Introduce constants in LambdaUtils for serialization tests

Author: sstanoje

compiler/src/jdk.internal.vm.compiler/src/org/graalvm/compiler/java/LambdaUtils.java

@@ -55,6 +55,8 @@ public final class LambdaUtils {
     private static final char[] HEX = "0123456789abcdef".toCharArray();
     public static final String LAMBDA_SPLIT_PATTERN;
     public static final String LAMBDA_CLASS_NAME_SUBSTRING;
+    public static final String SERIALIZATION_TEST_LAMBDA_CLASS_SUBSTRING = "$$Lambda";
+    public static final String SERIALIZATION_TEST_LAMBDA_CLASS_SPLIT_PATTERN = "\\$\\$Lambda";
 
     static {
         if (Runtime.version().feature() < 21) {

substratevm/src/com.oracle.svm.hosted/src/com/oracle/svm/hosted/snippets/SubstrateGraphBuilderPlugins.java

@@ -322,9 +322,9 @@ private static void parsePatternAndRegister(String pattern) {
                     // Pattern is a classname (possibly empty) with a trailing wildcard
                     final String className = p.substring(poffset, nameLen - 1);
                     if (!negate) {
-                        if (className.endsWith("$$Lambda")) {
+                        if (className.endsWith(LambdaUtils.SERIALIZATION_TEST_LAMBDA_CLASS_SUBSTRING)) {
                             try {
-                                String lambdaHolderName = className.split(LambdaUtils.LAMBDA_SPLIT_PATTERN)[0];
+                                String lambdaHolderName = className.split(LambdaUtils.SERIALIZATION_TEST_LAMBDA_CLASS_SPLIT_PATTERN)[0];
                                 RuntimeSerialization.registerLambdaCapturingClass(Class.forName(lambdaHolderName, false, Thread.currentThread().getContextClassLoader()));
                             } catch (ClassNotFoundException e) {
                                 // no class, no registration