fix: build failing on Windows (#4484) (#4504)

Change path handling to correctly handle Windows pathnames.

Change line ending handling from using `System.lineSeparator` to using
the regex \R to treat all unicode line ending character sequences as the
line endings.

Change unit tests that compared certificates read from file, to ignore
the line ending characters, so differences in line ending did not break
the test.

Refs: #4484

core/common/connector-core/src/test/java/org/eclipse/edc/connector/core/LocalPublicKeyDefaultExtensionTest.java

@@ -26,6 +26,7 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 
+import java.nio.file.Paths;
 import java.security.PublicKey;
 import java.util.Map;
 
@@ -73,7 +74,7 @@ void localPublicKeyService_withPathConfig(LocalPublicKeyDefaultExtension extensi
         var value = TestUtils.getResourceFileContentAsString("rsa_2048.pem");
         var keys = Map.of(
                 "key1.id", "key1",
-                "key1.path", path.getPath());
+                "key1.path", Paths.get(path).toString());
 
         when(keyParserRegistry.parsePublic(value)).thenReturn(Result.success(mock(PublicKey.class)));
         when(context.getConfig(EDC_PUBLIC_KEYS_PREFIX)).thenReturn(ConfigFactory.fromMap(keys));

core/common/junit/src/main/java/org/eclipse/edc/junit/extensions/ClasspathReader.java

@@ -40,6 +40,9 @@ public class ClasspathReader {
      */
     public static URL[] classpathFor(String... modules) {
         try {
+            if (modules.length == 0) {
+                return new URL[0];
+            }
             // Run a Gradle custom task to determine the runtime classpath of the module to run
             var printClasspath = Arrays.stream(modules).map(it -> it + ":printClasspath");
             var commandStream = Stream.of(GRADLE_WRAPPER.getCanonicalPath(), "-q");

core/common/lib/keys-lib/src/main/java/org/eclipse/edc/keys/VaultCertificateResolver.java

@@ -47,7 +47,7 @@ public VaultCertificateResolver(@NotNull Vault vault) {
         }
 
         try {
-            var encoded = certificateRepresentation.replace(HEADER, "").replaceAll(System.lineSeparator(), "").replace(FOOTER, "");
+            var encoded = certificateRepresentation.replace(HEADER, "").replaceAll("\\R", "").replace(FOOTER, "");
             CertificateFactory fact = CertificateFactory.getInstance("X.509");
             return (X509Certificate) fact.generateCertificate(new ByteArrayInputStream(Base64.getDecoder().decode(encoded.getBytes())));
         } catch (GeneralSecurityException | IllegalArgumentException e) {

core/common/lib/keys-lib/src/test/java/org/eclipse/edc/keys/VaultCertificateResolverTest.java

@@ -58,7 +58,7 @@ void resolveCertificate() throws RuntimeException, IOException {
         var pemReceived = convertCertificateToPem(certificate);
 
         verify(vault, times(1)).resolveSecret(KEY);
-        assertThat(pemReceived).isEqualTo(pemExpected);
+        assertThat(pemReceived.split("\\R")).isEqualTo(pemExpected.split("\\R"));
     }
 
     @Test

extensions/common/iam/oauth2/oauth2-core/src/test/java/org/eclipse/edc/iam/oauth2/jwt/X509CertificateDecoratorTest.java

@@ -36,7 +36,7 @@ class X509CertificateDecoratorTest {
     private static X509Certificate createCertificate() throws CertificateException, IOException {
         var classloader = Thread.currentThread().getContextClassLoader();
         var pem = new String(Objects.requireNonNull(classloader.getResourceAsStream(TEST_CERT_FILE)).readAllBytes());
-        var encoded = pem.replace(HEADER, "").replaceAll(System.lineSeparator(), "").replace(FOOTER, "");
+        var encoded = pem.replace(HEADER, "").replaceAll("\\R", "").replace(FOOTER, "");
         CertificateFactory fact = CertificateFactory.getInstance("X.509");
         return (X509Certificate) fact.generateCertificate(new ByteArrayInputStream(Base64.getDecoder().decode(encoded.getBytes())));
     }