Ensure SpEL can compile an expression indexing into a boolean array

Closes gh-32400

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

@@ -245,6 +245,12 @@ public class Indexer extends SpelNodeImpl {
 				}
 				case "B" -> {
 					mv.visitTypeInsn(CHECKCAST, "[B");
+					// byte and boolean arrays are both loaded via BALOAD
+					yield BALOAD;
+				}
+				case "Z" -> {
+					mv.visitTypeInsn(CHECKCAST, "[Z");
+					// byte and boolean arrays are both loaded via BALOAD
 					yield BALOAD;
 				}
 				case "C" -> {

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

@@ -308,6 +308,18 @@ public class SpelCompilationCoverageTests extends AbstractExpressionTests {
 			assertThat(getAst().getExitDescriptor()).isEqualTo("C");
 		}
 
+		@Test
+		void indexIntoPrimitiveBooleanArray() {
+			boolean[] booleans = { true, false };
+
+			expression = parser.parseExpression("[1]");
+
+			assertThat(expression.getValue(booleans)).isEqualTo(false);
+			assertCanCompile(expression);
+			assertThat(expression.getValue(booleans)).isEqualTo(false);
+			assertThat(getAst().getExitDescriptor()).isEqualTo("Z");
+		}
+
 		@Test
 		void indexIntoStringArray() {
 			String[] strings = { "a", "b", "c" };