested super()'s requiring initialization code appended
219     public static class Test13 extends SuperInitGood {
220         final int x = new Object().hashCode();
221         Test13() {
222             super(new Object() {
223                 public void foo() {
224                     class Bar {
225                         final int y = new Object().hashCode();
226                         Bar() {
227                             super();
228                         }
229                         Bar(int ignored) {
230                         }
231                     }
232                 }
233             });
234         }
235     }
236 
237     // Initializer in initializer block
238     public static class Test14 {
239         final int x;                // initialized in constructor
240         final int y;                // initialized in initialization block
241         final int z = 13;           // initialized with intializer value
242         public Test14() {
243             this(0);
244         }
245         public Test14(boolean z) {
246             this.x = z ? 1 : 0;
247         }
248         public Test14(int x) {
249             super();
250             this.x = x;
251         }
252         {
253             this.y = -1;
254         }
255     }
256 
257     // Qualified super() invocation with superclass instance
258     public static class Test15 {
259 
260         final String name;
261 
262         public Test15(String name) {
263             this.name = name;
264         }
265 
266         public class Test15b extends Test15 {
267 
268             public Test15b(String name) {
269                 super(name);
270             }
271 
272             public String getName() {
273                 return Test15.this.name;
274             }
275         }
276     }
277 
278     public static class Test15c extends Test15.Test15b {
279         public Test15c(Test15 a, String name) {
280             a.super(name);
281         }
282     }
283 
284     // Mixing up outer instances, proxies, and initializers
285     public static class Test16 {
286 
287         final String x = String.valueOf(new Object().hashCode());
288 
289         public void run() {
290 
291             final String y = String.valueOf(new Object().hashCode());
292 
293             class Sub {
294 
295                 final String z;
296 
297                 Sub(String z, int ignored) {
298                     this(z, (float)ignored);
299                 }
300 
301                 Sub(String z, float ignored) {
302                     this.z = z;
303                 }
304 
305                 Sub(String z, byte ignored) {
306                     super();
307                     this.z = z;
308                 }
309 
310                 Sub(String z, char ignored) {
311                     this(z, (int)ignored);
312                 }
313 
314                 String x() {
315                     return x;
316                 }
317 
318                 String y() {
319                     return y;
320                 }
321 
322                 String z() {
323                     return z;
324                 }
325             }
326 
327             final String z = String.valueOf(new Object().hashCode());
328 
329             final Sub[] subs = new Sub[] {
330                 new Sub(z, 1),
331                 new Sub(z, -1),
332                 new Sub(z, (float)0),
333                 new Sub(z, (byte)0),
334                 new Sub(z, (char)0)
335             };
336 
337             for (int i = 0; i < subs.length; i++) {
338                 //System.err.println("i = " + i);
339                 final Sub sub = subs[i];
340                 final String subx = sub.x();
341                 final String suby = sub.y();
342                 final String subz = sub.z();
343                 if (!x.equals(subx))
344                     throw new RuntimeException("x=" + x + " but sub[" + i + "].x()=" + subx);
345                 if (!y.equals(suby))
346                     throw new RuntimeException("y=" + y + " but sub[" + i + "].y()=" + suby);
347                 if (!z.equals(subz))
348                     throw new RuntimeException("z=" + z + " but sub[" + i + "].z()=" + subz);
349             }
350         }
351     }
352 
353     // Records
354     public class Test17 {
355 
356         record Rectangle(float length, float width) { }
357 
358         record StringHolder(String string) {
359             StringHolder {
360                 java.util.Objects.requireNonNull(string);
361             }
362         }
363 
364         record ValueHolder(int value) {
365             ValueHolder(float x) {
366                 if (Float.isNaN(x))
367                     throw new IllegalArgumentException();
368                 this((int)x);
369             }
370         }
371     }
372 
373     // Exceptions thrown by initializer block
374     public static class Test18 extends AtomicReference<Object> {
375 
376         {
377             if ((this.get().hashCode() % 3) == 0)
378                 throw new MyException();
379         }
380 
381         public Test18(Object obj) throws MyException {
382             super(obj);
383         }
384 
385         public Test18(boolean fail) throws MyException {
386             Object obj;
387             for (obj = new Object(); true; obj = new Object()) {
388                 if (((obj.hashCode() % 3) == 0) != fail)
389                     continue;
390                 break;
391             }
392             this(obj);
393         }
394 
395         public static class MyException extends Exception {
396         }
397     }
398 
399     // super()/this() within outer try block but inside inner class
400     public static class Test19 {
401         public Test19(int x) {
402             try {
403                 new Test1(x) {
404                     @Override
405                     public int hashCode() {
406                         return x ^ super.hashCode();
407                     }
408                 };
409             } catch (StackOverflowError e) {
410                 // ignore
411             }
412         }
413     }
414 
415     // we allow 'this' reference prior to super() for field assignments only
416     public static class Test20 {
417         private int x;
418         public Test20(short x) {
419             x = x;
420             super();
421         }
422         public Test20(int x) {
423             this.x = x;
424             super();
425         }
426         public Test20(char x) {
427             Test20.this.x = x;
428             super();
429         }
430     }
431 
432     // allow creating and using local and anonymous classes before super()
433     // they will not have enclosing instances though
434     public static class Test21 {
435         public Test21(int x) {
436             Runnable r = new Runnable() {
437                 public void run() {
438                     this.hashCode();
439                 }
440             };
441             r.run();
442             super();
443             r.run();
444         }
445         public Test21(float x) {
446             class Foo {
447                 public void bar() {
448                     this.hashCode();
449                 }
450             };
451             new Foo().bar();
452             super();
453             new Foo().bar();
454         }
455     }
456 
457     // Lambdas within constructors (JDK-8345438)
458     public static class Test22 {
459         public Test22() {
460             Runnable r = () -> System.out.println();
461             super();
462             r.run();
463         }
464         public Test22(int x) {
465             Runnable r = () -> System.out.println();
466             r.run();
467             super();
468         }
469         public Test22(char x) {
470             Runnable r = () -> {
471                 class A {
472                     A() {
473                         return;
474                     }
475                     A(int x) {
476                         Runnable r2 = () -> {
477                             return;
478                         };
479                         this();
480                         r2.run();
481                     }
482                     A(char x) {
483                         this(0);
484                     }
485                 }
486                 return;
487             };
488             r.run();
489             super();
490         }
491     }
492 
493     // Receiver parameter syntax (JDK-8356551)
494     public static class Test23 {
495         public Test23() {
496             class Local {
497                 Local(Test23 Test23.this) {
498                 }
499             }
500             super();
501             new Local();
502         }
503     }
504 
505     // Test for JDK-8349754
506     public static class Test24 {
507         private int i;
508         class Sub extends Test24 {
509             Sub() {
510                 i = 3;      // here "i" refers to "Test23.this.i", not "this.i" - so it's OK
511                 super();
512             }
513         }
514     }
515 
516     public static class Test25 {
517         public Test25(Object o) {}
518 
519         class Sub extends Test25 {
520             public Sub() {
521                 super(new Object() {
522                     void foo() {
523                         getClass();
524                     }
525                 });
526             }
527         }
528     }
529 
530     public static class Test26 {
531         Test26(Test26 t) {}
532 
533         Test26(String s) {
534             this(new Test26());
535         }
536 
537         Test26() {}
538 
539         public static void main(String[] args) {
540             new Test26("test");
541         }
542     }
543 
544     public static void main(String[] args) {
545         new Test0();
546         new Test1();
547         new Test1(7);
548         new Test2<Byte>();
549         new Test2<>(args);
550         new Test3();
551         new SuperInitGood(3).new Test5(3);
552         new SuperInitGood(3).new Test6();
553         SuperInitGood.test7("foo");
554         SuperInitGood.test8();
555         new Test9(new SuperInitGood(5), "abc");
556         new Test10(7);
557         new Test11(9);
558         new Test12();
559         new Test13();
560         Test14 t14 = new Test14();
561         assert t14.x == 0 && t14.y == -1 && t14.z == 13;
562         t14 = new Test14(7);
563         assert t14.x == 7 && t14.y == -1 && t14.z == 13;
564         new Test15c(new Test15("foo"), "bar");
565         new Test16().run();
566         new Test17.StringHolder("foo");
567         try {
568             new Test17.StringHolder(null);
569             throw new Error();
570         } catch (NullPointerException e) {
571             // expected
572         }
573         try {
574             new Test18(true);
575             assert false : "expected exception";
576         } catch (Test18.MyException e) {
577             // expected
578         }
579         try {
580             new Test18(false);
581         } catch (Test18.MyException e) {
582             assert false : "unexpected exception: " + e;
583         }
584         new Test19(123);
585         new Test20(123);
586         new Test21((int)123);
587         new Test21((float)123);
588         new Test22('x');
589         new Test23();
590         new Test24();
591         new Test25(null);
592         new Test26("");
593     }
594 }