GenericStringTest.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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/*
 * @test
 * @bug 6298888 6992705 8161500 6304578
 * @summary Check Class.toGenericString()
 * @author Joseph D. Darcy
 */

import java.lang.reflect.*;
import java.lang.annotation.*;
import java.util.*;

@ExpectedGenericString("public class GenericStringTest")
public class GenericStringTest {
    public Map<String, Integer>[] mixed = null;
    public Map<String, Integer>[][] mixed2 = null;

    public static void main(String... args) throws ReflectiveOperationException {
        int failures = 0;

        String[][] nested = {{""}};
        int[][]    intArray = {{1}};

        Map<Class<?>, String> testCases =
            Map.of(int.class,                          "int",
                   void.class,                         "void",
                   args.getClass(),                    "java.lang.String[]",
                   nested.getClass(),                  "java.lang.String[][]",
                   intArray.getClass(),                "int[][]",
                   java.lang.Enum.class,               "public abstract class java.lang.Enum<E extends java.lang.Enum<E>>",
                   java.util.Map.class,                "public abstract interface java.util.Map<K,V>",
                   java.util.EnumMap.class,            "public class java.util.EnumMap<K extends java.lang.Enum<K>,V>",
                   java.util.EventListenerProxy.class, "public abstract class java.util.EventListenerProxy<T extends java.util.EventListener>");

        for (Map.Entry<Class<?>, String> testCase : testCases.entrySet()) {
            failures += checkToGenericString(testCase.getKey(), testCase.getValue());
        }

        Field f = GenericStringTest.class.getDeclaredField("mixed");
        // The expected value includes "<K,V>" rather than
        // "<...String,...Integer>" since the Class object rather than
        // Type objects is being queried.
        failures += checkToGenericString(f.getType(), "java.util.Map<K,V>[]");
        f = GenericStringTest.class.getDeclaredField("mixed2");
        failures += checkToGenericString(f.getType(), "java.util.Map<K,V>[][]");

        for(Class<?> clazz : List.of(GenericStringTest.class,
                                     AnInterface.class,
                                     LocalMap.class,
                                     AnEnum.class,
                                     AnotherEnum.class)) {
            failures += checkToGenericString(clazz, clazz.getAnnotation(ExpectedGenericString.class).value());
        }

        if (failures > 0) {
            throw new RuntimeException();
        }
    }

    private static int checkToGenericString(Class<?> clazz, String expected) {
        String genericString = clazz.toGenericString();
        if (!genericString.equals(expected)) {
            System.err.printf("Unexpected Class.toGenericString output; expected %n\t'%s',%n got %n\t'%s'.%n",
                              expected,
                              genericString);
            return 1;
        } else
            return 0;
    }
}

@Retention(RetentionPolicy.RUNTIME)
@interface ExpectedGenericString {
    String value();
}

@ExpectedGenericString("abstract interface AnInterface")
strictfp interface AnInterface {}

@ExpectedGenericString("abstract interface LocalMap<K,V>")
interface LocalMap<K,V> {}

@ExpectedGenericString("final enum AnEnum")
enum AnEnum {
    FOO;
}

@ExpectedGenericString("enum AnotherEnum")
enum AnotherEnum {
    BAR{};
}