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POdataSource.getConnection throwing NullpointerException in Spring
 

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    <p>I am trying to connect to MySQL database in my spring application. I am able to connect to it if I use <code>DriverManager.getConnection(DB_URL,USER, PASS)</code> but unable to get connection with dataSource which is configured with bean.</p> <p>App context</p> <pre><code>&lt;bean id="jdbcTest" class="org.springdemo.jdbc.JdbcTest"&gt; &lt;property name="dataSource" ref="dataSource"&gt;&lt;/property&gt; &lt;/bean&gt; &lt;bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"&gt; &lt;property name="driverClassName" value="com.mysql.jdbc.Driver"&gt;&lt;/property&gt; &lt;property name="url" value="jdbc:mysql://localhost:3306/test"&gt;&lt;/property&gt; &lt;property name="username" value="xxxx"&gt;&lt;/property&gt; &lt;property name="password" value="xxxx"&gt;&lt;/property&gt; &lt;/bean&gt; </code></pre> <p>Class</p> <pre><code>public class JdbcTest { private DataSource dataSource; public JdbcTest(){ try { Class.forName("com.mysql.jdbc.Driver"); //conn = DriverManager.getConnection(DB_URL,USER,PASS); This worked!!!! conn = dataSource.getConnection(); stmt = conn.createStatement(); } catch (SQLException e) { e.printStackTrace(); } } public ResultSet executeQuery(String query){ //executing query; it works as I tested with DriverManager } public static void main(String[] args) { AbstractApplicationContext context = new ClassPathXmlApplicationContext("spring.xml"); JdbcTest test = context.getBean("jdbcTest", JdbcTest.class); ResultSet rs = test.executeQuery("select * from employee"); try { while(rs.next()){ System.out.println(rs.getString(1)); } } catch (SQLException e) { e.printStackTrace(); } } } </code></pre> <p>It worked perfectly fine when I use <code>DriverManager</code> but, when I use <code>DataSource</code> object to get connection which is configured with bean, it gives <code>NullPointerException</code></p> <pre><code> Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jdbcTest' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springdemo.jdbc.JdbcTest]: Constructor threw exception; nested exception is java.lang.NullPointerException at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1011) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:957) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:490) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:461) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:293) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:290) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:192) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:607) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479) at org.springframework.context.support.ClassPathXmlApplicationContext.&lt;init&gt;(ClassPathXmlApplicationContext.java:139) at org.springframework.context.support.ClassPathXmlApplicationContext.&lt;init&gt;(ClassPathXmlApplicationContext.java:83) at org.springdemo.DrawingApp.main(DrawingApp.java:21) Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springdemo.jdbc.JdbcTest]: Constructor threw exception; nested exception is java.lang.NullPointerException at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:162) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:87) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1004) ... 13 more Caused by: java.lang.NullPointerException at org.springdemo.jdbc.JdbcTest.&lt;init&gt;(JdbcTest.java:47) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:147) ... 15 more </code></pre>
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