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Queries bean is null, how do I get it to populate?

so I'm trying to run a sql query within this java app. I think I have the DAO set up correctly but it can't find the XML file which contains my queries. The code in question for my DAO implementation is:
private Properties queries;
public void setQueries(Properties queries) {
this.queries = queries;
}
public Boolean checkAssigned(String Id) {
String sql = queries.getProperty("CHECK_IF_ASSIGNED");
Map<String,Object> params = new HashMap<>();
List<String> assignedList;
params.put(":Id",Id);
LOG.info("Checking to see if already assigned \n" + "sql=" + sql
+ "\n" + "params=" + params);
assignedList = getNamedParameterJdbcTemplate().query(sql,params,
new assignedMapper());
if (assignedList == null || assignedList.size() == 0) {
ScreenVo.setSwitch(false);
}
else {
ScreenVo.setSwitch(true);
}
return ScreenVo.getSwitch();
}
My DAO is just:
public interface ScreenDao {
Boolean checkAssigned(String Id);
}
My queries.xml file looks like:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util.xsd">
<util:properties id="queries">
<prop key="CHECK_IF_ASSIGNED">
<![CDATA[
--Long query
]]>
</prop>
</util:properties>
</beans>
The bean for the dao in the applicationContext.xml is:
<bean id="screenDaoImpl" class="com.corp.apps.actionator.dao.ScreenDaoImpl">
<property name="dataSource" ref="datasource"/>
<property name="queries" ref="queries"/>
</bean>
And my declaration of the queries file in the applicationContext is:
<import resource="classpath:queries.xml"/>
It's declared in my web.xml in a similar fashion.
I tried to include everything that could possibly be relevant. I've tried autowiring the bean in ScreenDaoImpl.java but that didn't work. I'm really not sure where to go from here, or what I might have done wrong.
EDIT:
The exception I'm getting is:
javax.faces.event.MethodExpressionActionListener.processAction java.lang.NullPointerException
And my screenDaoImpl is declared before use as:
private static ScreenDao screenDao = new ScreenDaoImpl();

Spring-Bean screenDaoImpl must be created through Spring context, in this case Spring can inject required properties (dataSource and queries) in created bean.
I don't know your architecture of application. But I can offer you a couple of ways.
1 - If you want use screenDaoImpl in spring-bean which declared in spring-xml then you can do it like this:
<bean id="screenServiceImpl" class="com.corp.apps.actionator.service.ScreenServiceImpl">
<property name="screenDao" ref="screenDaoImpl"/>
</bean>
The better way is make all your application in Spring. And create (and inject) beans by spring-context xml. Do not create bean-objects by new. Spring can not inject properties in these objects.
If it is difficult then try to find examples of applications on the Spring site. Maybe try spring-boot (without xml).
2 - If you want use screenDaoImpl in non-spring object you can get screenDaoImpl from spring-context by "bridge". Create class:
package com.corp.apps.actionator.util;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
public class AppSpringBridge implements ApplicationContextAware {
private static ApplicationContext context;
public void setApplicationContext(ApplicationContext context) throws BeansException {
this.context = context;
}
public static ApplicationContext getApplicationContext() {
return context;
}
}
Define bean in application-context.xml:
<bean id="springBridge" class="com.corp.apps.actionator.util.AppSpringBridge />
Spring create this bean, but method getApplicationContext() (and context property) of this bean is static. And we can use getApplicationContext() in any methods:
ScreenDao screenDao = (ScreenDao)AppSpringBridge.getApplicationContext().getBean("screenDaoImpl");

I fixed it, and for posterity's sake I'll post my solution here:
First I autowired my screenDao bean in the invoking class, and then I created a static method to set screenDao.
#Autowired
private static ScreenDao screenDao;
#PostConstruct
public static void setScreenDao(ScreenDao newScreenDao) {
screenDao = newScreenDao;
}
#PostConstruct
public ScreenDao getScreenDao() {
return screenDao;
}
I'm not really sure if getScreenDao does anything but I added it as well.
Then in my application context I created a bean I called initialize to invoke the static method.
<bean id="initialize" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
<property name="targetClass" value="com.corp.apps.consolidator.backing.ScreenBean"/>
<property name="targetMethod" value="setScreenDao"/>
<property name="arguments">
<list>
<ref bean="screenDao"/>
</list>
</property>
</bean>
These two changes resolved my issue.

No qualifying bean of type available

Exception in thread "main" org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.spring.dto.Car2' available
Controller.java -
public class Controller {
public static void main(String[] args) {
ConfigurableApplicationContext context = new ClassPathXmlApplicationContext("configu.xml");
Car2 c2 = (Car2) context.getBean(Car2.class);
System.out.println(c2);
}
}
Car2.java -
#ToString #Component
public class Car2 {
#Autowired
private Engine engine;
}
Engine.java -
#Setter #ToString
public class Engine {
private String modelYear;
}
configu.xml -
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<context:component-scan base-package="com.spring.dto.Car2" />
<context:annotation-config />
<bean class="com.spring.dto.Engine">
<property name="modelYear" value="2015"></property>
</bean>
</beans>
please ignore the annotation #ToString and #Setter- I am using Lombok project for my simplicity.

I think the error is here:
<context:component-scan base-package="com.spring.dto.Car2" />
The value should be a package, not a class. Change it to "com.spring.dto", then it should work.

spring framework null pointer exception

Trying to autowire Spring bean with property, but still getting NPE. Snippets:
INFO: Loading XML bean definitions from class path resource [autoWireByName.xml]
Exception in thread "main" today do push-ups for 30 mins
java.lang.NullPointerException
at com.springAutoWireByName.KabadiCoach.getFortune(KabadiCoach.java:23)
at com.springAutoWireByName.AutoWireByName.main(AutoWireByName.java:13)
KabadiCoach.java
package com.springAutoWireByName;
public class KabadiCoach {
private SadFortune sadFortune;
/*public KabadiCoach(){
System.out.println("inside default Constructor");
}*/
public String getDailyWorkout()
{
return "today do push-ups for 30 mins";
}
public void setSadFortune(SadFortune fortune) {
sadFortune = fortune;
}
public String getFortune() {
return sadFortune.getSadFortune();
}
}
SadFortune.java
package com.springAutoWireByName;
public class SadFortune {
public String getSadFortune()
{
System.out.println();
return "your day wont be good enough Sorry!!!";
}
}
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- bean definitions here -->
<bean name="Fortune" class="com.springAutoWireByName.SadFortune">
</bean>
<bean id="myCoach" class="com.springAutoWireByName.KabadiCoach" autowire="byName" />
<!-- this is just a prototype to define actual just make use of this file-->
</beans>
main
package com.springAutoWireByName;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class AutoWireByName {
public static void main(String[] args) {
ClassPathXmlApplicationContext context =new ClassPathXmlApplicationContext("autoWireByName.xml");
KabadiCoach co = context.getBean("myCoach",KabadiCoach.class);
System.out.println(co.getDailyWorkout());
System.out.println(co.getFortune());
}
}
after running the above code I am getting the error message as listed and when I change the method to static
public static String getSadFortune()
{
System.out.println();
return "your day wont be good enough Sorry!!!";
}
In class 2 I got the desired output. Why?

Basically the SadFortune member is still null, which is why it works if the getSadFortune() method will be made static.
Until now you only tell Spring to instantiate a Fortune bean and a KabadiCoach, but you have to tell Spring that some members in the KabadiCoach need to be autowired too.
Try this in your Spring configuration file:
<bean id="fortune" class="com.springAutoWireByName.SadFortune"></bean>
<bean id="myCoach" class="com.springAutoWireByName.KabadiCoach" autowire="byName">
<property name="fortune" ref="fortune" />
</bean>
EDIT: Sorry, overread the autowire="byName" attribute. In this case you probably just have write the name in lower case.
<bean id="fortune" class="com.springAutoWireByName.SadFortune"/>
<bean id="myCoach" class="com.springAutoWireByName.KabadiCoach" autowire="byName"/>

Null pointer exception while using simple example of jdbcTemplate in Spring

I am learning JdbcTemplate with Spring and when i am running my java application i am getting null pointer on this line:
return jdbcTemplate.queryForMap(sql, id);
Please find the whole class below:
public class CustomerDaoImpl implements CustomerDAO{
private DataSource dataSource;
private JdbcTemplate jdbcTemplate;
public void setDataSource(DataSource ds) {
dataSource = ds;
}
public Map getCustomerById(String id) {
String sql = "SELECT * FROM CUSTOMER WHERE CUST_ID = ?";
return jdbcTemplate.queryForMap(sql, id);
}
Please find my SpringContext file below:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
<!-- Scans within the base package of the application for #Components to
configure as beans -->
<context:property-placeholder location="classpath:db.properties" />
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${db.driver}" />
<property name="url" value="${db.url}" />
<property name="username" value="${db.username}" />
<property name="password" value="${db.password}" />
</bean>
<bean id="customerDAO" class="com.tuto.dao.impl.CustomerDaoImpl">
<property name="dataSource" ref="dataSource" />
</bean>
</beans>
Please find my Main method below:
public class JdbcTemplateApp {
public static void main(String[] args) {
// if you have time,
// it's better to create an unit test rather than testing like this :)
ApplicationContext context = new ClassPathXmlApplicationContext(
"integration.xml");
CustomerDAO customerDAO = (CustomerDAO) context.getBean("customerDAO");
Map customerA = customerDAO.getCustomerById("1");
System.out.println("Customer A : " + customerA);
}
}
Please find below my exception in eclipse console:
INFO: Loaded JDBC driver: oracle.jdbc.driver.OracleDriver
Exception in thread "main" java.lang.NullPointerException
at com.tuto.dao.impl.CustomerDaoImpl.getCustomerById(CustomerDaoImpl.java:23)
at com.tuto.main.JdbcTemplateApp.main(JdbcTemplateApp.java:23)
Any idea why it is null please?
Thanks in advance for any help

Change setDataSource to:
public void setDataSource(DataSource ds) {
jdbcTemplate = new JdbcTemplate(ds);
}

You can extend org.springframework.jdbc.core.support.JdbcDaoSupport in your DAOImpl Class and use inherited getJdbcTemplate() method to get the jdbcTemplate. in this case you can remove the variable jdbcTemplate from your class

You never initialize jdbcTemlpate instance variable. In this case it's initialized as null and you're getting NullPointerException (you can't call methods on null). You need to initialize jdbcTemplate by yourself.
To quote Java Language Specification:
Each class variable, instance variable, or array component is
initialized with a default value when it is created [...] For all
reference types the default value is null.

BeanCreationException : Injection of autowired dependencies failed

I have 2 classes in 2 different projects, and I have some difficulties to autowire a field.
In project pack, I have this Computation class :
package fr.aaa;
#Component
public class Computation {
#Autowired
#Qualifier("curveDAO")
CurveAccess curveDAO;
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("classpath*:applicationContext.xml");
}
}
In project db, I have this CurveAccess interface :
package com.bbb
public interface CurveAccess {
// some methods
}
implemented by a CurveDAO class :
package com.bbb.impl
#Repository("curveDAO")
#Transactional("cvaTxManager")
public class CurveDAO implements CurveAccess {
// some methods
}
My applicationContext.xml file from pack project :
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:tx="http://www.springframework.org/schema/tx" xmlns:util="http://www.springframework.org/schema/util"
xmlns:security="http://www.springframework.org/schema/security" xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.1.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd
http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-3.0.3.xsd">
<import resource="classpath:spring/persistence.xml"/>
<context:annotation-config />
<context:component-scan base-package="fr.aaa.*, com.bbb.*"/>
<util:properties id="jdbcProps" location="jdbc.properties" />
<bean id="propertyConfigurer"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<list>
<value>classpath:configuration.properties</value>
<value>classpath:jdbc.properties</value>
</list>
</property>
</bean>
When running, I have this exception :
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'Computation': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.bbb.CurveAccess fr.aaa.Computation.curveDAO; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.bbb.CurveAccess] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {#org.springframework.beans.factory.annotation.Autowired(required=true), #org.springframework.beans.factory.annotation.Qualifier(value=curveDAO)}
How can I solve this problem ?

Actually, your code works perfectly fine:
#SpringBootApplication
public class So21481801Application implements CommandLineRunner {
public interface CurveAccess {
String hello();
}
#Repository("curveDAO")
public class CurveDAO implements CurveAccess {
#Override
public String hello() {
return "Hello";
}
}
#Repository("curveDAOWorld")
public class CurveDAOWorld implements CurveAccess {
#Override
public String hello() {
return "World";
}
}
#Autowired
#Qualifier("curveDAO")
CurveAccess curveDAO;
#Autowired
#Qualifier("curveDAOWorld")
CurveAccess curveDAOWorld;
#Override
public void run(String... args) {
System.out.println(curveDAO.hello());
System.out.println(curveDAOWorld.hello());
}
public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(So21481801Application.class, args);
context.close();
}
}
Probably you have some problem on how you are using the component-scan configuration on XML and the Java annotations. Mix them is not a good idea.

You need a class that implements CurveAccess interface
#Component
public class CurveAccessImpl implements CurveAccess {
//methods
}
Also remove Qualifier from curveDao in Computation bean since there is no such bean with id curveDao.
#Autowired
CurveAccess curveDAO;