Make source code compatible with JDK 8

Closes spring-projectsgh-10695

Author: marcusdacoregio

build.gradle

@@ -105,6 +105,7 @@ subprojects {
 	tasks.withType(JavaCompile) {
 		options.encoding = "UTF-8"
 		options.compilerArgs.add("-parameters")
+		options.release = 8
 	}
 }
 

config/src/main/java/org/springframework/security/config/annotation/web/configurers/oauth2/server/resource/OAuth2ResourceServerConfigurer.java

@@ -18,6 +18,7 @@
 
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.function.Supplier;
@@ -27,6 +28,7 @@
 import org.springframework.context.ApplicationContext;
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.http.MediaType;
+import org.springframework.security.access.AccessDeniedException;
 import org.springframework.security.authentication.AbstractAuthenticationToken;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.authentication.AuthenticationManagerResolver;
@@ -159,13 +161,18 @@ public final class OAuth2ResourceServerConfigurer<H extends HttpSecurityBuilder<
 	private OpaqueTokenConfigurer opaqueTokenConfigurer;
 
 	private AccessDeniedHandler accessDeniedHandler = new DelegatingAccessDeniedHandler(
-			new LinkedHashMap<>(Map.of(CsrfException.class, new AccessDeniedHandlerImpl())),
-			new BearerTokenAccessDeniedHandler());
+			new LinkedHashMap<>(createAccessDeniedHandlers()), new BearerTokenAccessDeniedHandler());
 
 	private AuthenticationEntryPoint authenticationEntryPoint = new BearerTokenAuthenticationEntryPoint();
 
 	private BearerTokenRequestMatcher requestMatcher = new BearerTokenRequestMatcher();
 
+	private static Map<Class<? extends AccessDeniedException>, AccessDeniedHandler> createAccessDeniedHandlers() {
+		Map<Class<? extends AccessDeniedException>, AccessDeniedHandler> handlers = new HashMap<>();
+		handlers.put(CsrfException.class, new AccessDeniedHandlerImpl());
+		return handlers;
+	}
+
 	public OAuth2ResourceServerConfigurer(ApplicationContext context) {
 		Assert.notNull(context, "context cannot be null");
 		this.context = context;

config/src/main/java/org/springframework/security/config/annotation/web/configurers/saml2/Saml2LoginConfigurer.java

@@ -297,8 +297,7 @@ private String version() {
 		if (version != null) {
 			return version;
 		}
-		return Version.class.getModule().getDescriptor().version().map(Object::toString)
-				.orElseThrow(() -> new IllegalStateException("cannot determine OpenSAML version"));
+		return Version.getVersion();
 	}
 
 	private void registerDefaultAuthenticationProvider(B http) {

config/src/main/java/org/springframework/security/config/annotation/web/configurers/saml2/Saml2LogoutConfigurer.java

@@ -319,8 +319,7 @@ private String version() {
 		if (version != null) {
 			return version;
 		}
-		return Version.class.getModule().getDescriptor().version().map(Object::toString)
-				.orElseThrow(() -> new IllegalStateException("cannot determine OpenSAML version"));
+		return Version.getVersion();
 	}
 
 	/**

config/src/test/java/org/springframework/security/config/annotation/web/configurers/NamespaceHttpX509Tests.java

@@ -21,11 +21,13 @@
 import java.security.cert.CertificateFactory;
 import java.security.cert.X509Certificate;
 
+import javax.security.auth.x500.X500Principal;
 import javax.servlet.http.HttpServletRequest;
 
+import org.bouncycastle.asn1.x500.X500Name;
+import org.bouncycastle.asn1.x500.style.BCStyle;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
-import sun.security.x509.X500Name;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
@@ -240,12 +242,8 @@ protected void configure(HttpSecurity http) throws Exception {
 		}
 
 		private String extractCommonName(X509Certificate certificate) {
-			try {
-				return ((X500Name) certificate.getSubjectDN()).getCommonName();
-			}
-			catch (Exception ex) {
-				throw new IllegalArgumentException(ex);
-			}
+			X500Principal principal = certificate.getSubjectX500Principal();
+			return new X500Name(principal.getName()).getRDNs(BCStyle.CN)[0].getFirst().getValue().toString();
 		}
 
 	}

core/src/test/java/org/springframework/security/core/SpringSecurityCoreVersionTests.java

@@ -18,6 +18,7 @@
 
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -60,15 +61,24 @@ public class SpringSecurityCoreVersionTests {
 
 	@BeforeEach
 	public void setup() throws Exception {
-		Field logger = ReflectionUtils.findField(SpringSecurityCoreVersion.class, "logger");
-		StaticFinalReflectionUtils.setField(logger, this.logger);
+		setFinalStaticField(SpringSecurityCoreVersion.class, "logger", this.logger);
 	}
 
 	@AfterEach
 	public void cleanup() throws Exception {
 		System.clearProperty(getDisableChecksProperty());
-		Field logger = ReflectionUtils.findField(SpringSecurityCoreVersion.class, "logger");
-		StaticFinalReflectionUtils.setField(logger, LogFactory.getLog(SpringSecurityCoreVersion.class));
+		setFinalStaticField(SpringSecurityCoreVersion.class, "logger",
+				LogFactory.getLog(SpringSecurityCoreVersion.class));
+	}
+
+	private static void setFinalStaticField(Class<?> clazz, String fieldName, Object value)
+			throws ReflectiveOperationException {
+		Field field = clazz.getDeclaredField(fieldName);
+		field.setAccessible(true);
+		Field modifiers = Field.class.getDeclaredField("modifiers");
+		modifiers.setAccessible(true);
+		modifiers.setInt(field, field.getModifiers() & ~Modifier.FINAL);
+		field.set(null, value);
 	}
 
 	@Test