DATAJPA-218 - Use true is true predicate if probe yields to empty criteria.

Author: mp911de

src/main/java/org/springframework/data/jpa/convert/QueryByExamplePredicateBuilder.java

@@ -82,7 +82,7 @@ public static <T> Predicate getPredicate(Root<T> root, CriteriaBuilder cb, Examp
 				new PathNode("root", null, example.getProbe()));
 
 		if (predicates.isEmpty()) {
-			return cb.isTrue(cb.literal(false));
+			return cb.isTrue(cb.literal(true));
 		}
 
 		if (predicates.size() == 1) {

src/test/java/org/springframework/data/jpa/convert/QueryByExamplePredicateBuilderUnitTests.java

@@ -56,7 +56,7 @@ public class QueryByExamplePredicateBuilderUnitTests {
 	@Mock Root root;
 	@Mock EntityType<Person> personEntityType;
 	@Mock Expression expressionMock;
-	@Mock Predicate falsePredicate;
+	@Mock Predicate truePredicate;
 	@Mock Predicate dummyPredicate;
 	@Mock Predicate listPredicate;
 	@Mock Path dummyPath;
@@ -101,7 +101,7 @@ public void setUp() {
 		when(cb.like(any(Expression.class), any(String.class))).thenReturn(dummyPredicate);
 
 		when(cb.literal(any(Boolean.class))).thenReturn(expressionMock);
-		when(cb.isTrue(eq(expressionMock))).thenReturn(falsePredicate);
+		when(cb.isTrue(eq(expressionMock))).thenReturn(truePredicate);
 		when(cb.and(Matchers.<Predicate> anyVararg())).thenReturn(listPredicate);
 	}
 
@@ -133,8 +133,8 @@ public void getPredicateShouldThrowExceptionOnNullExample() {
 	 * @see DATAJPA-218
 	 */
 	@Test
-	public void emptyCriteriaListShouldResultFalsePredicate() {
-		assertThat(QueryByExamplePredicateBuilder.getPredicate(root, cb, of(new Person())), equalTo(falsePredicate));
+	public void emptyCriteriaListShouldResultTruePredicate() {
+		assertThat(QueryByExamplePredicateBuilder.getPredicate(root, cb, of(new Person())), equalTo(truePredicate));
 	}
 
 	/**

src/test/java/org/springframework/data/jpa/repository/UserRepositoryTests.java

@@ -1997,6 +1997,23 @@ public void findAllByExample() {
 		assertThat(users.get(0), is(firstUser));
 	}
 
+	/**
+	 * @see DATAJPA-218
+	 */
+	@Test
+	public void findAllByExampleWithEmptyProbe() {
+
+		flushTestUsers();
+
+		User prototype = new User();
+		prototype.setCreatedAt(null);
+
+		List<User> users = repository
+				.findAll(of(prototype, ExampleSpec.untyped().withIgnorePaths("age", "createdAt", "active")));
+
+		assertThat(users, hasSize(4));
+	}
+
 	/**
 	 * @see DATAJPA-218
 	 */