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.
Related
I went through the link: How to pass a Map<String, String> with application.properties and other related links multiple times, but still its not working.
I'm using Spring Boot and Spring REST example. Link Question: How to by default execute the latest version of endpoint in Spring Boot REST?.
I've created mapping something like this and simply read the mapping
get.customers={GET: '/app-data/customers', VERSION: 'v1'}
post.customers={POST: '/app-data/customers', VERSION: 'v1'}
get.customers.custId={GET: '/app-data/customers/{custId}', VERSION: 'v2'}
Code:
private String resolveLastVersion() {
// read from configuration or something
return "2";
}
Code:
#Component
#ConfigurationProperties
#PropertySource("classpath:restendpoint.properties")
public class PriorityProcessor {
private final Map<String, String> priorityMap = new HashMap<>();
public Map<String, String> getPriority() {
return priorityMap;
}
}
Code:
I suggest the following implementation:
#ConfigurationProperties(prefix="request")
public class ConfigurationProps {
private List<Mapping> mapping;
public List<Mapping> getMapping() {
return mapping;
}
public void setMapping(List<Mapping> mapping) {
this.mapping = mapping;
}
}
Class Mapping will denote the information about the single mapping:
public class Mapping {
private String method;
private String url;
private String version;
public Mapping(String method, String url, String version) {
this.method = method;
this.url = url;
this.version = version;
}
public Mapping() {
}
// getters setters here
}
On the Configuration or spring boot application class (the one with main method):
#EnableConfigurationProperties(ConfigurationProps.class)
In the properties file put:
request.mapping[0].method=get
request.mapping[0].url=/customers
request.mapping[0].version=1
request.mapping[1].method=post
request.mapping[1].url=/students
request.mapping[1].version=2
In Filter (I assume you followed my suggestion from the linked question):
#Component
#Order(1)
public class LatestVersionFilter implements Filter {
private List<Mapping> mappings;
public LatestVersionFilter(ConfigurationProps props) {
this.mappings = props.getMapping();
}
}
I have a class which is composed of 2 different objects :
public class MyClass{
private OptionClass optionClass;
private ConstantClass constantClass;
public DocumentToSignRestRequest(OptionClass optionClass, ConstantClass constantClass) {
this.optionClass= optionClass;
this.constantClass= constantClass;
}
}
My first class is a classic POJO. My second class retrieve values from the application.properties file.
public class ConstantClass {
#Value("${api.url}")
private String hostName;
#Value("${sign.path}")
private String pathStart;
public ConstantClass () {
this.hostName= getHostName();
this.path = getPath();
}
I map MyClass with MyClassDto in order to call a service.
#PostMapping(
value="/sign",
consumes = { MediaType.APPLICATION_XML_VALUE, MediaType.APPLICATION_JSON_VALUE },
produces = { MediaType.APPLICATION_XML_VALUE, MediaType.APPLICATION_JSON_VALUE }
)
public MyClassRest prepareDocument(#RequestBody DocumentToPrepare documentToPrepare) throws Exception {
MyClassRest returnValue = new MyClassRest ();
ModelMapper modelMapper = new ModelMapper();
MyClassDto myClassDto = modelMapper.map(documentToPrepare, MyClassDto .class);
DocumentDto signedDocument = documentService.signDocument(documentDto);
returnValue = modelMapper.map(signedDocument, DocumentRest.class);
return returnValue;
}
My DTO class work fine and retrieve the OptionClass datas, but concerning the second Class, i obtain null as value, while i try to print it out in the service layer.
Your ConstantClass should be a Bean or a Component (as #cassiomolin says in comments)
#Component
public class ConstantClass {
private String hostName;
private String pathStart;
public ConstantClass (#Value("${api.url}") String url, #Value("${sign.path}") String path ) {
this.hostName = url;
this.pathStart = path;
}
// getters...
Then you can easily inject this component in your Controller and use it.
#Controller
public class YourController(){
private ConstantClass constantClass;
public YourController(ConstantClass constantClass){
this.constantClass = constantClass;
}
#PostMapping("...")
public MyClass post(.....){
.....
MyClass myclass = new MyClass(this.constantClass,...)
.....
}
}
note that Spring can autowire #Value and #Component, ... via the constructor; that can be very useful when you do unit-testing
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.
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;
}
}
Here is my ConfigUpdater class
private final class ConfigUpdater implements ManagedService {
#SuppressWarnings("rawtypes")
#Override
public void updated(Dictionary config) throws ConfigurationException {
if (config == null) {
return;
}
String title = ((String)config.get("title"));
}
}
My question is how can I access String title in any other class? Or how can I get config dictionary in any other class... Method updated will only be called when a config file is changed... once it is changed how can access its data in other class?
In general you would create a service that exposes these properties to other components.
For example, you could give your ConfigUpdater a second interface. Another component can than lookup/inject this interface from the service registry and use it's methods to access the properties.
I created an example project on GitHub: https://github.com/paulbakker/configuration-example
The most important part is the service that implements both ManagedService and a custom interface:
#Component(properties=#Property(name=Constants.SERVICE_PID, value="example.configurationservice"))
public class ConfigurationUpdater implements ManagedService, MyConfiguration{
private volatile String message;
#Override
public void updated(#SuppressWarnings("rawtypes") Dictionary properties) throws ConfigurationException {
message = (String)properties.get("message");
}
#Override
public String getMessage() {
return message;
}
}
The configuration can then be used like this:
#Component(provides=ExampleConsumer.class,
properties= {
#Property(name = CommandProcessor.COMMAND_SCOPE, value = "example"),
#Property(name = CommandProcessor.COMMAND_FUNCTION, values = {"showMessage"}) })
public class ExampleConsumer {
#ServiceDependency
private volatile MyConfiguration config;
public void showMessage() {
String message = config.getMessage();
System.out.println(message);
}
}