1 /*

     2  * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.

     3  * Copyright (c) 2019 SAP SE. All rights reserved.

     4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     5  *

     6  * This code is free software; you can redistribute it and/or modify it

     7  * under the terms of the GNU General Public License version 2 only, as

     8  * published by the Free Software Foundation.

     9  *

    10  * This code is distributed in the hope that it will be useful, but WITHOUT

    11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    13  * version 2 for more details (a copy is included in the LICENSE file that

    14  * accompanied this code).

    15  *

    16  * You should have received a copy of the GNU General Public License version

    17  * 2 along with this work; if not, write to the Free Software Foundation,

    18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    19  *

    20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    21  * or visit www.oracle.com if you need additional information or have any

    22  * questions.

    23  */

    24 

    25 /**

    26  * @test

    27  * @summary Test extended NullPointerException message for

    28  *   classfiles generated with debug information. In this case the name

    29  *   of the variable containing the array is printed.

    30  * @bug 8218628

    31  * @modules java.base/java.lang:open

    32  *          java.base/jdk.internal.org.objectweb.asm

    33  * @library /test/lib

    34  * @compile -g NullPointerExceptionTest.java

    35  * @run main/othervm -XX:MaxJavaStackTraceDepth=1 -XX:+ShowCodeDetailsInExceptionMessages NullPointerExceptionTest hasDebugInfo

    36  */

    37 /**

    38  * @test

    39  * @summary Test extended NullPointerException message for class

    40  *   files generated without debugging information. The message lists

    41  *   detailed information about the entity that is null.

    42  * @bug 8218628

    43  * @modules java.base/java.lang:open

    44  *          java.base/jdk.internal.org.objectweb.asm

    45  * @library /test/lib

    46  * @compile NullPointerExceptionTest.java

    47  * @run main/othervm -XX:MaxJavaStackTraceDepth=1 -XX:+ShowCodeDetailsInExceptionMessages NullPointerExceptionTest

    48  */

    49 

    50 import java.io.ByteArrayInputStream;

    51 import java.io.ByteArrayOutputStream;

    52 import java.io.ObjectInputStream;

    53 import java.io.ObjectOutputStream;

    54 import java.lang.invoke.MethodHandles.Lookup;

    55 import java.util.ArrayList;

    56 

    57 import jdk.internal.org.objectweb.asm.ClassWriter;

    58 import jdk.internal.org.objectweb.asm.Label;

    59 import jdk.internal.org.objectweb.asm.MethodVisitor;

    60 import jdk.test.lib.Asserts;

    61 

    62 import static java.lang.invoke.MethodHandles.lookup;

    63 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_PUBLIC;

    64 import static jdk.internal.org.objectweb.asm.Opcodes.ACC_SUPER;

    65 import static jdk.internal.org.objectweb.asm.Opcodes.ACONST_NULL;

    66 import static jdk.internal.org.objectweb.asm.Opcodes.ALOAD;

    67 import static jdk.internal.org.objectweb.asm.Opcodes.ASTORE;

    68 import static jdk.internal.org.objectweb.asm.Opcodes.GETFIELD;

    69 import static jdk.internal.org.objectweb.asm.Opcodes.GETSTATIC;

    70 import static jdk.internal.org.objectweb.asm.Opcodes.ICONST_1;

    71 import static jdk.internal.org.objectweb.asm.Opcodes.ICONST_2;

    72 import static jdk.internal.org.objectweb.asm.Opcodes.INVOKESPECIAL;

    73 import static jdk.internal.org.objectweb.asm.Opcodes.INVOKEVIRTUAL;

    74 import static jdk.internal.org.objectweb.asm.Opcodes.ARETURN;

    75 import static jdk.internal.org.objectweb.asm.Opcodes.IRETURN;

    76 import static jdk.internal.org.objectweb.asm.Opcodes.RETURN;

    77 

    78 /**

    79  * Tests NullPointerExceptions

    80  */

    81 public class NullPointerExceptionTest {

    82 

    83     // Some fields used in the test.

    84     static Object nullStaticField;

    85     NullPointerExceptionTest nullInstanceField;

    86     static int[][][][] staticArray;

    87     static long[][] staticLongArray = new long[1000][];

    88     DoubleArrayGen dag;

    89     ArrayList<String> names = new ArrayList<>();

    90     ArrayList<String> curr;

    91     static boolean hasDebugInfo = false;

    92 

    93     static {

    94         staticArray       = new int[1][][][];

    95         staticArray[0]    = new int[1][][];

    96         staticArray[0][0] = new int[1][];

    97     }

    98 

    99     public static void checkMessage(Throwable t, String expression,

   100                                     String obtainedMsg, String expectedMsg) {

   101         System.out.println("\nSource code:\n  " + expression + "\n\nOutput:");

   102         t.printStackTrace(System.out);

   103         if (obtainedMsg != expectedMsg && // E.g. both are null.

   104             !obtainedMsg.equals(expectedMsg)) {

   105             System.out.println("expected msg: " + expectedMsg);

   106             Asserts.assertEquals(expectedMsg, obtainedMsg);

   107         }

   108         System.out.println("\n----");

   109     }

   110 

   111     public static void main(String[] args) throws Exception {

   112         NullPointerExceptionTest t = new NullPointerExceptionTest();

   113         if (args.length > 0) {

   114             hasDebugInfo = true;

   115         }

   116 

   117         System.out.println("Tests for the first part of the message:");

   118         System.out.println("========================================\n");

   119 

   120         // Test the message printed for the failed action.

   121         t.testFailedAction();

   122 

   123         System.out.println("Tests for the second part of the message:");

   124         System.out.println("=========================================\n");

   125         // Test the method printed for the null entity.

   126         t.testNullEntity();

   127 

   128         System.out.println("Further tests:");

   129         System.out.println("==============\n");

   130 

   131         // Test if parameters are used in the code.

   132         // This is relevant if there is no debug information.

   133         t.testParameters();

   134 

   135         // Test that no message is printed for exceptions

   136         // allocated explicitly.

   137         t.testCreation();

   138 

   139         // Test that no message is printed for exceptions

   140         // thrown in native methods.

   141         t.testNative();

   142 

   143         // Test that two calls to getMessage() return the same

   144         // message.

   145         // It is a design decision that it returns two different

   146         // String objects.

   147         t.testSameMessage();

   148 

   149         // Test serialization.

   150         // It is a design decision that after serialization the

   151         // the message is lost.

   152         t.testSerialization();

   153 

   154         // Test that messages are printed for code generated

   155         // on-the-fly.

   156         t.testGeneratedCode();

   157 

   158         // Some more interesting complex messages.

   159         t.testComplexMessages();

   160     }

   161 

   162     // Helper method to cause test case.

   163     private double callWithTypes(String[][] dummy1, int[][][] dummy2, float dummy3, long dummy4, short dummy5,

   164                                  boolean dummy6, byte dummy7, double dummy8, char dummy9) {

   165         return 0.0;

   166     }

   167 

   168     @SuppressWarnings("null")

   169     public void testFailedAction() {

   170         int[]     ia1 = null;

   171         float[]   fa1 = null;

   172         Object[]  oa1 = null;

   173         boolean[] za1 = null;

   174         byte[]    ba1 = null;

   175         char[]    ca1 = null;

   176         short[]   sa1 = null;

   177         long[]    la1 = null;

   178         double[]  da1 = null;

   179 

   180         // iaload

   181         try {

   182             int val = ia1[0];

   183             System.out.println(val);

   184             Asserts.fail();

   185         } catch (NullPointerException e) {

   186             checkMessage(e, "int val = ia1[0];", e.getMessage(),

   187                          "Cannot load from int array because " +

   188                          (hasDebugInfo ? "\"ia1\"" : "\"<local1>\"") + " is null");

   189         }

   190         // faload

   191         try {

   192             float val = fa1[0];

   193             System.out.println(val);

   194             Asserts.fail();

   195         } catch (NullPointerException e) {

   196             checkMessage(e, "float val = fa1[0];", e.getMessage(),

   197                          "Cannot load from float array because " +

   198                          (hasDebugInfo ? "\"fa1\"" : "\"<local2>\"") + " is null");

   199         }

   200         // aaload

   201         try {

   202             Object val = oa1[0];

   203             System.out.println(val);

   204             Asserts.fail();

   205         } catch (NullPointerException e) {

   206             checkMessage(e, "Object val = oa1[0];", e.getMessage(),

   207                          "Cannot load from object array because " +

   208                          (hasDebugInfo ? "\"oa1\"" : "\"<local3>\"") + " is null");

   209         }

   210         // baload (boolean)

   211         try {

   212             boolean val = za1[0];

   213             System.out.println(val);

   214             Asserts.fail();

   215         } catch (NullPointerException e) {

   216             checkMessage(e, "boolean val = za1[0];", e.getMessage(),

   217                          "Cannot load from byte/boolean array because " +

   218                          (hasDebugInfo ? "\"za1\"" : "\"<local4>\"") + " is null");

   219         }

   220         // baload (byte)

   221         try {

   222             byte val = ba1[0];

   223             System.out.println(val);

   224             Asserts.fail();

   225         } catch (NullPointerException e) {

   226             checkMessage(e, "byte val = ba1[0];", e.getMessage(),

   227                          "Cannot load from byte/boolean array because " +

   228                          (hasDebugInfo ? "\"ba1\"" : "\"<local5>\"") + " is null");

   229         }

   230         // caload

   231         try {

   232             char val = ca1[0];

   233             System.out.println(val);

   234             Asserts.fail();

   235         } catch (NullPointerException e) {

   236             checkMessage(e, "char val = ca1[0];", e.getMessage(),

   237                          "Cannot load from char array because " +

   238                          (hasDebugInfo ? "\"ca1\"" : "\"<local6>\"") + " is null");

   239         }

   240         // saload

   241         try {

   242             short val = sa1[0];

   243             System.out.println(val);

   244             Asserts.fail();

   245         } catch (NullPointerException e) {

   246             checkMessage(e, "short val = sa1[0];", e.getMessage(),

   247                          "Cannot load from short array because " +

   248                          (hasDebugInfo ? "\"sa1\"" : "\"<local7>\"") + " is null");

   249         }

   250         // laload

   251         try {

   252             long val = la1[0];

   253             System.out.println(val);

   254             Asserts.fail();

   255         } catch (NullPointerException e) {

   256             checkMessage(e, "long val = la1[0];", e.getMessage(),

   257                          "Cannot load from long array because " +

   258                          (hasDebugInfo ? "\"la1\"" : "\"<local8>\"") + " is null");

   259         }

   260         // daload

   261         try {

   262             double val = da1[0];

   263             System.out.println(val);

   264             Asserts.fail();

   265         } catch (NullPointerException e) {

   266             checkMessage(e, "double val = da1[0];", e.getMessage(),

   267                          "Cannot load from double array because " +

   268                          (hasDebugInfo ? "\"da1\"" : "\"<local9>\"") + " is null");

   269         }

   270 

   271         // iastore

   272         try {

   273             ia1[0] = 0;

   274             System.out.println(ia1[0]);

   275             Asserts.fail();

   276         } catch (NullPointerException e) {

   277             checkMessage(e, "ia1[0] = 0;", e.getMessage(),

   278                          "Cannot store to int array because " +

   279                          (hasDebugInfo ? "\"ia1\"" : "\"<local1>\"") + " is null");

   280         }

   281         // fastore

   282         try {

   283             fa1[0] = 0.7f;

   284             System.out.println(fa1[0]);

   285             Asserts.fail();

   286         } catch (NullPointerException e) {

   287             checkMessage(e, "fa1[0] = 0.7f;", e.getMessage(),

   288                          "Cannot store to float array because " +

   289                          (hasDebugInfo ? "\"fa1\"" : "\"<local2>\"") + " is null");

   290         }

   291         // aastore

   292         try {

   293             oa1[0] = new Object();

   294             System.out.println(oa1[0]);

   295             Asserts.fail();

   296         } catch (NullPointerException e) {

   297             checkMessage(e, "oa1[0] = new Object();", e.getMessage(),

   298                          "Cannot store to object array because " +

   299                          (hasDebugInfo ? "\"oa1\"" : "\"<local3>\"") + " is null");

   300         }

   301         // bastore (boolean)

   302         try {

   303             za1[0] = false;

   304             System.out.println(za1[0]);

   305             Asserts.fail();

   306         } catch (NullPointerException e) {

   307             checkMessage(e, "za1[0] = false;", e.getMessage(),

   308                          "Cannot store to byte/boolean array because " +

   309                          (hasDebugInfo ? "\"za1\"" : "\"<local4>\"") + " is null");

   310         }

   311         // bastore (byte)

   312         try {

   313             ba1[0] = 0;

   314             System.out.println(ba1[0]);

   315             Asserts.fail();

   316         } catch (NullPointerException e) {

   317             checkMessage(e, "ba1[0] = 0;", e.getMessage(),

   318                          "Cannot store to byte/boolean array because " +

   319                          (hasDebugInfo ? "\"ba1\"" : "\"<local5>\"") + " is null");

   320         }

   321         // castore

   322         try {

   323             ca1[0] = 0;

   324             System.out.println(ca1[0]);

   325             Asserts.fail();

   326         } catch (NullPointerException e) {

   327             checkMessage(e, "ca1[0] = 0;", e.getMessage(),

   328                          "Cannot store to char array because " +

   329                          (hasDebugInfo ? "\"ca1\"" : "\"<local6>\"") + " is null");

   330         }

   331         // sastore

   332         try {

   333             sa1[0] = 0;

   334             System.out.println(sa1[0]);

   335             Asserts.fail();

   336         } catch (NullPointerException e) {

   337             checkMessage(e, "sa1[0] = 0;", e.getMessage(),

   338                          "Cannot store to short array because " +

   339                          (hasDebugInfo ? "\"sa1\"" : "\"<local7>\"") + " is null");

   340         }

   341         // lastore

   342         try {

   343             la1[0] = 0;

   344             System.out.println(la1[0]);

   345             Asserts.fail();

   346         } catch (NullPointerException e) {

   347             checkMessage(e, "la1[0] = 0;", e.getMessage(),

   348                          "Cannot store to long array because " +

   349                          (hasDebugInfo ? "\"la1\"" : "\"<local8>\"") + " is null");

   350         }

   351         // dastore

   352         try {

   353             da1[0] = 0;

   354             System.out.println(da1[0]);

   355             Asserts.fail();

   356         } catch (NullPointerException e) {

   357             checkMessage(e, "da1[0] = 0;", e.getMessage(),

   358                          "Cannot store to double array because " +

   359                          (hasDebugInfo ? "\"da1\"" : "\"<local9>\"") + " is null");

   360         }

   361 

   362         // arraylength

   363         try {

   364             int val = za1.length;

   365             System.out.println(val);

   366             Asserts.fail();

   367         } catch (NullPointerException e) {

   368             checkMessage(e, " int val = za1.length;", e.getMessage(),

   369                          "Cannot read the array length because " +

   370                          (hasDebugInfo ? "\"za1\"" : "\"<local4>\"") + " is null");

   371         }

   372         // athrow

   373         try {

   374             RuntimeException exc = null;

   375             throw exc;

   376         } catch (NullPointerException e) {

   377             checkMessage(e, "throw exc;", e.getMessage(),

   378                          "Cannot throw exception because " +

   379                          (hasDebugInfo ? "\"exc\"" : "\"<local10>\"") + " is null");

   380         }

   381         // monitorenter

   382         try {

   383             synchronized (nullInstanceField) {

   384                 // desired

   385             }

   386         } catch (NullPointerException e) {

   387             checkMessage(e, "synchronized (nullInstanceField) { ... }", e.getMessage(),

   388                          "Cannot enter synchronized block because " +

   389                          "\"this.nullInstanceField\" is null");

   390         }

   391         // monitorexit

   392         // No test available

   393 

   394         // getfield

   395         try {

   396             Object val = nullInstanceField.nullInstanceField;

   397             System.out.println(val);

   398             Asserts.fail();

   399         } catch (NullPointerException e) {

   400             checkMessage(e, "Object val = nullInstanceField.nullInstanceField;", e.getMessage(),

   401                          "Cannot read field \"nullInstanceField\" because " +

   402                          "\"this.nullInstanceField\" is null");

   403         }

   404         // putfield

   405         try {

   406             nullInstanceField.nullInstanceField = new NullPointerExceptionTest();

   407             System.out.println(nullInstanceField.nullInstanceField);

   408             Asserts.fail();

   409         } catch (NullPointerException e) {

   410             checkMessage(e, "nullInstanceField.nullInstanceField = new NullPointerExceptionTest();", e.getMessage(),

   411                          "Cannot assign field \"nullInstanceField\" because " +

   412                          "\"this.nullInstanceField\" is null");

   413         }

   414         // invokevirtual

   415         try {

   416             String val = nullInstanceField.toString();

   417             System.out.println(val);

   418             Asserts.fail();

   419         } catch (NullPointerException e) {

   420             checkMessage(e, "String val = nullInstanceField.toString();", e.getMessage(),

   421                          "Cannot invoke \"Object.toString()\" because " +

   422                          "\"this.nullInstanceField\" is null");

   423         }

   424         // invokeinterface

   425         try {

   426             NullPointerExceptionTest obj = this;

   427             Object val = obj.dag.getArray();

   428             Asserts.assertNull(val);

   429             Asserts.fail();

   430         } catch (NullPointerException e) {

   431             checkMessage(e, "Object val = obj.dag.getArray();", e.getMessage(),

   432                          "Cannot invoke \"NullPointerExceptionTest$DoubleArrayGen.getArray()\" because " +

   433                          (hasDebugInfo ? "\"obj" : "\"<local10>") + ".dag\" is null");

   434         }

   435         // invokespecial

   436         G g = null;

   437         try {

   438             byte[] classBytes = G.generateSub2GTestClass();

   439             Lookup lookup = lookup();

   440             Class<?> clazz = lookup.defineClass(classBytes);

   441             g = (G) clazz.getDeclaredConstructor().newInstance();

   442         } catch (Exception e) {

   443             e.printStackTrace();

   444             Asserts.fail("Generating class Sub2G failed.");

   445         }

   446         try {

   447             g.m2("Beginning");

   448         } catch (NullPointerException e) {

   449             checkMessage(e, "return super.m2(x).substring(2); // ... where super is null by bytecode manipulation.", e.getMessage(),

   450                          "Cannot invoke \"G.m2(String)\" because \"null\" is null");

   451         }

   452         // Test parameter and return types

   453         try {

   454             boolean val = (nullInstanceField.callWithTypes(null, null, 0.0f, 0L, (short)0, false, (byte)0, 0.0, 'x') == 0.0);

   455             Asserts.assertTrue(val);

   456             Asserts.fail();

   457         } catch (NullPointerException e) {

   458             checkMessage(e, "boolean val = (nullInstanceField.callWithTypes(null, null, 0.0f, 0L, (short)0, false, (byte)0, 0.0, 'x') == 0.0);", e.getMessage(),

   459                          "Cannot invoke \"NullPointerExceptionTest.callWithTypes(String[][], int[][][], float, long, short, boolean, byte, double, char)\" because " +

   460                          "\"this.nullInstanceField\" is null");

   461         }

   462     }

   463 

   464     static void test_iload() {

   465         int i0 = 0;

   466         int i1 = 1;

   467         int i2 = 2;

   468         int i3 = 3;

   469         @SuppressWarnings("unused")

   470         int i4 = 4;

   471         int i5 = 5;

   472 

   473         int[][] a = new int[6][];

   474 

   475         // iload_0

   476         try {

   477             a[i0][0] = 77;

   478             Asserts.fail();

   479         } catch (NullPointerException e) {

   480             checkMessage(e, "a[i0][0] = 77;", e.getMessage(),

   481                          "Cannot store to int array because " +

   482                          (hasDebugInfo ? "\"a[i0]\"" : "\"<local6>[<local0>]\"") + " is null");

   483         }

   484         // iload_1

   485         try {

   486             a[i1][0] = 77;

   487             Asserts.fail();

   488         } catch (NullPointerException e) {

   489             checkMessage(e, "a[i1][0] = 77;", e.getMessage(),

   490                          "Cannot store to int array because " +

   491                          (hasDebugInfo ? "\"a[i1]\"" : "\"<local6>[<local1>]\"") + " is null");

   492         }

   493         // iload_2

   494         try {

   495             a[i2][0] = 77;

   496             Asserts.fail();

   497         } catch (NullPointerException e) {

   498             checkMessage(e, "a[i2][0] = 77;", e.getMessage(),

   499                          "Cannot store to int array because " +

   500                          (hasDebugInfo ? "\"a[i2]\"" : "\"<local6>[<local2>]\"") + " is null");

   501         }

   502         // iload_3

   503         try {

   504             a[i3][0] = 77;

   505             Asserts.fail();

   506         } catch (NullPointerException e) {

   507             checkMessage(e, "a[i3][0] = 77;", e.getMessage(),

   508                          "Cannot store to int array because " +

   509                          (hasDebugInfo ? "\"a[i3]\"" : "\"<local6>[<local3>]\"") + " is null");

   510         }

   511         // iload

   512         try {

   513             a[i5][0] = 77;

   514             Asserts.fail();

   515         } catch (NullPointerException e) {

   516             checkMessage(e, "a[i5][0] = 77;", e.getMessage(),

   517                          "Cannot store to int array because " +

   518                          (hasDebugInfo ? "\"a[i5]\"" : "\"<local6>[<local5>]\"") + " is null");

   519         }

   520     }

   521 

   522     // Other datatyes than int are not needed.

   523     // If we implement l2d and similar bytecodes, we can print

   524     // long expressions as array indexes. Then these here could

   525     // be used.

   526     static void test_lload() {

   527         long long0 = 0L;  // l0 looks like 10. Therefore long0.

   528         long long1 = 1L;

   529         long long2 = 2L;

   530         long long3 = 3L;

   531         @SuppressWarnings("unused")

   532         long long4 = 4L;

   533         long long5 = 5L;

   534 

   535         int[][] a = new int[6][];

   536 

   537         // lload_0

   538         try {

   539             a[(int)long0][0] = 77;

   540             Asserts.fail();

   541         } catch (NullPointerException e) {

   542             checkMessage(e, "a[(int)long0][0] = 77;", e.getMessage(),

   543                          "Cannot store to int array because " +

   544                          (hasDebugInfo ? "\"a[...]\"" : "\"<local12>[...]\"") + " is null");

   545         }

   546         // lload_1

   547         try {

   548             a[(int)long1][0] = 77;

   549             Asserts.fail();

   550         } catch (NullPointerException e) {

   551             checkMessage(e, "a[(int)long1][0] = 77;", e.getMessage(),

   552                          "Cannot store to int array because " +

   553                          (hasDebugInfo ? "\"a[...]\"" : "\"<local12>[...]\"") + " is null");

   554         }

   555         // lload_2

   556         try {

   557             a[(int)long2][0] = 77;

   558             Asserts.fail();

   559         } catch (NullPointerException e) {

   560             checkMessage(e, "a[(int)long2][0] = 77;", e.getMessage(),

   561                          "Cannot store to int array because " +

   562                          (hasDebugInfo ? "\"a[...]\"" : "\"<local12>[...]\"") + " is null");

   563         }

   564         // lload_3

   565         try {

   566             a[(int)long3][0] = 77;

   567             Asserts.fail();

   568         } catch (NullPointerException e) {

   569             checkMessage(e, "a[(int)long3][0] = 77;", e.getMessage(),

   570                          "Cannot store to int array because " +

   571                          (hasDebugInfo ? "\"a[...]\"" : "\"<local12>[...]\"") + " is null");

   572         }

   573         // lload

   574         try {

   575             a[(int)long5][0] = 77;

   576             Asserts.fail();

   577         } catch (NullPointerException e) {

   578             checkMessage(e, "a[(int)long5][0] = 77;", e.getMessage(),

   579                          "Cannot store to int array because " +

   580                          (hasDebugInfo ? "\"a[...]\"" : "\"<local12>[...]\"") + " is null");

   581         }

   582     }

   583 

   584     static void test_fload() {

   585         float f0 = 0.0f;

   586         float f1 = 1.0f;

   587         float f2 = 2.0f;

   588         float f3 = 3.0f;

   589         @SuppressWarnings("unused")

   590         float f4 = 4.0f;

   591         float f5 = 5.0f;

   592 

   593         int[][] a = new int[6][];

   594 

   595         // fload_0

   596         try {

   597             a[(int)f0][0] = 77;

   598             Asserts.fail();

   599         } catch (NullPointerException e) {

   600             checkMessage(e, "a[(int)f0][0] = 77;", e.getMessage(),

   601                          "Cannot store to int array because " +

   602                          (hasDebugInfo ? "\"a[...]\"" : "\"<local6>[...]\"") + " is null");

   603         }

   604         // fload_1

   605         try {

   606             a[(int)f1][0] = 77;

   607             Asserts.fail();

   608         } catch (NullPointerException e) {

   609             checkMessage(e, "a[(int)f1][0] = 77;", e.getMessage(),

   610                          "Cannot store to int array because " +

   611                          (hasDebugInfo ? "\"a[...]\"" : "\"<local6>[...]\"") + " is null");

   612         }

   613         // fload_2

   614         try {

   615             a[(int)f2][0] = 77;

   616             Asserts.fail();

   617         } catch (NullPointerException e) {

   618             checkMessage(e, "a[(int)f2][0] = 77;", e.getMessage(),

   619                          "Cannot store to int array because " +

   620                          (hasDebugInfo ? "\"a[...]\"" : "\"<local6>[...]\"") + " is null");

   621         }

   622         // fload_3

   623         try {

   624             a[(int)f3][0] = 77;

   625             Asserts.fail();

   626         } catch (NullPointerException e) {

   627             checkMessage(e, "a[(int)f3][0] = 77;", e.getMessage(),

   628                          "Cannot store to int array because " +

   629                          (hasDebugInfo ? "\"a[...]\"" : "\"<local6>[...]\"") + " is null");

   630         }

   631         // fload

   632         try {

   633             a[(int)f5][0] = 77;

   634             Asserts.fail();

   635         } catch (NullPointerException e) {

   636             checkMessage(e, "a[(int)f5][0] = 77;", e.getMessage(),

   637                          "Cannot store to int array because " +

   638                          (hasDebugInfo ? "\"a[...]\"" : "\"<local6>[...]\"") + " is null");

   639         }

   640     }

   641 

   642     @SuppressWarnings("null")

   643     static void test_aload() {

   644         F f0 = null;

   645         F f1 = null;

   646         F f2 = null;

   647         F f3 = null;

   648         @SuppressWarnings("unused")

   649         F f4 = null;

   650         F f5 = null;

   651 

   652         // aload_0

   653         try {

   654             f0.i = 33;

   655             Asserts.fail();

   656         } catch (NullPointerException e) {

   657             checkMessage(e, "f0.i = 33;", e.getMessage(),

   658                          "Cannot assign field \"i\" because " +

   659                          (hasDebugInfo ? "\"f0\"" : "\"<local0>\"") + " is null");

   660         }

   661         // aload_1

   662         try {

   663             f1.i = 33;

   664             Asserts.fail();

   665         } catch (NullPointerException e) {

   666             checkMessage(e, "f1.i = 33;", e.getMessage(),

   667                          "Cannot assign field \"i\" because " +

   668                          (hasDebugInfo ? "\"f1\"" : "\"<local1>\"") + " is null");

   669         }

   670         // aload_2

   671         try {

   672             f2.i = 33;

   673             Asserts.fail();

   674         } catch (NullPointerException e) {

   675             checkMessage(e, "f2.i = 33;", e.getMessage(),

   676                          "Cannot assign field \"i\" because " +

   677                          (hasDebugInfo ? "\"f2\"" : "\"<local2>\"") + " is null");

   678         }

   679         // aload_3

   680         try {

   681             f3.i = 33;

   682             Asserts.fail();

   683         } catch (NullPointerException e) {

   684             checkMessage(e, "f3.i = 33;", e.getMessage(),

   685                          "Cannot assign field \"i\" because " +

   686                          (hasDebugInfo ? "\"f3\"" : "\"<local3>\"") + " is null");

   687         }

   688         // aload

   689         try {

   690             f5.i = 33;

   691             Asserts.fail();

   692         } catch (NullPointerException e) {

   693             checkMessage(e, "f5.i = 33;", e.getMessage(),

   694                          "Cannot assign field \"i\" because " +

   695                          (hasDebugInfo ? "\"f5\"" : "\"<local5>\"") + " is null");

   696         }

   697     }

   698 

   699     // Helper class for test cases.

   700     class A {

   701         public B to_b;

   702         public B getB() { return to_b; }

   703     }

   704 

   705     // Helper class for test cases.

   706     class B {

   707         public C to_c;

   708         public B to_b;

   709         public C getC() { return to_c; }

   710         public B getBfromB() { return to_b; }

   711     }

   712 

   713     // Helper class for test cases.

   714     class C {

   715         public D to_d;

   716         public D getD() { return to_d; }

   717     }

   718 

   719     // Helper class for test cases.

   720     class D {

   721         public int num;

   722         public int[][] ar;

   723     }

   724 

   725 

   726     @SuppressWarnings("null")

   727     public void testArrayChasing() {

   728         int[][][][][][] a = null;

   729         try {

   730             a[0][0][0][0][0][0] = 99;

   731             Asserts.fail();

   732         } catch (NullPointerException e) {

   733             checkMessage(e, "a[0][0][0][0][0] = 99; // a is null", e.getMessage(),

   734                          "Cannot load from object array because " +

   735                          (hasDebugInfo ? "\"a\"" : "\"<local1>\"") + " is null");

   736         }

   737         a = new int[1][][][][][];

   738         try {

   739             a[0][0][0][0][0][0] = 99;

   740             Asserts.fail();

   741         } catch (NullPointerException e) {

   742             checkMessage(e, "a[0][0][0][0][0] = 99; // a[0] is null", e.getMessage(),

   743                          "Cannot load from object array because " +

   744                          (hasDebugInfo ? "\"a[0]\"" : "\"<local1>[0]\"") + " is null");

   745         }

   746         a[0] = new int[1][][][][];

   747         try {

   748             a[0][0][0][0][0][0] = 99;

   749             Asserts.fail();

   750         } catch (NullPointerException e) {

   751             checkMessage(e, "a[0][0][0][0][0] = 99; // a[0][0] is null", e.getMessage(),

   752                          "Cannot load from object array because " +

   753                          (hasDebugInfo ? "\"a[0][0]\"" : "\"<local1>[0][0]\"") + " is null");

   754         }

   755         a[0][0] = new int[1][][][];

   756         try {

   757             a[0][0][0][0][0][0] = 99;

   758             Asserts.fail();

   759         } catch (NullPointerException e) {

   760             checkMessage(e, "a[0][0][0][0][0] = 99; // a[0][0][0] is null", e.getMessage(),

   761                          "Cannot load from object array because " +

   762                          (hasDebugInfo ? "\"a[0][0][0]\"" : "\"<local1>[0][0][0]\"") + " is null");

   763         }

   764         try {

   765             System.out.println(a[0][0][0].length);

   766             Asserts.fail();

   767         } catch (NullPointerException e) {

   768             checkMessage(e, "a[0][0][0].length; // a[0][0][0] is null", e.getMessage(),

   769                          "Cannot read the array length because " +

   770                          (hasDebugInfo ? "\"a[0][0][0]\"" : "\"<local1>[0][0][0]\"") + " is null");

   771         }

   772         a[0][0][0] = new int[1][][];

   773         try {

   774             a[0][0][0][0][0][0] = 99;

   775             Asserts.fail();

   776         } catch (NullPointerException e) {

   777             checkMessage(e, "a[0][0][0][0][0] = 99; // a[0][0][0][0] is null", e.getMessage(),

   778                          "Cannot load from object array because " +

   779                          (hasDebugInfo ? "\"a[0][0][0][0]\"" : "\"<local1>[0][0][0][0]\"") + " is null");

   780         }

   781         a[0][0][0][0] = new int[1][];

   782         // Reaching max recursion depth. Prints <array>.

   783         try {

   784             a[0][0][0][0][0][0] = 99;

   785             Asserts.fail();

   786         } catch (NullPointerException e) {

   787             checkMessage(e, "a[0][0][0][0][0] = 99; // a[0][0][0][0][0] is null", e.getMessage(),

   788                          "Cannot store to int array because " +

   789                          "\"<array>[0][0][0][0][0]\" is null");

   790         }

   791         a[0][0][0][0][0] = new int[1];

   792         try {

   793             a[0][0][0][0][0][0] = 99;

   794         } catch (NullPointerException e) {

   795             Asserts.fail();

   796         }

   797     }

   798 

   799     @SuppressWarnings("null")

   800     public void testPointerChasing() {

   801         A a = null;

   802         try {

   803             a.to_b.to_c.to_d.num = 99;

   804             Asserts.fail();

   805         } catch (NullPointerException e) {

   806             checkMessage(e, "a.to_b.to_c.to_d.num = 99; // a is null", e.getMessage(),

   807                          "Cannot read field \"to_b\" because " +

   808                          (hasDebugInfo ? "\"a\"" : "\"<local1>\"") + " is null");

   809         }

   810         a = new A();

   811         try {

   812             a.to_b.to_c.to_d.num = 99;

   813             Asserts.fail();

   814         } catch (NullPointerException e) {

   815             checkMessage(e, "a.to_b.to_c.to_d.num = 99; // a.to_b is null", e.getMessage(),

   816                          "Cannot read field \"to_c\" because " +

   817                          (hasDebugInfo ? "\"a.to_b\"" : "\"<local1>.to_b\"") + " is null");

   818         }

   819         a.to_b = new B();

   820         try {

   821             a.to_b.to_c.to_d.num = 99;

   822             Asserts.fail();

   823         } catch (NullPointerException e) {

   824             checkMessage(e, "a.to_b.to_c.to_d.num = 99; // a.to_b.to_c is null", e.getMessage(),

   825                          "Cannot read field \"to_d\" because " +

   826                          (hasDebugInfo ? "\"a.to_b.to_c\"" : "\"<local1>.to_b.to_c\"") + " is null");

   827         }

   828         a.to_b.to_c = new C();

   829         try {

   830             a.to_b.to_c.to_d.num = 99;

   831             Asserts.fail();

   832         } catch (NullPointerException e) {

   833             checkMessage(e, "a.to_b.to_c.to_d.num = 99; // a.to_b.to_c.to_d is null", e.getMessage(),

   834                          "Cannot assign field \"num\" because " +

   835                          (hasDebugInfo ? "\"a.to_b.to_c.to_d\"" : "\"<local1>.to_b.to_c.to_d\"") + " is null");

   836         }

   837     }

   838 

   839     @SuppressWarnings("null")

   840     public void testMethodChasing() {

   841         A a = null;

   842         try {

   843             a.getB().getBfromB().getC().getD().num = 99;

   844             Asserts.fail();

   845         } catch (NullPointerException e) {

   846             checkMessage(e, "a.getB().getBfromB().getC().getD().num = 99; // a is null", e.getMessage(),

   847                          "Cannot invoke \"NullPointerExceptionTest$A.getB()\" because " +

   848                          (hasDebugInfo ? "\"a" : "\"<local1>") + "\" is null");

   849         }

   850         a = new A();

   851         try {

   852             a.getB().getBfromB().getC().getD().num = 99;

   853             Asserts.fail();

   854         } catch (NullPointerException e) {

   855             checkMessage(e, "a.getB().getBfromB().getC().getD().num = 99; // a.getB() is null", e.getMessage(),

   856                          "Cannot invoke \"NullPointerExceptionTest$B.getBfromB()\" because " +

   857                          "the return value of \"NullPointerExceptionTest$A.getB()\" is null");

   858         }

   859         a.to_b = new B();

   860         try {

   861             a.getB().getBfromB().getC().getD().num = 99;

   862             Asserts.fail();

   863         } catch (NullPointerException e) {

   864             checkMessage(e, "a.getB().getBfromB().getC().getD().num = 99; // a.getB().getBfromB() is null", e.getMessage(),

   865                          "Cannot invoke \"NullPointerExceptionTest$B.getC()\" because " +

   866                          "the return value of \"NullPointerExceptionTest$B.getBfromB()\" is null");

   867         }

   868         a.to_b.to_b = new B();

   869         try {

   870             a.getB().getBfromB().getC().getD().num = 99;

   871             Asserts.fail();

   872         } catch (NullPointerException e) {

   873             checkMessage(e, "a.getB().getBfromB().getC().getD().num = 99; // a.getB().getBfromB().getC() is null", e.getMessage(),

   874                          "Cannot invoke \"NullPointerExceptionTest$C.getD()\" because " +

   875                          "the return value of \"NullPointerExceptionTest$B.getC()\" is null");

   876         }

   877         a.to_b.to_b.to_c = new C();

   878         try {

   879             a.getB().getBfromB().getC().getD().num = 99;

   880             Asserts.fail();

   881         } catch (NullPointerException e) {

   882             checkMessage(e, "a.getB().getBfromB().getC().getD().num = 99; // a.getB().getBfromB().getC().getD() is null", e.getMessage(),

   883                          "Cannot assign field \"num\" because " +

   884                          "the return value of \"NullPointerExceptionTest$C.getD()\" is null");

   885         }

   886     }

   887 

   888     @SuppressWarnings("null")

   889     public void testMixedChasing() {

   890         A a = null;

   891         try {

   892             a.getB().getBfromB().to_c.to_d.ar[0][0] = 99;

   893             Asserts.fail();

   894         } catch (NullPointerException e) {

   895             checkMessage(e, "a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a is null", e.getMessage(),

   896                          "Cannot invoke \"NullPointerExceptionTest$A.getB()\" because " +

   897                          (hasDebugInfo ? "\"a\"" : "\"<local1>\"") + " is null");

   898         }

   899         a = new A();

   900         try {

   901             a.getB().getBfromB().to_c.to_d.ar[0][0] = 99;

   902             Asserts.fail();

   903         } catch (NullPointerException e) {

   904             checkMessage(e, "a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB() is null", e.getMessage(),

   905                          "Cannot invoke \"NullPointerExceptionTest$B.getBfromB()\" because " +

   906                          "the return value of \"NullPointerExceptionTest$A.getB()\" is null");

   907         }

   908         a.to_b = new B();

   909         try {

   910             a.getB().getBfromB().to_c.to_d.ar[0][0] = 99;

   911             Asserts.fail();

   912         } catch (NullPointerException e) {

   913             checkMessage(e, "a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB() is null", e.getMessage(),

   914                          "Cannot read field \"to_c\" because " +

   915                          "the return value of \"NullPointerExceptionTest$B.getBfromB()\" is null");

   916         }

   917         a.to_b.to_b = new B();

   918         try {

   919             a.getB().getBfromB().to_c.to_d.ar[0][0] = 99;

   920             Asserts.fail();

   921         } catch (NullPointerException e) {

   922             checkMessage(e, "a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c is null", e.getMessage(),

   923                          "Cannot read field \"to_d\" because " +

   924                          "\"NullPointerExceptionTest$B.getBfromB().to_c\" is null");

   925         }

   926         a.to_b.to_b.to_c = new C();

   927         try {

   928             a.getB().getBfromB().to_c.to_d.ar[0][0] = 99;

   929             Asserts.fail();

   930         } catch (NullPointerException e) {

   931             checkMessage(e, "a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c.to_d is null", e.getMessage(),

   932                          "Cannot read field \"ar\" because " +

   933                          "\"NullPointerExceptionTest$B.getBfromB().to_c.to_d\" is null");

   934         }

   935         a.to_b.to_b.to_c.to_d = new D();

   936         try {

   937             a.getB().getBfromB().to_c.to_d.ar[0][0] = 99;

   938             Asserts.fail();

   939         } catch (NullPointerException e) {

   940             checkMessage(e, "a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c.to_d.ar is null", e.getMessage(),

   941                          "Cannot load from object array because " +

   942                          "\"NullPointerExceptionTest$B.getBfromB().to_c.to_d.ar\" is null");

   943         }

   944         try {

   945             a.getB().getBfromB().getC().getD().ar[0][0] = 99;

   946             Asserts.fail();

   947         } catch (NullPointerException e) {

   948             checkMessage(e, "a.getB().getBfromB().getC().getD().ar[0][0] = 99; // a.getB().getBfromB().getC().getD().ar is null", e.getMessage(),

   949                          "Cannot load from object array because " +

   950                          "\"NullPointerExceptionTest$C.getD().ar\" is null");

   951         }

   952         a.to_b.to_b.to_c.to_d.ar = new int[1][];

   953         try {

   954             a.getB().getBfromB().to_c.to_d.ar[0][0] = 99;

   955             Asserts.fail();

   956         } catch (NullPointerException e) {

   957             checkMessage(e, "a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c.to_d.ar[0] is null", e.getMessage(),

   958                          "Cannot store to int array because " +

   959                          "\"NullPointerExceptionTest$B.getBfromB().to_c.to_d.ar[0]\" is null");

   960         }

   961         try {

   962             a.getB().getBfromB().getC().getD().ar[0][0] = 99;

   963             Asserts.fail();

   964         } catch (NullPointerException e) {

   965             checkMessage(e, "a.getB().getBfromB().getC().getD().ar[0][0] = 99; // a.getB().getBfromB().getC().getD().ar[0] is null", e.getMessage(),

   966                          "Cannot store to int array because " +

   967                          "\"NullPointerExceptionTest$C.getD().ar[0]\" is null");

   968         }

   969     }

   970 

   971     // Helper method to cause test case.

   972     private Object returnNull(String[][] dummy1, int[][][] dummy2, float dummy3) {

   973         return null;

   974     }

   975 

   976     // Helper method to cause test case.

   977     private NullPointerExceptionTest returnMeAsNull(Throwable dummy1, int dummy2, char dummy3) {

   978         return null;

   979     }

   980 

   981     // Helper interface for test cases.

   982     static interface DoubleArrayGen {

   983         public double[] getArray();

   984     }

   985 

   986     // Helper class for test cases.

   987     static class DoubleArrayGenImpl implements DoubleArrayGen {

   988         @Override

   989         public double[] getArray() {

   990             return null;

   991         }

   992     }

   993 

   994     // Helper class for test cases.

   995     static class NullPointerGenerator {

   996         public static Object nullReturner(boolean dummy1) {

   997             return null;

   998         }

   999 

  1000         public Object returnMyNull(double dummy1, long dummy2, short dummy3) {

  1001             return null;

  1002         }

  1003     }

  1004 

  1005     // Helper method to cause test case.

  1006     public void ImplTestLoadedFromMethod(DoubleArrayGen gen) {

  1007         try {

  1008             (gen.getArray())[0] = 1.0;

  1009             Asserts.fail();

  1010         } catch (NullPointerException e) {

  1011             checkMessage(e, "(gen.getArray())[0] = 1.0;", e.getMessage(),

  1012                          "Cannot store to double array because " +

  1013                          "the return value of \"NullPointerExceptionTest$DoubleArrayGen.getArray()\" is null");

  1014         }

  1015     }

  1016 

  1017     public void testNullEntity() {

  1018         int[][] a = new int[820][];

  1019 

  1020         test_iload();

  1021         test_lload();

  1022         test_fload();

  1023         // test_dload();

  1024         test_aload();

  1025         // aload_0: 'this'

  1026         try {

  1027             this.nullInstanceField.nullInstanceField = new NullPointerExceptionTest();

  1028             Asserts.fail();

  1029         } catch (NullPointerException e) {

  1030             checkMessage(e, "this.nullInstanceField.nullInstanceField = new NullPointerExceptionTest();", e.getMessage(),

  1031                          "Cannot assign field \"nullInstanceField\" because \"this.nullInstanceField\" is null");

  1032         }

  1033 

  1034         // aconst_null

  1035         try {

  1036             throw null;

  1037         } catch (NullPointerException e) {

  1038             checkMessage(e, "throw null;", e.getMessage(),

  1039                          "Cannot throw exception because \"null\" is null");

  1040         }

  1041         // iconst_0

  1042         try {

  1043             a[0][0] = 77;

  1044             Asserts.fail();

  1045         } catch (NullPointerException e) {

  1046             checkMessage(e, "a[0][0] = 77;", e.getMessage(),

  1047                          "Cannot store to int array because " +

  1048                          (hasDebugInfo ? "\"a[0]\"" : "\"<local1>[0]\"") + " is null");

  1049         }

  1050         // iconst_1

  1051         try {

  1052             a[1][0] = 77;

  1053             Asserts.fail();

  1054         } catch (NullPointerException e) {

  1055             checkMessage(e, "a[1][0] = 77;", e.getMessage(),

  1056                          "Cannot store to int array because " +

  1057                          (hasDebugInfo ? "\"a[1]\"" : "\"<local1>[1]\"") + " is null");

  1058         }

  1059         // iconst_2

  1060         try {

  1061             a[2][0] = 77;

  1062             Asserts.fail();

  1063         } catch (NullPointerException e) {

  1064             checkMessage(e, "a[2][0] = 77;", e.getMessage(),

  1065                          "Cannot store to int array because " +

  1066                          (hasDebugInfo ? "\"a[2]\"" : "\"<local1>[2]\"") + " is null");

  1067         }

  1068         // iconst_3

  1069         try {

  1070             a[3][0] = 77;

  1071             Asserts.fail();

  1072         } catch (NullPointerException e) {

  1073             checkMessage(e, "a[3][0] = 77;", e.getMessage(),

  1074                          "Cannot store to int array because " +

  1075                          (hasDebugInfo ? "\"a[3]\"" : "\"<local1>[3]\"") + " is null");

  1076         }

  1077         // iconst_4

  1078         try {

  1079             a[4][0] = 77;

  1080             Asserts.fail();

  1081         } catch (NullPointerException e) {

  1082             checkMessage(e, "a[4][0] = 77;", e.getMessage(),

  1083                          "Cannot store to int array because " +

  1084                          (hasDebugInfo ? "\"a[4]\"" : "\"<local1>[4]\"") + " is null");

  1085         }

  1086         // iconst_5

  1087         try {

  1088             a[5][0] = 77;

  1089             Asserts.fail();

  1090         } catch (NullPointerException e) {

  1091             checkMessage(e, "a[5][0] = 77;", e.getMessage(),

  1092                          "Cannot store to int array because " +

  1093                          (hasDebugInfo ? "\"a[5]\"" : "\"<local1>[5]\"") + " is null");

  1094         }

  1095         // long --> iconst

  1096         try {

  1097             a[(int)0L][0] = 77;

  1098             Asserts.fail();

  1099         } catch (NullPointerException e) {

  1100             checkMessage(e, "a[(int)0L][0] = 77;", e.getMessage(),

  1101                          "Cannot store to int array because " +

  1102                          (hasDebugInfo ? "\"a[0]\"" : "\"<local1>[0]\"") + " is null");

  1103         }

  1104         // bipush

  1105         try {

  1106             a[139 /*0x77*/][0] = 77;

  1107             Asserts.fail();

  1108         } catch (NullPointerException e) {

  1109             checkMessage(e, "a[139][0] = 77;", e.getMessage(),

  1110                          "Cannot store to int array because " +

  1111                          (hasDebugInfo ? "\"a[139]\"" : "\"<local1>[139]\"") + " is null");

  1112         }

  1113         // sipush

  1114         try {

  1115             a[819 /*0x333*/][0] = 77;

  1116             Asserts.fail();

  1117         } catch (NullPointerException e) {

  1118             checkMessage(e, "a[819][0] = 77;", e.getMessage(),

  1119                          "Cannot store to int array because " +

  1120                          (hasDebugInfo ? "\"a[819]\"" : "\"<local1>[819]\"") + " is null");

  1121         }

  1122 

  1123         // aaload, with recursive descend.

  1124         testArrayChasing();

  1125 

  1126         // getstatic

  1127         try {

  1128             boolean val = (((float[]) nullStaticField)[0] == 1.0f);

  1129             Asserts.assertTrue(val);

  1130             Asserts.fail();

  1131         } catch (NullPointerException e) {

  1132             checkMessage(e, "boolean val = (((float[]) nullStaticField)[0] == 1.0f);", e.getMessage(),

  1133                          "Cannot load from float array because \"NullPointerExceptionTest.nullStaticField\" is null");

  1134         }

  1135 

  1136         // getfield, with recursive descend.