Properly handle CAST functions on HQL.

See #3024

Author: gregturn

spring-data-jpa/src/main/antlr4/org/springframework/data/jpa/repository/query/Hql.g4

@@ -492,9 +492,18 @@ frameEnd
 
 // https://docs.jboss.org/hibernate/orm/6.1/userguide/html_single/Hibernate_User_Guide.html#hql-functions
 castFunction
-    : CAST '(' expression AS identifier ')'
+    : CAST '(' expression AS castTarget ')'
     ;
 
+castTarget
+	: castTargetType ('(' INTEGER_LITERAL (',' INTEGER_LITERAL)? ')')?
+	;
+
+castTargetType
+	returns [String fullTargetName]
+	: (i=identifier { $fullTargetName = _localctx.i.getText(); }) ('.' c=identifier { $fullTargetName += ("." + _localctx.c.getText() ); })*
+	;
+
 extractFunction
     : EXTRACT '(' expression FROM expression ')'
     | dateTimeFunction '(' expression ')'

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/HqlQueryRenderer.java

@@ -106,7 +106,7 @@ public List<JpaQueryParsingToken> visitCte(HqlParser.CteContext ctx) {
 		if (ctx.MATERIALIZED() != null) {
 			tokens.add(TOKEN_MATERIALIZED);
 		}
-		
+
 		tokens.add(TOKEN_OPEN_PAREN);
 		tokens.addAll(visit(ctx.queryExpression()));
 		tokens.add(TOKEN_CLOSE_PAREN);
@@ -1790,16 +1790,47 @@ public List<JpaQueryParsingToken> visitCastFunction(HqlParser.CastFunctionContex
 
 		List<JpaQueryParsingToken> tokens = new ArrayList<>();
 
-		tokens.add(new JpaQueryParsingToken(ctx.CAST()));
+		tokens.add(new JpaQueryParsingToken(ctx.CAST(), false));
 		tokens.add(TOKEN_OPEN_PAREN);
 		tokens.addAll(visit(ctx.expression()));
 		tokens.add(new JpaQueryParsingToken(ctx.AS()));
-		tokens.addAll(visit(ctx.identifier()));
+		tokens.addAll(visit(ctx.castTarget()));
+		NOSPACE(tokens);
 		tokens.add(TOKEN_CLOSE_PAREN);
 
 		return tokens;
 	}
 
+	@Override
+	public List<JpaQueryParsingToken> visitCastTarget(HqlParser.CastTargetContext ctx) {
+
+		List<JpaQueryParsingToken> tokens = new ArrayList<>();
+
+		tokens.addAll(visit(ctx.castTargetType()));
+
+		if (ctx.INTEGER_LITERAL() != null && !ctx.INTEGER_LITERAL().isEmpty()) {
+
+			tokens.add(TOKEN_OPEN_PAREN);
+
+			ctx.INTEGER_LITERAL().forEach(terminalNode -> {
+
+				tokens.add(new JpaQueryParsingToken(terminalNode));
+				tokens.add(TOKEN_COMMA);
+			});
+			CLIP(tokens);
+			NOSPACE(tokens);
+
+			tokens.add(TOKEN_CLOSE_PAREN);
+		}
+
+		return tokens;
+	}
+
+	@Override
+	public List<JpaQueryParsingToken> visitCastTargetType(HqlParser.CastTargetTypeContext ctx) {
+		return List.of(new JpaQueryParsingToken(ctx.fullTargetName));
+	}
+
 	@Override
 	public List<JpaQueryParsingToken> visitExtractFunction(HqlParser.ExtractFunctionContext ctx) {
 

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/HqlQueryRendererTests.java

@@ -1521,4 +1521,9 @@ void floorShouldBeValidEntityName() {
 	void queryWithSignShouldWork() {
 		assertQuery("select t.sign from TestEntity t");
 	}
+
+	@Test // GH-3024
+	void castFunctionWithFqdnShouldWork() {
+		assertQuery("SELECT o FROM Order o WHERE CAST(:userId AS java.util.UUID) IS NULL OR o.user.id = :userId");
+	}
 }