DATAJPA-1519 - Final polishing.

Introduced dedicated JPA SpEL root  object to be able to explicitly control the function names exposed.

src/main/java/org/springframework/data/jpa/repository/query/EscapeCharacter.java

@@ -34,30 +34,20 @@ public class EscapeCharacter {
 
 	private static final List<String> TO_REPLACE = Arrays.asList("_", "%");
 
-	char value;
+	char escapeCharacter;
 
 	/**
 	 * Escapes all special like characters ({@code _}, {@code %}) using the configured escape character.
 	 *
-	 * @param value May be {@literal null}.
+	 * @param value may be {@literal null}.
 	 * @return
 	 */
 	@Nullable
 	public String escape(String value) {
 
-		if (value == null) {
-			return null;
-		}
-		return TO_REPLACE.stream() //
-				.reduce(value, (it, character) -> it.replace(character, this.value + character));
-	}
-
-	/**
-	 * Makes the underlying character available.
-	 *
-	 * @return the value
-	 */
-	public char escapeCharacter() {
-		return value;
+		return value == null //
+				? null //
+				: TO_REPLACE.stream() //
+						.reduce(value, (it, character) -> it.replace(character, this.escapeCharacter + character));
 	}
 }

src/main/java/org/springframework/data/jpa/repository/query/JpaQueryCreator.java

@@ -291,7 +291,7 @@ public class JpaQueryCreator extends AbstractQueryCreator<CriteriaQuery<? extend
 					Expression<String> stringPath = getTypedPath(root, part);
 					Expression<String> propertyExpression = upperIfIgnoreCase(stringPath);
 					Expression<String> parameterExpression = upperIfIgnoreCase(provider.next(part, String.class).getExpression());
-					Predicate like = builder.like(propertyExpression, parameterExpression, escape.getValue());
+					Predicate like = builder.like(propertyExpression, parameterExpression, escape.getEscapeCharacter());
 					return type.equals(NOT_LIKE) || type.equals(NOT_CONTAINING) ? like.not() : like;
 				case TRUE:
 					Expression<Boolean> truePath = getTypedPath(root, part);

src/main/java/org/springframework/data/jpa/repository/support/JpaEvaluationContextExtension.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.jpa.repository.support;
 
+import lombok.RequiredArgsConstructor;
+
 import org.springframework.data.jpa.repository.query.EscapeCharacter;
 import org.springframework.data.spel.spi.EvaluationContextExtension;
 
@@ -26,7 +28,7 @@ import org.springframework.data.spel.spi.EvaluationContextExtension;
  */
 public class JpaEvaluationContextExtension implements EvaluationContextExtension {
 
-	private final EscapeCharacter character;
+	private final JpaRootObject root;
 
 	/**
 	 * Creates a new {@link JpaEvaluationContextExtension} for the given escape character.
@@ -34,7 +36,7 @@ public class JpaEvaluationContextExtension implements EvaluationContextExtension
 	 * @param escapeCharacter the character to be used to escape parameters for LIKE expression.
 	 */
 	public JpaEvaluationContextExtension(char escapeCharacter) {
-		this.character = EscapeCharacter.of(escapeCharacter);
+		this.root = JpaRootObject.of(EscapeCharacter.of(escapeCharacter));
 	}
 
 	/*
@@ -52,6 +54,32 @@ public class JpaEvaluationContextExtension implements EvaluationContextExtension
 	 */
 	@Override
 	public Object getRootObject() {
-		return character;
+		return root;
+	}
+
+	@RequiredArgsConstructor(staticName = "of")
+	public static class JpaRootObject {
+
+		private final EscapeCharacter character;
+
+		/**
+		 * Escapes the given source {@link String} for LIKE expressions.
+		 *
+		 * @param source can be {@literal null}.
+		 * @return
+		 * @see EscapeCharacter#escape(String)
+		 */
+		public String escape(String source) {
+			return character.escape(source);
+		}
+
+		/**
+		 * Returns the escape character being used to escape special characters for LIKE expressions.
+		 *
+		 * @return
+		 */
+		public char escapeCharacter() {
+			return character.getEscapeCharacter();
+		}
 	}
 }