In the property file (config.properties) I defined several properties:
my.property.first=xyz
my.property.second=12
I created a class to read these properties:
package my.package.first;
............
#Configuration
public Class MyProperties {
#Value("${my.property.first}") private String propertyFirst;
#Value ("${my.property.second}") private String propertySecond;
public String getPropertyFirst() {
return propertyFirst;
}
public int getPropertySecond() {
return propertySecond
}
#Bean
public MyProperties getInstance() {
return this;
}
}
Now I want to use these properties in a class placed in some other package:
package my.otherpackage.third;
import my.property.package.first.MyProperties;
.............................
public class GetMyProperties{
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(MyProperties.class);
MyProperties myProperties =context.getBean("getInstance",MyProperties.class);
//This returns ${my.property.first}
String propertyFirst = myProperties.getPropertyFirst();
// This returns ${my.property.second}
int propertySecond = context.getBeanFactory().resolveEmbeddedValue(("${my.property.first}"));
}
I try to solve this by using only Annotations.
I use Spring 4.
Thanks
MyProperties isn't really a #Configuration class, it is a bean. Give it the annotation #Component and move the #Bean declaration to another #Configuration class. It doesn't matter where the bean is defined for spring (as long as it is in a configuration class), it'll pick it up if you have the #ComponentScan or #SpringBootApplication somewhere in your app, which I'm pretty sure you do. your MyProperties class you make #Component
You'll want:
#Component
public class MyProperties {
#Value("${my.property.first}") private String propertyFirst;
#Value ("${my.property.second}") private String propertySecond;
public String getPropertyFirst() {
return propertyFirst;
}
public void setPropertyFirst(String propertyFirst){
this.propertyFirst = propertyFirst;
}
public int getPropertySecond() {
return propertySecond
}
public void setPropertySecond(String propertySecond){
this.propertySecond= propertySecond;
}
}
#Configuration
public class Config {
#Bean
public MyProperties getInstance() {
return new MyProperties();
}
}
package my.otherpackage.third;
import my.property.package.first.MyProperties;
.....
#EnableAutoConfiguration
#ComponentScan(basePackages = {"my"})
public class GetMyProperties{
public static void main(String[] args){
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(GetMyProperties.class);
MyProperties myProperties =context.getBean("getInstance",MyProperties.class);
//This returns the value of ${my.property.first}
String propertyFirst = myProperties.getPropertyFirst();
// This returns the value of ${my.property.second}
int propertySecond = myProperties.getPropertySecond();
}
}
Related
I do have ServiceImpl which looks like this:
#Service
#RequiredArgsConstructor
public class ServiceAImpl implements ServiceA {
private final String fieldA;
#Override
public boolean isFieldA(String text){
return fieldA.equals(text);
}
And I would like to inject a field value to fieldA in an Application.java from application.yml like this:
#EnableSwagger2
#SpringBootApplication
public class Application {
#Value("${fieldA}")
private String fieldA;
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public ServiceA serviceA() {
return new ServiceAImpl(fieldA);
}
But I receive the following error when running SpringBoot app:
Error creating bean with name 'serviceAImpl' defined in URLNo qualifying bean of type 'java.lang.String' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
Do you have any solution for that?
You annotated your class with #Service and defined it manually as a bean with the #Bean annotation. I do think the second is the way you planned to use it.
The #Service annotation will make this class get picked up by Spring's component scan and additionally create an instance of it.
Of course it tries to resolve the parameters and fails when it tries to find a matching "bean" for the String field because there is no simple String bean (and should not :) ).
Remove the #Service annotation and everything should work as expected.
Try this
#Service
public class ServiceAImpl implements ServiceA {
private final String fieldA;
#Autowire
public ServiceAImpl(#Value("${fieldA}") String fieldA){
this.fieldA = fieldA;
}
#Override
public boolean isFieldA(String text){
return fieldA.equals(text);
}
}
and this
#EnableSwagger2
#SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
You should not use #Service and #Bean for the same class!
Spring is not so smart :)
You should annotate your bean like:
#RequiredArgsConstructor
public class ServiceAImpl {
#Value("${fieldA}")
private final String something;
...
But I'm not sure it will work with the #RequiredFieldsConstructor, it would be simpler for you write down the constructor annotated with #Autowired and using the #Value annotation for the String parameter:
#Autowired
public ServiceAImpl(#Value("${aProp}") String string) {
You're using two bean declaration mechanisms:
You're registering your bean using #Service
You're registering a bean using #Bean
This means that your service will be created twice. The one defined using #Bean works properly, since it uses the #Value annotation to inject the proper value in your service.
However, the service created due to #Service doesn't know about the #Value annotation and will try to find any bean of type String, which it can't find, and thus it will throw the exception you're seeing.
Now, the solution is to pick either one of these. If you want to keep the #Bean configuration, you should remove the #Service annotation from ServiceAImpl and that will do the trick.
Alternatively, if you want to keep the #Service annotation, you should remove the #Bean declaration, and you should write your own constructor rather than relying on Lombok because this allows you to use the #Value annotation within the constructor:
#Service
public class ServiceAImpl implements ServiceA {
private final String fieldA;
/**
* This constructor works as well
*/
public ServiceAImpl(#Value("${fieldA}") String fieldA) {
this.fieldA = fieldA;
}
#Override
public boolean isFieldA(String text){
return fieldA.equals(text);
}
}
If you want to declare ServiceAImpl as a Spring bean in your Java Configuration file, you should remove the #Service annotation from the class declaration. These annotations doesn't work well together.
ServiceAImpl.java
import org.springframework.beans.factory.annotation.Autowired;
public class ServiceAImpl implements ServiceA {
private final String fieldA;
#Autowired
public ServiceAImpl(String fieldA) {
this.fieldA = fieldA;
}
#Override
public boolean isFieldA(String text) {
return fieldA.equals(text);
}
}
Application.java
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
#SpringBootApplication
public class Application {
#Value("${fieldA}")
private String fieldA;
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public ServiceA serviceA() {
return new ServiceAImpl(fieldA);
}
}
Your application.properties
fieldA=value
The below implementation works well for me. You have two issues, first you have to choose between #Service and #Bean and the other issue I've seen in your code was the #Value annotation, you have to use only to inject a value from the properties.
#SpringBootApplication
public class TestedValueApplication {
#Autowired
void printServiceInstance(ServiceA service) {
System.out.println("Service instance: " + service);
System.out.println("value==value? " + service.isFieldA("value"));
}
public static void main(String[] args) {
SpringApplication.run(TestedValueApplication.class, args);
}
#Bean
public ServiceA serviceA(#Value("${fieldA}") String fieldA) {
return new ServiceAImpl(fieldA);
}
}
Service:
public class ServiceAImpl implements ServiceA {
private String fieldA;
ServiceAImpl(String fieldA) {
this.fieldA = fieldA;
}
public boolean isFieldA(String text) {
return fieldA.equals(text);
}
}
application.properties:
fieldA=value
Assuming you have the following spring configuration:
#Configuration
public class Config {
#Bean
public SomeBean someBean() {
SomeBean someBean = new SomeBean();
someBean.setVar("foobar");
return someBean;
}
}
Then I can use this configuration in some other class for example by importing it with #Import(Config.class). Now, say you don't want to hardcode the string "foobar" but pass it as a parameter to that configuration. How would I do that? It would be nice to create a custom annotation like #FooBarConfiguration(var = "foobar"). Is that possible?
The #Ben answer is the classic and better approach. But if you don't want to use a property file, you can use a #Bean for that. Each #Bean holds a value that you would like to inject.
Full code example:
#SpringBootApplication
public class So49053082Application implements CommandLineRunner {
#Bean
String beanValueFooBar() {
return "fooBar";
}
#Bean
String beanValueBarFoo() {
return "barFoo";
}
private class SomeBean {
private String var;
public void setVar(final String var) {
this.var = var;
}
}
#Configuration
public class Config {
#Bean
public SomeBean someBean(String beanValueBarFoo) {
SomeBean someBean = new SomeBean();
System.out.println(beanValueBarFoo);
someBean.setVar(beanValueBarFoo);
return someBean;
}
}
#Override
public void run(String... args) {
}
public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(So49053082Application.class, args);
context.close();
}
}
Consider using the #Value annotation:
#Configuration
public class Config {
#Value("${myParamValue}")
public String myParam;
#Bean
public SomeBean someBean() {
SomeBean someBean = new SomeBean();
someBean.setVar(myParam);
return someBean;
}
}
you'll need to put the parameters into the environment somehow: there are various techniques using the OS environment, runtime parameters or configuration files, as suits your purposes.
I have that class as you can see below:
#Configuration
#PropertySource("classpath:sample.properties")
public class SampleConfig {
#Value("${attr1.prop}")
private String attr1;
#Value("${attr2.prop}")
private String attr2;
#Bean
public SampleService sampleService() {
return new SampleService(attr1);
}
#Bean
public static PropertySourcesPlaceholderConfigurer placeHolderConfigurer() {
return new PropertySourcesPlaceholderConfigurer();
}
}
I created SampleService bean with parameter attr1. Is possible get access to that properties which I load with #PropertySource later? For example after #Autowired.
Here is code of of using that bean:
#Service
public class SuperHotServiceImpl {
#Autowired
SampleService sammpleService;
public void fooFunc() {
// here I need some magic to get value of attr2.prop
sammpleService.setAttr(attr2);
}
}
Can you tell if it is possible an how? Thanks
If I understand properly your question, then this should help:
#Service
public class SuperHotServiceImpl {
#Autowired
private SampleConfig sammpleConfig;
public void fooFunc() {
System.out.println(sampleConfig.getAttr2());
}
}
Supposed that SampleConfig is annotated as #Component and that you provide the getter.
I have a Spring-Boot-Application as a multimodule-Project in maven. The structure is as follows:
Parent-Project
|--MainApplication
|--Module1
|--ModuleN
In the MainApplication project there is the main() method class annotated with #SpringBootApplication and so on. This project has, as always, an application.properties file which is loaded automatically. So I can access the values with the #Value annotation
#Value("${myapp.api-key}")
private String apiKey;
Within my Module1 I want to use a properties file as well (called module1.properties), where the modules configuration is stored. This File will only be accessed and used in the module. But I cannot get it loaded. I tried it with #Configuration and #PropertySource but no luck.
#Configuration
#PropertySource(value = "classpath:module1.properties")
public class ConfigClass {
How can I load a properties file with Spring-Boot and access the values easily? Could not find a valid solution.
My Configuration
#Configuration
#PropertySource(value = "classpath:tmdb.properties")
public class TMDbConfig {
#Value("${moviedb.tmdb.api-key}")
private String apiKey;
public String getApiKey() {
return apiKey;
}
#Bean
public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {
return new PropertySourcesPlaceholderConfigurer();
}
}
Calling the Config
#Component
public class TMDbWarper {
#Autowired
private TMDbConfig tmdbConfig;
private TmdbApi tmdbApi;
public TMDbWarper(){
tmdbApi = new TmdbApi(tmdbConfig.getApiKey());
}
I'm getting an NullPointerException in the constructor when I autowire the warper.
For field injection:
Fields are injected right after construction of a bean, before any config methods are invoked. Such a config field does not have to be public. Refer Autowired annotation for complete usage. Use constructor injection in this case like below:
#Component
public class TMDbWarper {
private TMDbConfig tmdbConfig;
private TmdbApi tmdbApi;
#Autowired
public TMDbWarper(final TMDbConfig tmdbConfig){
this.tmdbConfig = tmdbConfig;
tmdbApi = new TmdbApi(tmdbConfig.getApiKey());
}
(or)
Use #PostConstruct to initialise like below:
#Component
public class TMDbWarper {
#Autowired
private TMDbConfig tmdbConfig;
private TmdbApi tmdbApi;
#PostConstruct
public void init() {
// any initialisation method
tmdbConfig.getConfig();
}
Autowiring is performed just after the creation of the object(after calling the constructor via reflection). So NullPointerException is expected in your constructor as tmdbConfig field would be null during invocation of constructor
You may fix this by using the #PostConstruct callback method as shown below:
#Component
public class TMDbWarper {
#Autowired
private TMDbConfig tmdbConfig;
private TmdbApi tmdbApi;
public TMDbWarper() {
}
#PostConstruct
public void init() {
tmdbApi = new TmdbApi(tmdbConfig.getApiKey());
}
public TmdbApi getTmdbApi() {
return this.tmdbApi;
}
}
Rest of your configuration seems correct to me.
Hope this helps.
Here is a Spring Boot multi-module example where you can get properties in different module.
Let's say I have main application module, dataparse-module, datasave-module.
StartApp.java in application module:
#SpringBootApplication
public class StartApp {
public static void main(String[] args) {
SpringApplication.run(StartApp.class, args);
}
}
Configuration in dataparse-module. ParseConfig.java:
#Configuration
public class ParseConfig {
#Bean
public XmlParseService xmlParseService() {
return new XmlParseService();
}
}
XmlParseService.java:
#Service
public class XmlParseService {...}
Configuration in datasave-module. SaveConfig.java:
#Configuration
#EnableConfigurationProperties(ServiceProperties.class)
#Import(ParseConfig.class)//get beans from dataparse-module - in this case XmlParseService
public class SaveConfig {
#Bean
public SaveXmlService saveXmlService() {
return new SaveXmlService();
}
}
ServiceProperties.java:
#ConfigurationProperties("datasave")
public class ServiceProperties {
private String message;
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
application.properties in datasave-module in resource/config folder:
datasave.message=Multi-module Maven project!
threads.xml.number=5
file.location.on.disk=D:\temp\registry
Then in datasave-module you can use all your properties either through #Value.
SaveXmlService.java:
#Service
public class SaveXmlService {
#Autowired
XmlParseService xmlParseService;
#Value("${file.location.on.disk: none}")
private String fileLocation;
#Value("${threads.xml.number: 3}")
private int numberOfXmlThreads;
...
}
Or through ServiceProperties:
Service.java:
#Component
public class Service {
#Autowired
ServiceProperties serviceProperties;
public String message() {
return serviceProperties.getMessage();
}
}
I had this situation before, I noticed that the properties file was not copied to the jar.
I made the following to get it working:
In the resources folder, I have created a unique package, then stored my application.properties file inside it. e.g: com/company/project
In the configuration file e.g: TMDBConfig.java I have referenced the full path of my .properties file:
#Configuration
#PropertySource("classpath:/com/company/project/application.properties")
public class AwsConfig
Build and run, it will work like magic.
You could autowire and use the Enviornment bean to read the property
#Configuration
#PropertySource(value = "classpath:tmdb.properties")
public class TMDbConfig {
#Autowired
private Environment env;
public String getApiKey() {
return env.getRequiredProperty("moviedb.tmdb.api-key");
}
}
This should guarantee that property is read from the context when you invoke the getApiKey() method regardless of when the #Value expression is resolved by PropertySourcesPlaceholderConfigurer.
I am trying to get a Spring-boot application going and I am not sure what I am doing wrong here. I have a application.properties file at src/main/resources & src/test/resources. I have an #Bean for my ConfigurationSettings so that I can use them throughout my application:
#Component
public class ConfigurationSettings {
private String product;
private String version;
private String copyright;
private String appName;
private String appDescription;
...
// getters and setters
}
Here is how I kick the application off:
#Configuration
#EnableJpaRepositories
#EnableAutoConfiguration
#EnableConfigurationProperties
#PropertySources(value = {#PropertySource("classpath:application.properties")})
#ComponentScan(basePackages = "com.product")
#EnableScheduling
public class OFAC {
public static void main(String[] args) {
ApplicationContext ctx = SpringApplication.run( OFAC.class, args );
}
And here is my configuration class:
#Configuration
#ComponentScan(basePackages = {"com.product"})
#PropertySources(value = {#PropertySource("classpath:application.properties")})
public class OFAConfiguration {
#Autowired
private Environment env;
#Bean
public ConfigurationSettings configurationSettings() {
ConfigurationSettings configurationSettings = new ConfigurationSettings();
configurationSettings.setAppDescription( env.getRequiredProperty("app.description" ) );
configurationSettings.setAppName( env.getRequiredProperty( "app.name" ) );
configurationSettings.setServerPort( env.getRequiredProperty( "server.port" ) );
return configurationSettings;
}
I am trying to use it in a controller:
#RestController
public class AboutController {
#Autowired
private ConfigurationSettings configurationSettings;
#RequestMapping(value = "/about", method = RequestMethod.GET)
public About index() {
String product = configurationSettings.getProduct();
String version = configurationSettings.getVersion();
String copyright = configurationSettings.getCopyright();
return new About( product, version, copyright );
}
}
However, when step thru this, all the values of ConfigurationSettings are null. I do have a test that successfully loads the values:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = {OFAConfiguration.class})
public class OFAConfigurationTest {
#Autowired
private Environment environment;
#Autowired
private ConfigurationSettings configurationSettings;
#Test
public void testConfigurationLoads() {
assertNotNull(environment);
Assert.assertNotNull(configurationSettings);
}
#Test
public void testConfigurationSettingValues() {
assertEquals("Product Name", configurationSettings.getProduct());
assertEquals("0.0.1", configurationSettings.getVersion());
assertEquals("2014 Product", configurationSettings.getCopyright());
}
Can anyone see why the ConfigurationSettings are not being populated in my Controller?
Your configuration leads to 2 instances of the ConfigurationSettings class and probably one instance overrides the other.
The 'ConfigurationSettings' has the #Component annotation as you are scanning for components (#ComponentScan) this will lead to an instance. You also have a #Bean annotated method which also leads to an instance. The latter is overridden with the first.
In short remove the #Component annotation as that isn't needed because you already have a factory method for this class.
public class ConfigurationSettings { ... }
You should also remove the #PropertySource annotations as Spring-Boot will already load the application.properties for you.
Finally you should not use the #ContextConfiguration annotation on your test class but the #SpringApplicationConfiguration and pass in your application class (not your configuration class!).
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes=OFAC.class)
public class OFAConfigurationTest {
#Autowired
private Environment environment;
#Autowired
private ConfigurationSettings configurationSettings;
#Test
public void testConfigurationLoads() {
assertNotNull(environment);
assertNotNull(configurationSettings);
}
#Test
public void testConfigurationSettingValues() {
assertEquals("Product Name", configurationSettings.getProduct());
assertEquals("0.0.1", configurationSettings.getVersion());
assertEquals("2014 Product", configurationSettings.getCopyright());
}
This will fix your runtime configuration problems and will let your test use the power of Spring Boot to configure your application.