fix: tweak code and tests to better support Java 21

- adapt code in OFCChecker to a slight rewording of the OpenJDK message
  reported for invalid ZIP headers, so that EPUBCheck can issue the right
  error code (PKG-017)
- update the command line tests to no longer rely on the deprecated
  SecurityManager API to catch system exit codes. The tests now get
  the integer return code directly from the EpubChecker API

src/main/java/com/adobe/epubcheck/ocf/OCFChecker.java

@@ -345,15 +345,18 @@ private boolean checkContainerStructure(OCFCheckerState state)
       return true;
     } catch (Exception e)
     {
-      switch (e.getMessage())
+      if (e.getMessage() != null &&
+          (
+          // reported by Open JDK:
+          e.getMessage().startsWith("invalid CEN header")
+              // reported by Oracle JDK 1.8:
+              || e.getMessage().equals("MALFORMED")))
       {
-      case "invalid CEN header (bad entry name)": // reported by OpenJDK
-      case "MALFORMED": // reported by Oracle JDK 1.8
         report.message(MessageId.PKG_027, EPUBLocation.of(context), e.getLocalizedMessage());
-        break;
-      default:
+      }
+      else
+      {
         report.message(MessageId.PKG_008, EPUBLocation.of(context), e.getLocalizedMessage());
-        break;
       }
       return false;
     }
@@ -556,7 +559,8 @@ private void reportFeatures(OCFResource resource)
   {
     for (FeatureEnum feature : resource.getProperties().keySet())
     {
-//      report.info(context.path, feature, resource.getProperties().get(feature));
+      // report.info(context.path, feature,
+      // resource.getProperties().get(feature));
       report.info(resource.getPath(), feature, resource.getProperties().get(feature));
     }
   }

src/test/java/com/adobe/epubcheck/tools/CommandLineTest.java

@@ -22,7 +22,7 @@
 import org.junit.Test;
 
 import com.adobe.epubcheck.api.EpubCheck;
-import com.adobe.epubcheck.tool.Checker;
+import com.adobe.epubcheck.tool.EpubChecker;
 import com.adobe.epubcheck.util.Messages;
 
 public class CommandLineTest
@@ -35,7 +35,6 @@ public class CommandLineTest
   private final ByteArrayOutputStream outContent = new ByteArrayOutputStream();
   private final ByteArrayOutputStream errContent = new ByteArrayOutputStream();
 
-  private SecurityManager originalManager;
   private PrintStream originalOut;
   private PrintStream originalErr;
   private final Messages messages = Messages.getInstance(Locale.ENGLISH);
@@ -46,8 +45,6 @@ public void setUp()
   {
     defaultLocale = Locale.getDefault();
     Locale.setDefault(Locale.ENGLISH);
-    this.originalManager = System.getSecurityManager();
-    System.setSecurityManager(new NoExitSecurityManager());
     originalOut = System.out;
     originalErr = System.err;
     System.setOut(new PrintStream(outContent));
@@ -58,7 +55,6 @@ public void setUp()
   public void tearDown()
   {
     Locale.setDefault(defaultLocale);
-    System.setSecurityManager(this.originalManager);
     System.setOut(originalOut);
     System.setErr(originalErr);
   }
@@ -292,14 +288,7 @@ public void missingTranslationShouldFallbackTest()
     Locale.setDefault(Locale.FRANCE);
 
     URL inputUrl = CommandLineTest.class.getResource("valid.epub");
-
-    try
-    {
-      Checker.main(new String[] { inputUrl.getPath(), "--locale", "ar-eg" });
-    } catch (NoExitSecurityManager.ExitException e)
-    {
-      assertEquals("Return code should be zero", 0, e.status);
-    }
+    runCommandLineTest(0, inputUrl.getPath(), "--locale", "ar-eg");
 
     assertTrue("Valid Locale without translation should fallback to JVM default.",
         outContent.toString().contains("faites en utilisant"));
@@ -345,13 +334,7 @@ public void incorrectLocaleShouldFailTest()
 
     URL inputUrl = CommandLineTest.class.getResource("valid.epub");
 
-    try
-    {
-      Checker.main(new String[] { inputUrl.getPath(), "--locale", "foobar" });
-    } catch (NoExitSecurityManager.ExitException e)
-    {
-      assertEquals("Return code should be zero", 0, e.status);
-    }
+    runCommandLineTest(0, inputUrl.getPath(), "--locale", "foobar");
 
     assertTrue("Invalid Locale should use JVM default.",
         outContent.toString().contains("faites en utilisant"));
@@ -756,18 +739,11 @@ public void xmpFileTest()
     }
   }
 
-  public static void runCommandLineTest(int expectedReturnCode, String... args)
+  public void runCommandLineTest(int expectedReturnCode, String... args)
   {
-    int result = Integer.MAX_VALUE;
-    try
-    {
-      Checker.main(args);
-    } catch (NoExitSecurityManager.ExitException e)
-    {
-      result = e.status;
-    }
 
-    assertEquals("Return code", expectedReturnCode, result);
+    int returnCode = new EpubChecker().run(args);
+    assertEquals("Return code", expectedReturnCode, returnCode);
   }
 
 }