整合ssh使用hibernateTemplate的find方法报空指针？

这是entity类

package com.tjw.mysql.model;
import javax.annotation.Generated;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

import org.springframework.stereotype.Component;

@Component("admin")
@Entity
public class Admin {
	private int id ;
	private String name ;
	private String password ;
	private int grade ;


	@Id

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public int getGrade() {
		return grade;
	}
	public void setGrade(int grade) {
		this.grade = grade;
	}
}

这是实现类

package com.tjw.mysql.dao.impl;

import java.io.Serializable;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import javax.annotation.Resource;
import javax.jms.Session;

import org.hibernate.Query;
import org.springframework.orm.hibernate3.HibernateTemplate;
import org.springframework.stereotype.Component;


import com.tjw.mysql.dao.AdminDAO;
import com.tjw.mysql.model.Admin;



@Component("adminDAO")
public class AdminImpl implements AdminDAO{
	private HibernateTemplate hibernateTemplate; 
	public void doCreate(Admin admin)  {
		// TODO Auto-generated method stub
		hibernateTemplate.save(admin);
	}

	public boolean doCreateOrdoUpdate(Admin admin) {
		// TODO Auto-generated method stub
		return false;
	}

	public void doDelete(Admin admin)  {

		this.hibernateTemplate.delete(admin);

	}

	public void doUpdate(Admin admin) {
		// TODO Auto-generated method stub
		this.hibernateTemplate.update(admin);
	}

	public List<Admin> findAll(){
		// TODO Auto-generated method stub
		 

		List<Admin> list = (List<Admin>)this. hibernateTemplate.find("from Admin");
		return list ; 
	}

	public Admin findById(int id) {
		// TODO Auto-generated method stub
		return null;
	}

	public int getCount() {
		// TODO Auto-generated method stub
		return 0;
	}

	public HibernateTemplate getHibernateTemplate() {
		return hibernateTemplate;
	}
	@Resource
	public void setHibernateTemplate(HibernateTemplate hibernateTemplate) {
		this.hibernateTemplate = hibernateTemplate;
	}

}

这是配置文件

<?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"
	xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
           http://www.springframework.org/schema/context
           http://www.springframework.org/schema/context/spring-context-2.5.xsd
           http://www.springframework.org/schema/aop
           http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
           http://www.springframework.org/schema/tx 
           http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">
	<context:annotation-config />
	<context:component-scan base-package="com.tjw.mysql.model" />
	<context:component-scan base-package="com.tjw.mysql.service" />
	<context:component-scan base-package="com.tjw.mysql.dao.impl" />

	<!-- 
		<bean id="dataSource"
		class="org.apache.commons.dbcp.BasicDataSource"
		destroy-method="close">


		<property name="driverClassName" value="com.mysql.jdbc.Driver" />
		<property name="url" value="jdbc:mysql://localhost:3306/spring" />
		<property name="username" value="root" />
		<property name="password" value="bjsxt" />
		</bean>
	-->

	<bean
		class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="locations">
			<value>classpath:jdbc.properties</value>
		</property>
	</bean>

	<bean id="dataSource" destroy-method="close"
		class="org.apache.commons.dbcp.BasicDataSource">
		<property name="driverClassName"
			value="${jdbc.driverClassName}" />
		<property name="url" value="${jdbc.url}" />
		<property name="username" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}" />
	</bean>

	<bean id="sessionFactory"
		class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
		<property name="dataSource" ref="dataSource" />
		<!-- 
		<property name="annotatedClasses">
			<list>
				<value>com.bjsxt.model.User</value>
				<value>com.bjsxt.model.Log</value>
			</list>
		</property>
		下面是为了表明哪些是被entity注解标识的
		 -->
		 <property name="packagesToScan">
			<list>
				<value>com.tjw.mysql.model</value>

			</list>
		</property>
		<property name="hibernateProperties">
			<props>
				<prop key="hibernate.dialect">
					org.hibernate.dialect.MySQLDialect
				</prop>
				<prop key="hibernate.show_sql">true</prop>
			</props>

		</property>
	</bean>

	<bean id="txManager"
		class="org.springframework.orm.hibernate3.HibernateTransactionManager">
		<property name="sessionFactory" ref="sessionFactory" />
	</bean>

	<aop:config>
		<aop:pointcut id="bussinessService"
			expression="execution(public * com.bjsxt.service..*.*(..))" />
		<aop:advisor pointcut-ref="bussinessService"
			advice-ref="txAdvice" />
	</aop:config>

	<tx:advice id="txAdvice" transaction-manager="txManager">
		<tx:attributes>
			<tx:method name="getUser" read-only="true" />
			<tx:method name="add*" propagation="REQUIRED"/>
		</tx:attributes>
	</tx:advice>

	<bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate">
		<property name="sessionFactory" ref="sessionFactory"></property>
	</bean>

</beans>

简单地这样调用
AdminImpl adminImpl = new AdminImpl();
adminImpl.findAll();
报出异常
java.lang.NullPointerException
at com.tjw.mysql.dao.impl.AdminImpl.findAll(AdminImpl.java:52)
at com.tjw.mysql.model.TestAdmin.testStudent(TestAdmin.java:101)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:38)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)

这是为什么呢？我在beans.xml配置文件里不是把sessionFactory和hibernateTemplate都注入了吗怎么还出现空指针的异常呢

5 个解决方案

#1

解决问题了，使用getBean的方式就可以得到find()的list,但这是为什么呢

#2

都没有获取bean，就不会执行，就不能得到了

#3

额，原来是这样，感谢

#4

我也遇到了您文章中的问题，能说下您是怎么解决的吗？main中是怎么处理的

#5

能说说是怎么解决的吗，我都高了好长时间了