Change max regex length in SpEL expressions to 1000

This commit changes the max regex length in SpEL expressions from 1024
to 1000 in order to consistently use "round" numbers for recently
introduced limits.

See gh-30265

spring-expression/src/main/java/org/springframework/expression/spel/ast/OperatorMatches.java

@@ -47,7 +47,7 @@ public class OperatorMatches extends Operator {
 	 * Maximum number of characters permitted in a regular expression.
 	 * @since 5.2.23
 	 */
-	private static final int MAX_REGEX_LENGTH = 256;
+	private static final int MAX_REGEX_LENGTH = 1000;
 
 	private final ConcurrentMap<String, Pattern> patternCache;
 

spring-expression/src/test/java/org/springframework/expression/spel/EvaluationTests.java

@@ -201,18 +201,24 @@ void matchesWithPatternAccessThreshold() {
 
 	@Test
 	void matchesWithPatternLengthThreshold() {
-		String pattern = "(0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789" +
-				"0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789" +
-				"01234567890123456789012345678901234567890123456789|abc)";
-		assertThat(pattern).hasSize(256);
-		Expression expr = parser.parseExpression("'abc' matches '" + pattern + "'");
+		String pattern = String.format("^(%s|X)", repeat("12345", 199));
+		assertThat(pattern).hasSize(1000);
+		Expression expr = parser.parseExpression("'X' matches '" + pattern + "'");
 		assertThat(expr.getValue(context, Boolean.class)).isTrue();
 
 		pattern += "?";
-		assertThat(pattern).hasSize(257);
+		assertThat(pattern).hasSize(1001);
 		evaluateAndCheckError("'abc' matches '" + pattern + "'", Boolean.class, SpelMessage.MAX_REGEX_LENGTH_EXCEEDED);
 	}
 
+	private String repeat(String str, int count) {
+		String result = "";
+		for (int i = 0; i < count; i++) {
+			result += str;
+		}
+		return result;
+	}
+
 	// mixing operators
 	@Test
 	public void testMixingOperators01() {