Get JNDI resources programatically in spring - java

I have a Tomcat servlet container that has a list of DataSources managed by Tomcat's connection pool. From my Spring application (Spring 3.2.3) I would like to get one of these datasources on runtime, something like:
public class MyService {
#Autowired
private JndiObjectLocator jndiLocator;
public void myMethod(String jndiName) {
DataSource myDataSource = jndiLocator.locate(jndiName);
}
}
Any ideas on how to do that?

You can always do a JNDI lookup in your code, you can use the JndiDataSourceLookup for that and call the getDataSource() method.
public class MyService {
#Autowired
private JndiDataSourceLookup lookup;
public void myMethod(String jndiName) {
DataSource myDataSource = lookup.getDataSourcejndiName);
}
}
Another option would be to make your bean aware of the BeanFactory and retrieve the DataSource from there.
public class MyService {
#Autowired
private BeanFactory factory;
public void myMethod(String jndiName) {
DataSource myDataSource = factory.getBean(jndiName, DataSource.class);
}
}

Related

Autowired object is getting null

I am using Spring Boot for my application. I am defining JNDI name in the application.properties file.
When I am trying to get JdbcTemplate in below class, its null:
#Configuration
public class DemoClass
{
#Autowired
private JdbcTemplate template;
#Bean
private DataSource getDS(){
return template.getDataSource(); //NPE
}
}
Another Class
#Component
public class SecondClass {
#Autowired
private JdbcTemplate template;
public void show(){
template.getDataSource(): // Working Fine
}
}
I am not sure this configured by default.. In case it is not, then maybe you can try configuring it yourself:
#Autowired
DataSoure dataSource;
#Bean
public JdbcTemplate getJdbcTemplate() {
return new JdbcTemplate(dataSource);
}
in any case if you need only the DataSource, I think it is auto-configured by Spring Boot so you can autowire it directly when you need it.
#Repository
public class DataRepository {
private JdbcTemplate jdbcTemplate;
#Autowired
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
public int updateCandidate() {
return this.jdbcTemplate.update("update .... from table where ....");
}
}
application.properties
database connection details
spring.datasource.url=jdbc:oracle:thin:***
spring.datasource.username=Scott
spring.datasource.password=Tiger
spring.datasource.driver-class-name=oracle.jdbc.driver.OracleDriver
spring.datasource.tomcat.initial-size=1
spring.datasource.tomcat.max-active=1
spring.datasource.tomcat.min-idle=1
spring.datasource.tomcat.max-idle=1
If you're getting a NPE at getDS. This means JdbcTemplate hasn't been injected yet, maybe it couldn't be injected.
Give spring a hint at bean dependencies by
#Bean
public JdbcTemplate getJdbcTemplate(DataSource dataSource){
return new JdbcTemplate(dataSource)
}
Or
#Bean
#DependsOn("template")
public DataSouce getDS(){
return template.getDataSource();
}
By default #Autowired sets required=true so the DemoClass should not be constructed by Spring.
Most likely you are creating new DemoClass() or disabled the annotation config altogether and the DemoClass class is registered manually e.g. using XML.
Instead ensure that the DemoClass class is discovered using Spring's component scan e.g. using #SpringBootApplication or #ComponentScan e.g. as per this example.

Loading Properties from Database using Java Config with Spring Boot

I created a FactoryBean<Properties> as
public final class SystemProperteisFactoryBean implements FactoryBean<Properties> {
private static final String QUERY = "select * from tb_system_properties";
private final NamedParameterJdbcTemplate jdbcTemplate;
public SystemProperteisFactoryBean (DataSource datasource) {
this.jdbcTemplate = new NamedParameterJdbcTemplate (datasource);
}
#Override
public Properties getObject() {
Properties result = new Properties();
jdbcTemplate.query(QUERY,
(ResultSet rs) -> result.setProperty(rs.getString(1), rs.getString(2));
return result;
}
#Override
public Class<?> getObjectType() {
return Properties.class;
}
#Override
public boolean isSingletone() {
return true;
}
}
This class worked fine using Spring with XML config, I get DataSource using a JNDI name, and then created proper properties, and then used propertiesPlaceHoldeConfigurer via XML tag.
Now I want to use the same thing in Spring Boot and Java Config.
When I define a ProprtySourcesPlaceHolderConfigurer as a bean (in a static method in a #Configuration class) Spring tries to create this bean before the datasource.
Is there any way to create the datasource before PRopertySourcesPlaceHolderConfigurer?
Basically you need to take the dependency as a #Bean method parameter this way:
#Configuration
public static class AppConfig {
#Bean
public SystemPropertiesFactoryBean systemProperties(DataSource dataSource) {
return new SystemPropertiesFactoryBean(dataSource);
}
#Bean
public DataSource dataSource() {
// return new data source
}
}

Access Datasource inside Bean method injected at other Bean Method

In an spring boot project, is there a way to use injected object inside a #Bean method. In my example following, isdatasourceUse() method able to acccess injected Datasource (either from dev or war profile)
#EnableScheduling
#Configuration
#EnableAspectJAutoProxy
#Profile({ "dev", "war" })
public class AppConfig {
Logger logger = LoggerFactory.getLogger(AppConfig.class);
#Autowired
DBPropertyBean dbPropertyBean;
#Bean(destroyMethod = "")
#Profile("war")
public DataSource jndiDataSource() throws IllegalArgumentException, NamingException {
JndiObjectFactoryBean bean = new JndiObjectFactoryBean();
bean.setJndiName(dbPropertyBean.getJndiName());
bean.setProxyInterface(DataSource.class);
bean.setLookupOnStartup(false);
bean.afterPropertiesSet();
return (DataSource) bean.getObject();
}
#Bean(destroyMethod = "close")
#Profile("dev")
public DataSource getDataSource() throws Exception {
com.mchange.v2.c3p0.ComboPooledDataSource ds = new com.mchange.v2.c3p0.ComboPooledDataSource();
ds.setUser(dbPropertyBean.getDsUsername());
ds.setPassword(dbPropertyBean.getDsPassword());
ds.setJdbcUrl(dbPropertyBean.getDsJdbcUrl());
ds.setDriverClass(dbPropertyBean.getDsDriverClass());
ds.setMaxPoolSize(dbPropertyBean.getDsMaxPoolSize());
ds.setMinPoolSize(dbPropertyBean.getDsMinPoolSize());
ds.setInitialPoolSize(dbPropertyBean.getDsInitPoolSize());
ds.setAcquireIncrement(dbPropertyBean.getDsAcquireInc());
ds.setAcquireRetryAttempts(dbPropertyBean.getDsAcquireRetryAtt());
ds.setPreferredTestQuery(dbPropertyBean.getPreferredTestQuery());
ds.setIdleConnectionTestPeriod(dbPropertyBean.getIdleConnectionTestPeriod());
return ds;
}
#Bean
public void datasourceUse() {
//How to user datasource here
}
}
Use it like below:
#Autowired
public void datasourceUse(DataSource dataSource) {
System.out.println(dataSource);
}

Spring cloud default profile

On a project I'm currently working on, we have the need for multiple profiles, i.e. "default" and "cloud".
both DefaultContext and CloudContext contains the same bean definitions
We are using PCF(Pivotal Cloud Foundry)
we have created an interface
public interface Config {
public DataSource getDataSource();
public SomeService getService();
}
Then implement each profile with this interface
#Primary
#Configuration
#Profile("default")
public class DevConfig implements Config
{
public DataSource getDataSource() {
// create and return production datasource
}
public SomeService getService() {
// Create and return production service
}
}
And then do the same for cloud.
#Configuratio
#Profile("cloud")
public class CloudConfig extends AbstractCloudConfig implements Config
{
public DataSource getDataSource() {
// create and return dummy datasource
}
public SomeService getService() {
// Create and return dummy service
}
}
And we are Autowiring in the service call, in processor file.
#Service("processor")
public class Processor {
#Autowired Config dsConfig;
public object get(int Number)
{
return dao.get(Number,dsConfig.getDataSource());
}
}
If we deploy in PCF, its working fine, as the profile is cloud. If we are running in local, it should get the default profile, but dsConfig is null.
Could you please help on this.
#Configuration classes aren't availalbe for autowiring.
As #spencergibb pointed out in the comment you need to tell the container to make this classes available for autowiring.
For that annotate them with #Component.
Something like this:
#Component
#Profile("default")
public class DevConfig implements Config
{
public DataSource getDataSource() {
// create and return production datasource
}
public SomeService getService() {
// Create and return production service
}
}
In case it still doesn't work, check the following two points:
Do you have the configs (DevConfig and Cloudconfig) in different packages so the ContextScan doesn't find it?
Are you running in another profile locally? (like Dev).
You can put this snipped to your code (its from JHipster) to log the active profiles.
#Autowired
private Environment env;
/**
* Initializes Application.
* <p/>
* Spring profiles can be configured with a program arguments --spring.profiles.active=your-active-profile
* <p/>
*/
#PostConstruct
public void initApplication() throws IOException {
if (env.getActiveProfiles().length == 0) {
log.warn("No Spring profile configured, running with default configuration");
}
else {
log.info("Running with Spring profile(s) : {}", Arrays.toString(env.getActiveProfiles()));
}
}
I'd rather autowire datasource and service classes instead of configuration class.
In this way you wouldn't need any instance of configuration and directly autowire whatever class you want.
So the classes will look like below.
Default Config:
#Primary
#Configuration
#Profile("default")
public class DevConfig implements Config
{
#Bean
public DataSource getDataSource() {
// create and return production datasource
}
#Bean
public SomeService getService() {
// Create and return production service
}
}
Cloud Config:
#Configuration
#Profile("cloud")
public class CloudConfig extends AbstractCloudConfig implements Config
{
#Bean
public DataSource getDataSource() {
// create and return dummy datasource
}
#Bean
public SomeService getService() {
// Create and return dummy service
}
}
Processor Class:
#Service("processor")
public class Processor {
#Autowired
private DataSource dataSource;
public object get(int Number)
{
return dao.get(Number,datasource);
}
}

Autowired property is null - Spring Boot Configuration

I am stuck with null values in an autowired property. I am hoping I could get some help.
We are using for the project spring-boot version 0.5.0.M6.
The four configuration files with beans are in one package and are sorted by "area":
Data source configuration
Global method security configuration (as we use Spring-ACL)
MVC configuration
Spring Security configuration
The main method that bootstraps everything is in the following file:
#EnableAspectJAutoProxy
#EnableSpringConfigured
#EnableAutoConfiguration(exclude = {
DataSourceTransactionManagerAutoConfiguration.class,
HibernateJpaAutoConfiguration.class,
JpaRepositoriesAutoConfiguration.class,
SecurityAutoConfiguration.class,
ThymeleafAutoConfiguration.class,
ErrorMvcAutoConfiguration.class,
MessageSourceAutoConfiguration.class,
WebSocketAutoConfiguration.class
})
#Configuration
#ComponentScan
public class IntegrationsImcApplication {
public static void main(String[] args) throws Exception {
ApplicationContext ctx = SpringApplication.run(
IntegrationsImcApplication.c lass, args);
}
}
The first file that holds the data source configuration beans is as follows (I have omitted some method body parts to make it more readable):
#EnableTransactionManagement(mode = AdviceMode.ASPECTJ)
#Configuration
public class RootDataSourceConfig
extends TomcatDataSourceConfiguration
implements TransactionManagementConfigurer {
#Override
public DataSource dataSource() {
return jpaDataSource();
}
public PlatformTransactionManager annotationDrivenTransactionManager() {
return jpaTransactionManager();
}
#Bean
public HibernateExceptionTranslator hibernateExceptionTranslator() {
return new HibernateExceptionTranslator();
}
#Bean(name="jpaDataSource")
public DataSource jpaDataSource() {......}
#Bean(name = {"transactionManager","txMgr"})
public JpaTransactionManager jpaTransactionManager() {......}
#Bean(name = "entityManagerFactory")
public EntityManagerFactory jpaEmf() {......}
}
And here is the next configuration file, that depends on the data source from above. It has about 20 beans related to ACL configuration, but it fails on the firsts bean that uses data source:
#EnableGlobalMethodSecurity(prePostEnabled = true)
#Configuration
public class RootGlobalMethodSecurityConfig
extends GlobalMethodSecurityConfiguration
implements Ordered {
#Autowired
public DataSource dataSource;
#Override
public int getOrder() {
return IntegrationsImcApplication.ROOT_METHOD_SECURITY_CO NFIG_ORDER;
}
#Bean
public MutableAclService aclService()
throws CacheException, IOException {
MutableJdbcAclService aclService = new MutableJdbcAclService(
dataSource, aclLookupStrategy(), aclCache());
aclService.setClassIdentityQuery("SELECT ##IDENTITY");
aclService.setSidIdentityQuery("SELECT ##IDENTITY");
return aclService;
}
...................................
}
Basically invoking aclService() throws an error as dataSource is null. We have tried ordering the configuration files by implementing the Ordered interface. We also tried using #AutoConfigureAfter(RootDataSourceConfig.class) but this did not help either. Instead of doing #Autowired on the DataSource we also tried injecting the RootDataSourceConfig class itself, but it was still null. We tried using #DependsOn and #Ordered on those beans but again no success. It seems like nothing can be injected into this configuration.
The console output at the startup is listing the beans in the order we want them, with data source being the first. We are pretty much blocked by this.
Is there anything weird or unique we are doing here that is not working? If this is as designed, then how could we inject data source differently?
Repo: github
Eager initialization of a bean that depends on a DataSource is definitely the problem. The root cause is nothing to do with Spring Boot or autoconfiguration, but rather plain old-fashioned chicken and egg - method security is applied via an aspect which is wrapped around your business beans by a BeanPostProcessor. A bean can only be post processed by something that is initialized very early. In this case it is too early to have the DataSource injected (actually the #Configuration class that needs the DataSource is instantiated too early to be wrapped properly in the #Configuration processing machinery, so it cannot be autowired). My proposal (which only gets you to the same point with the missing AuthenticationManager) is to declare the GlobalMethodSecurityConfiguration as a nested class instead of the one that the DataSource is needed in:
#EnableGlobalMethodSecurity(prePostEnabled = true)
#Configuration
protected static class ActualMethodSecurityConfiguration extends GlobalMethodSecurityConfiguration {
#Autowired
#Qualifier("aclDaoAuthenticationProvider")
private AuthenticationProvider aclDaoAuthenticationProvider;
#Autowired
#Qualifier("aclAnonymousAuthenticationProvider")
private AnonymousAuthenticationProvider aclAnonymousAuthenticationProvider;
#Autowired
#Qualifier("aclExpressionHandler")
private MethodSecurityExpressionHandler aclExpressionHandler;
#Override
protected void configure(AuthenticationManagerBuilder auth)
throws Exception {
auth.authenticationProvider(aclDaoAuthenticationProvider);
auth.authenticationProvider(aclAnonymousAuthenticationProvider);
}
#Override
public MethodSecurityExpressionHandler createExpressionHandler() {
return aclExpressionHandler;
}
}
i.e. stick that inside the RootMethodSecurityConfiguration and remove the #EnableGlobalMethodSecurity annotation from that class.
I might have resolved the problem.
GlobalMethodSecurityConfiguration.class has the following setter that tries to autowire permission evaluators:
#Autowired(required = false)
public void setPermissionEvaluator(List<PermissionEvaluator> permissionEvaluators) {
....
}
And in my case the aclPermissionEvaluator() bean needs aclService() bean, which in turn depends on another autowired property: dataSource. Which seems not to be autowired yet.
To fix this I implemented BeanFactoryAware and get dataSource from beanFactory instead:
public class RootMethodSecurityConfiguration extends GlobalMethodSecurityConfiguration implements BeanFactoryAware {
private DataSource dataSource;
#Override
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
this.dataSource = beanFactory.getBean("dataSource", DataSource.class);
}
....
}
After this, other exception showed up, whereSecurityAutoConfiguration.class is complaining about missing AuthenticationManager, so I just excluded it from #EnableAutoConfiguration. I am not sure if its ideal, but I have custom security configuration, so this way everything works ok.

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