spring mvc jadbc webapp 中的自动装配 bean 失败
autowiring bean failed in spring mvc jadbc webapp
我正在学习使用 spring。我正在使用 spring 和 jdbc 开发应用程序。 运行.
时出现以下异常
Nov 03, 2015 2:42:22 PM org.apache.catalina.core.ApplicationContext log
SEVERE: StandardWrapper.Throwable
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.dao.StudentDaoImp com.controller.StudentController.studentDaoImp; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentDaoImp' defined in file [C:\Users\Mrunal\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\SpringMVC\WEB-INF\classes\com\dao\StudentDaoImp.class]: Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5253)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5543)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardContext.reload(StandardContext.java:4020)
at org.apache.catalina.loader.WebappLoader.backgroundProcess(WebappLoader.java:425)
at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1344)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1545)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1555)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1555)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1523)
at java.lang.Thread.run(Unknown Source)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.dao.StudentDaoImp com.controller.StudentController.studentDaoImp; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentDaoImp' defined in file [C:\Users\Mrunal\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\SpringMVC\WEB-INF\classes\com\dao\StudentDaoImp.class]: Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
... 31 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentDaoImp' defined in file [C:\Users\Mrunal\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\SpringMVC\WEB-INF\classes\com\dao\StudentDaoImp.class]: Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:275)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1139)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1042)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
... 33 more
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163)
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:122)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:267)
... 45 more
Caused by: java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.jdbc.support.JdbcAccessor.afterPropertiesSet(JdbcAccessor.java:135)
at org.springframework.jdbc.core.JdbcTemplate.<init>(JdbcTemplate.java:169)
at com.dao.StudentDaoImp.<init>(StudentDaoImp.java:18)
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)
... 47 more
我的调度程序 servlet 看起来像
<!-- declaring base package -->
<context:component-scan base-package="com" />
<bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
</bean>
<!-- declare datasource bean -->
<bean id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
<property name="url"
value="jdbc:sqlserver://localhost:49155;databaseName=Test;instancename=mssqlserver1;" />
<property name="username" value="sa" />
<property name="password" value="abc123" />
</bean>
<bean id="StudentDao" class="com.dao.StudentDaoImp" >
<constructor-arg ref="dataSource" />
</bean>
and my controller class looks like
public class StudentDaoImp {
@Autowired
DataSource dataSource;
JdbcTemplate jdbcTemplateObject = new JdbcTemplate(dataSource);
@Autowired
public StudentDaoImp(DataSource dataSource)
{
this.dataSource = dataSource;
}
public void create(String name, Integer age) {
String SQL = "insert into Student (name, age) values (?, ?)";
jdbcTemplateObject.update( SQL, name, age);
System.out.println("Created Record Name = " + name + " Age = " + age);
return;
}
public Student getStudent(Integer id) {
String SQL = "select * from Student where id = ?";
Student student = jdbcTemplateObject.queryForObject(SQL,
new Object[]{id}, new StudentMapper());
return student;
}
}
我尝试了很多选项，但我找不到错误。有人知道答案吗？
问题已解决。
由于这条语句而产生了问题
JdbcTemplate jdbcTemplateObject = new JdbcTemplate(dataSource);
实例变量在构造函数之前初始化，因此它将 null 变量带入数据源。
我关注了
JdbcTemplate jdbcTemplateObject;
@Autowired
public StudentDaoImp(DataSource dataSource)
{
this.dataSource = dataSource;
jdbcTemplateObject = new JdbcTemplate(this.dataSource);
}
我正在学习使用 spring。我正在使用 spring 和 jdbc 开发应用程序。 运行.
时出现以下异常Nov 03, 2015 2:42:22 PM org.apache.catalina.core.ApplicationContext log
SEVERE: StandardWrapper.Throwable
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.dao.StudentDaoImp com.controller.StudentController.studentDaoImp; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentDaoImp' defined in file [C:\Users\Mrunal\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\SpringMVC\WEB-INF\classes\com\dao\StudentDaoImp.class]: Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5253)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5543)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardContext.reload(StandardContext.java:4020)
at org.apache.catalina.loader.WebappLoader.backgroundProcess(WebappLoader.java:425)
at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1344)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1545)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1555)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1555)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1523)
at java.lang.Thread.run(Unknown Source)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.dao.StudentDaoImp com.controller.StudentController.studentDaoImp; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentDaoImp' defined in file [C:\Users\Mrunal\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\SpringMVC\WEB-INF\classes\com\dao\StudentDaoImp.class]: Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
... 31 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentDaoImp' defined in file [C:\Users\Mrunal\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\SpringMVC\WEB-INF\classes\com\dao\StudentDaoImp.class]: Bean instantiation via constructor failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:275)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1139)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1042)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
... 33 more
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.dao.StudentDaoImp]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163)
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:122)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:267)
... 45 more
Caused by: java.lang.IllegalArgumentException: Property 'dataSource' is required
at org.springframework.jdbc.support.JdbcAccessor.afterPropertiesSet(JdbcAccessor.java:135)
at org.springframework.jdbc.core.JdbcTemplate.<init>(JdbcTemplate.java:169)
at com.dao.StudentDaoImp.<init>(StudentDaoImp.java:18)
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)
... 47 more
我的调度程序 servlet 看起来像
<!-- declaring base package -->
<context:component-scan base-package="com" />
<bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
</bean>
<!-- declare datasource bean -->
<bean id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
<property name="url"
value="jdbc:sqlserver://localhost:49155;databaseName=Test;instancename=mssqlserver1;" />
<property name="username" value="sa" />
<property name="password" value="abc123" />
</bean>
<bean id="StudentDao" class="com.dao.StudentDaoImp" >
<constructor-arg ref="dataSource" />
</bean>
and my controller class looks like
public class StudentDaoImp {
@Autowired
DataSource dataSource;
JdbcTemplate jdbcTemplateObject = new JdbcTemplate(dataSource);
@Autowired
public StudentDaoImp(DataSource dataSource)
{
this.dataSource = dataSource;
}
public void create(String name, Integer age) {
String SQL = "insert into Student (name, age) values (?, ?)";
jdbcTemplateObject.update( SQL, name, age);
System.out.println("Created Record Name = " + name + " Age = " + age);
return;
}
public Student getStudent(Integer id) {
String SQL = "select * from Student where id = ?";
Student student = jdbcTemplateObject.queryForObject(SQL,
new Object[]{id}, new StudentMapper());
return student;
}
}
我尝试了很多选项，但我找不到错误。有人知道答案吗？
问题已解决。
由于这条语句而产生了问题 JdbcTemplate jdbcTemplateObject = new JdbcTemplate(dataSource);
实例变量在构造函数之前初始化，因此它将 null 变量带入数据源。
我关注了
JdbcTemplate jdbcTemplateObject;
@Autowired
public StudentDaoImp(DataSource dataSource)
{
this.dataSource = dataSource;
jdbcTemplateObject = new JdbcTemplate(this.dataSource);
}