RFR: 8332086: Remove the usage of ServiceLoader in j.u.r.RandomGeneratorFactory [v5]

[Jaikiran Pai]

On Wed, 15 May 2024 09:51:23 GMT, Raffaello Giulietti <rgiulietti at openjdk.org> wrote:

>> All random number generator algorithms are implemented in module `java.base`. The usage of `ServiceLoader` in `j.u.r.RandomGeneratorFactory` is no longer needed.
>
> Raffaello Giulietti has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Small documentation changes.

test/jdk/java/util/Random/RandomTestCoverage.java line 179:

> 177:         try {
> 178:             rng = factory.create(12345L);
> 179:         } catch (UnsupportedOperationException ignore) {

I think now that we know for sure which algorithm instances don't support which type of seed value and since throwing `UnsupportedOperationException` is now a specification of the `create(...)` methods, we should probably do something like this:


diff --git a/test/jdk/java/util/Random/RandomTestCoverage.java b/test/jdk/java/util/Random/RandomTestCoverage.java
index be12d188198..6e5c36e13c3 100644
--- a/test/jdk/java/util/Random/RandomTestCoverage.java
+++ b/test/jdk/java/util/Random/RandomTestCoverage.java
@@ -171,8 +171,37 @@ static void coverFactory(RandomGeneratorFactory factory) {
         boolean isSplittable = factory.isSplittable();
 
         coverRandomGenerator(factory.create());
-        coverRandomGenerator(factory.create(12345L));
-        coverRandomGenerator(factory.create(new byte[] {1, 2, 3, 4, 5, 6, 7, 8}));
+
+        String algo = factory.name();
+        // test create(long)
+        switch (algo) {
+            // SecureRandom doesn't have long constructors so we expect
+            // UnsupportedOperationException
+            case "SecureRandom" -> {
+                try {
+                    factory.create(12345L);
+                    throw new AssertionError("RandomGeneratorFactory.create(long) was expected" +
+                            "to throw UnsupportedOperationException for " + algo + " but didn't");
+                } catch (UnsupportedOperationException uoe) {
+                    // expected
+                }
+            }
+            default -> coverRandomGenerator(factory.create(12345L));
+        }
+        // test create(byte[])
+        switch (algo) {
+            // these don't have byte[] constructors so we expect UnsupportedOperationException
+            case "Random", "SplittableRandom" -> {
+                try {
+                    factory.create(new byte[] {1, 2, 3, 4, 5, 6, 7, 8});
+                    throw new AssertionError("RandomGeneratorFactory.create(byte[]) was expected" +
+                            "to throw UnsupportedOperationException for " + algo + " but didn't");
+                } catch (UnsupportedOperationException uoe) {
+                    // expected
+                }
+            }
+            default -> coverRandomGenerator(factory.create(new byte[] {1, 2, 3, 4, 5, 6, 7, 8}));
+        }
     }

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/19212#discussion_r1603123836