How to use a property in spring data #Query - spring

I can't manage to inject a property from application.yml to a spring data #Query.
The following results in an EL1008E error:
public interface MyRepository extends JpaRepository<MyEntity, Long> {
#Query("select e from MyEntity e where e.foo = :foo and e.env= ?#{env}")
MyEntity findByFoo(#Param("foo") String foo);
}
According to this blog it is possible to inject a property of spring's principal, which is not very different from what I would like to do.
Any hints on this?

I should really stop asking questions and answer them by myself shortly after ... That is not on purpose.
The mentioned blog has the solution included. Add this:
public class PropertyEvaluationContextExtension extends EvaluationContextExtensionSupport {
private final MyProps p;
public PropertyEvaluationContextExtension(final MyProps p) {
this.p= p;
}
#Override
public String getExtensionId() {
return "foo";
}
#Override
public MyProps getRootObject() {
return this.p;
}
}
#Configuration
public class PropertyConfig {
private final MyProps p;
public PropertyConfig(final MyProps p) {
this.p= p;
}
#Bean
EvaluationContextExtensionSupport propertyExtension() {
return new PropertyEvaluationContextExtension(p);
}
}
Now every property of MyProps is accessible via SpEL.

Related

Inversion of control based on properties file

Below is my interface :-
interface Student {
findById();
}
Below are my 2 implementations of interface :-
class Matriculation implements Student {
findById(){
//implementation
}
}
class Graduation implements Student {
findById(){
//implementation
}
}
application.properties
graduation=true
Calling class :-
class Test {
#Autowired
Student student ;
method(){
student.findById();
}
}
If graduation is true i want to call Graduation class findById else i want to call Matriculation findById method .How can i achieve this in SpringBoot?
you can use the #ConditionalOnProperty annotation. Like this:
#ConditionalOnProperty(name = "graduation", havingValue = "true")
#Service
public class Graduation implements Student
{
#Override
public String findById()
{
return "Graduation";
}
}
correctly indicated in comments, here is a possible implementation.
class Test {
#Autowired
Matriculation matriculationStudent ;
#Autowired
Graduation graduationStudent;
#Value("${graduation}")
private boolean graduation;
void method(){
if (graduation) {
graduationStudent.findById();
} else {
matriculationStudent.findById();
}
}
}
You're gonna create a Spring Component like this:
#Component
public class StudentFactory {
#Autowired
private Matriculation matriculation;
#Autowired
private Graduation graduation;
#Value("${graduation}")
private boolean graduationValue;
public Student getImplementation() {
if (graduationValue) {
return graduation;
} else {
return matriculation;
}
}
}
and then you just inject the factory in the Test class and call getImplementation method

Custom Source presence checking method name in MapStruct

is it posible to generate a custom "presence checking" method name, being a method of the property itself rather the owning object?
I know I can use hasProperty() methods to check for presence of a value...
https://mapstruct.org/documentation/stable/reference/html/#source-presence-check
but with Optional or JsonNullable (from OpenApi nonullable) that checking method is on the property itself, not on the owning object... :-(
I can map JsonNullable or Optional easyly 'using' or extending a simple custom Mapper
#Mapper
public class JsonNullableMapper {
public <T> T fromJsonNullable(final JsonNullable<T> jsonNullable) {
return jsonNullable.orElse(null);
}
public <T> JsonNullable<T> asJsonNullable(final T nullable) {
return nullable != null ? JsonNullable.of(nullable) : JsonNullable.undefined();
}
}
what I would like to achieve is something like this as "presence check":
if(source.getProperty().isPresent()) {
target.set(customMapper.map(source.getProperty()));
}
Any one found a solution for this?
Thanks and regards
I have managed to implement custom lombok extension which generates "presence checknig" methods.
Here is an example project. In short I added #PresenceChecker annotation and implemented Lombok Javac Annotation handler.
It's possible to use it together with other Lombok annotations:
#Getter
#Setter
public class User {
private String name;
}
#Getter
#Setter
#PresenceChecker
public class UserUpdateDto {
private String name;
}
//MapStruct Mapper interface declaration
#Mapper
public interface UserMapper {
void updateUser(UserUpdateDto dto, #MappingTarget User user);
}
Generated code:
public class User {
private String name;
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
}
public class UserUpdateDto {
private boolean hasName;
private String name;
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
this.hasName = true;
}
public boolean hasName() {
return this.hasName;
}
}
//MapStruct Mapper implementation
public class UserMapperImpl implements UserMapper {
#Override
public void updateUser(UserUpdateDto dto, User user) {
if ( dto == null ) {
return;
}
if ( dto.hasName() ) {
user.setName( dto.getName() );
}
}
}
The answer is unfortunately a straight no.
It is not possible in the current version of MapStruct (1.3.1final) and its not on the shortlist for 1.4.0. You could open up an issue on the git repo of MapStruct as feature request.

How can I load propeties in a Map with SpringBoot?

I try to initialize a Map in my SpringBoot application but I am doing something wrong.
My config.properties:
myFieldMap.10000.fieldName=MyFieldName
myFieldMap.10000.fieldName2=MyFieldName2
myFieldMap.10001.fieldName=MyFieldName
myFieldMap.10001.fieldName2=MyFieldName2
myFieldMap.10002.fieldName=MyFieldName
myFieldMap.10003.fieldName2=MyFieldName2
...
(Isn't it possible to use some kind of bracket notation like myFieldMap[10001].fieldName for maps (I saw it used for lists).
I tried with my MyConfig.class:
#PropertySource("classpath:config.properties")
#Component
public class MyConfig {
private java.util.Map<Integer, MyMapping> theMappingsMap = new HashMap<Integer, MyMapping>();
public Map<String, MyMapping> getTheMappingsMap() {
return theMappingsMap;
}
public void setTheMappingsMap(Map<String, MyMapping> theMappingsMap) {
this.theMappingsMap= theMappingsMap;
}
public class MyMapping {
private String fieldName;
private String fieldName2;
public String getFieldName() {
return fieldName;
}
public String getFieldName2() {
return fieldName2;
}
public void setFieldName(final String fieldName) {
this.fieldName = fieldName;
}
public void setFieldName2(final String fieldName) {
this.fieldName2 = fieldName;
}
}
}
How do I have to adapt my code to let SpringBoot initialize my configuration (Map) with the definitions in the config.properties file?
You are missing #ConfigurationProperties annotation. Try this
#PropertySource("classpath:config.properties")
#Configuration
#ConfigurationProperties
public class MyConfig {
private java.util.Map<String, MyMapping> myFieldMap = new HashMap<>();
....
}
Another issue with your code is, if you want to make MyMapping class as an inner class of MyConfig, then you need to declare it as static. Or else you can make it as a separate class.

Spring Data Rest Repository with abstract class / inheritance

I can't get Spring Data Rest with class inheritance working.
I'd like to have a single JSON Endpoint which handles all my concrete classes.
Repo:
public interface AbstractFooRepo extends KeyValueRepository<AbstractFoo, String> {}
Abstract class:
#JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "type")
#JsonSubTypes({
#JsonSubTypes.Type(value = MyFoo.class, name = "MY_FOO")
})
public abstract class AbstractFoo {
#Id public String id;
public String type;
}
Concrete class:
public class MyFoo extends AbstractFoo { }
Now when calling POST /abstractFoos with {"type":"MY_FOO"}, it tells me: java.lang.IllegalArgumentException: PersistentEntity must not be null!.
This seems to happen, because Spring doesn't know about MyFoo.
Is there some way to tell Spring Data REST about MyFoo without creating a Repository and a REST Endpoint for it?
(I'm using Spring Boot 1.5.1 and Spring Data REST 2.6.0)
EDIT:
Application.java:
#SpringBootApplication
#EnableMapRepositories
public class Application {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
I'm using Spring Boot 1.5.1 and Spring Data Release Ingalls.
KeyValueRepository doesn't work with inheritance. It uses the class name of every saved object to find the corresponding key-value-store. E.g. save(new Foo()) will place the saved object within the Foo collection. And abstractFoosRepo.findAll() will look within the AbstractFoo collection and won't find any Foo object.
Here's the working code using MongoRepository:
Application.java
Default Spring Boot Application Starter.
#SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
AbstractFoo.java
I've tested include = JsonTypeInfo.As.EXISTING_PROPERTY and include = JsonTypeInfo.As.PROPERTY. Both seem to work fine!
It's even possible to register the Jackson SubTypes with a custom JacksonModule.
IMPORTANT: #RestResource(path="abstractFoos") is highly recommended. Else the _links.self links will point to /foos and /bars instead of /abstractFoos.
#JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.EXISTING_PROPERTY, property = "type")
#JsonSubTypes({
#JsonSubTypes.Type(value = Foo.class, name = "MY_FOO"),
#JsonSubTypes.Type(value = Bar.class, name = "MY_Bar")
})
#Document(collection="foo_collection")
#RestResource(path="abstractFoos")
public abstract class AbstractFoo {
#Id public String id;
public abstract String getType();
}
AbstractFooRepo.java
Nothing special here
public interface AbstractFooRepo extends MongoRepository<AbstractFoo, String> { }
Foo.java & Bar.java
#Persistent
public class Foo extends AbstractFoo {
#Override
public String getType() {
return "MY_FOO";
}
}
#Persistent
public class Bar extends AbstractFoo {
#Override
public String getType() {
return "MY_BAR";
}
}
FooRelProvider.java
Without this part, the output of the objects would be separated in two arrays under _embedded.foos and _embedded.bars.
The supports method ensures that for all classes which extend AbstractFoo, the objects will be placed within _embedded.abstractFoos.
#Component
#Order(Ordered.HIGHEST_PRECEDENCE)
public class FooRelProvider extends EvoInflectorRelProvider {
#Override
public String getCollectionResourceRelFor(final Class<?> type) {
return super.getCollectionResourceRelFor(AbstractFoo.class);
}
#Override
public String getItemResourceRelFor(final Class<?> type) {
return super.getItemResourceRelFor(AbstractFoo.class);
}
#Override
public boolean supports(final Class<?> delimiter) {
return AbstractFoo.class.isAssignableFrom(delimiter);
}
}
EDIT
Added #Persistent to Foo.java and Bar.java. (Adding it to AbstractFoo.java doesn't work). Without this annotation I got NullPointerExceptions when trying to use JSR 303 Validation Annotations within inherited classes.
Example code to reproduce the error:
public class A {
#Id public String id;
#Valid public B b;
// #JsonTypeInfo + #JsonSubTypes
public static abstract class B {
#NotNull public String s;
}
// #Persistent <- Needed!
public static class B1 extends B { }
}
Please see the discussion in this resolved jira task for details of what is currently supported in spring-data-rest regarding JsonTypeInfo. And this jira task on what is still missing.
To summarize - only #JsonTypeInfo with include=JsonTypeInfo.As.EXISTING_PROPERTY is working for serialization and deserialization currently.
Also, you need spring-data-rest 2.5.3 (Hopper SR3) or later to get this limited support.
Please see my sample application - https://github.com/mduesterhoeft/spring-data-rest-entity-inheritance/tree/fixed-hopper-sr3-snapshot
With include=JsonTypeInfo.As.EXISTING_PROPERTY the type information is extracted from a regular property. An example helps getting the point of this way of adding type information:
The abstract class:
#Entity #Inheritance(strategy= SINGLE_TABLE)
#JsonTypeInfo(use=JsonTypeInfo.Id.NAME,
include=JsonTypeInfo.As.EXISTING_PROPERTY,
property="type")
#JsonSubTypes({
#Type(name="DECIMAL", value=DecimalValue.class),
#Type(name="STRING", value=StringValue.class)})
public abstract class Value {
#Id #GeneratedValue(strategy = IDENTITY)
#Getter
private Long id;
public abstract String getType();
}
And the subclass:
#Entity #DiscriminatorValue("D")
#Getter #Setter
public class DecimalValue extends Value {
#Column(name = "DECIMAL_VALUE")
private BigDecimal value;
public String getType() {
return "DECIMAL";
}
}

Spring Boot YML Config Class Inheritance

Is it possible to use inheritance in Spring Boot YML configuration classes? If so, how would that be accomplished?
For example:
#ConfigurationProperties(prefix="my-config")
public class Config {
List<Vehicle> vehicles;
}
And the class (or interface) "Vehicle" has two implementations: Truck and Car. So the YAML might look like:
my.config.vehicles:
-
type: car
seats: 3
-
type: truck
axles: 3
I do not think it is possible (at least not that I know of). You could however design your code as follow:
Inject the properties into a Builder object
Define an object with all properties, which we'll call the VehicleBuilder (or factory, you choose its name).
The VehicleBuilders are injected from the Yaml.
You can then retrieve each builder's vehicle in a #PostConstruct block. The code:
#ConfigurationProperties(prefix="my-config")
#Component
public class Config {
private List<VehicleBuilder> vehicles = new ArrayList<VehicleBuilder>();
private List<Vehicle> concreteVehicles;
public List<VehicleBuilder> getVehicles() {
return vehicles;
}
public List<Vehicle> getConcreteVehicles() {
return concreteVehicles;
}
#PostConstruct
protected void postConstruct(){
concreteVehicles = vehicles.stream().map(f -> f.get())
.collect(Collectors.<Vehicle>toList());
}
}
The builder:
public class VehicleBuilder {
private String type;
private int seats;
private int axles;
public Vehicle get() {
if ("car".equals(type)) {
return new Car(seats);
} else if ("truck".equals(type)) {
return new Trunk(axles);
}
throw new AssertionError();
}
public void setType(String type) {
this.type = type;
}
public void setSeats(int seats) {
this.seats = seats;
}
public void setAxles(int axles) {
this.axles = axles;
}
}

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