Spring整合jdbcTemplate模板报错

Caused by: org.springframework.beans.NotWritablePropertyException: Invalid property 'jt' of bean class [cn.itcast.a_jdbctemplate.UserDaoImpl]: Bean property 'jt' is not writable or has an invalid setter method. Does the parameter type of the setter match the return type of the getter?

在家自学Spring，遇到Spring整合jdbc的异常问题:

UserDao.java

package cn.itcast.a_jdbctemplate;

import java.util.List;

import cn.itcast.bean.User;

public interface UserDao {
      void save(User u);
      void delete(Integer id);
      void update(User u);
      User getById(Integer id);
      int getTotalCount();
      List<User> getAll();
}

UserDaoImpl.java如下:

package cn.itcast.a_jdbctemplate;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;

import cn.itcast.bean.User;

public class UserDaoImpl  implements UserDao{

 private JdbcTemplate jt;

 @Override
 public void save(User u) {
  String sql ="insert into t_user values(null,?)";
  jt.update(sql,u.getName());
 }

 @Override
 public void delete(Integer id) {
  String sql="delete from t_user where id=?";
  jt.update(sql,id);
  
 }

 @Override
 public void update(User u) {
  String sql = "update t_user set name=? where id=?";
  jt.update(sql,u.getName(),u.getId());
 }

 @Override
 public User getById(Integer id) {
  String sql = "select * from t_user where id = ? ";
  return jt.queryForObject(sql,new RowMapper<User>(){
   @Override
   public User mapRow(ResultSet rs, int arg1) throws SQLException {
    User u = new User();
    u.setId(rs.getInt("id"));
    u.setName(rs.getString("name"));
    return u;
   }}, id);
 }

 @Override
 public int getTotalCount() {
  String sql = "select count(*) from t_user ";
  Integer count = jt.queryForObject(sql, Integer.class);
  return count;
 }

 @Override
 public List<User> getAll() {
  String sql = "select * from t_user";
  List<User> list = jt.query(sql, new RowMapper<User>(){
   @Override
   public User mapRow(ResultSet rs, int arg1) throws SQLException {
    User u = new User();
    u.setId(rs.getInt("id"));
    u.setName(rs.getString("name"));
    return u;
   }});
  return list;
 }
 

}

User.java如下:

package cn.itcast.bean;

public class User {
      private Integer id;
      private String name;
 public Integer getId() {
  return id;
 }
 public void setId(Integer id) {
  this.id = id;
 }
 public String getName() {
  return name;
 }
 public void setName(String name) {
  this.name = name;
 }
     
}

applicationContext.xml配置如下：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd ">
<!-- 将连接池放入spring容器 -->
<bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
    <property name="jdbcUrl" value ="jdbc:mysql:///hibernate_32"></property>
    <property name="driverClass" value ="com.mysql.jdbc.Driver"></property>
    <property name="user" value ="root"></property>
    <property name="password" value ="jack1220"></property>
</bean>
<!-- 将JDBCTemplate放入spring容器 -->
<bean name="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
     <property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 将UserDao放入spring容器 -->
<bean name="userDao" class="cn.itcast.a_jdbctemplate.UserDaoImpl">
     <property name="jt" ref="jdbcTemplate"></property>
</bean>
</beans>

测试类demo.java如下:

package cn.itcast.a_jdbctemplate;

import java.beans.PropertyVetoException;

import javax.annotation.Resource;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.mchange.v2.c3p0.ComboPooledDataSource;

import cn.itcast.bean.User;

//演示JDBC模板
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class Demo {
 @Resource(name="userDao")
 private UserDao ud;
  
 @Test
 public void fun1() throws Exception{
  ComboPooledDataSource dataSource = new ComboPooledDataSource();
  dataSource.setDriverClass("com.mysql.jdbc.Driver");
  dataSource.setJdbcUrl("jdbc:mysql:///hibernate_32");
  dataSource.setUser("root");
  dataSource.setPassword("jack1220");
  JdbcTemplate jt = new JdbcTemplate();
  
  jt.setDataSource(dataSource);
  
  //2.书写sql,并执行
  String sql ="insert into t_user values(null,'James')";
  jt.update(sql);
 }
 
 @Test
 public void fun2() throws Exception{
  User u = new User();
  u.setName("tommy");
  ud.save(u);
 }
 
 @Test
 public void fun4() throws Exception{
  ud.delete(2);
 }
 
 @Test
 public void fun5() throws Exception{
     System.out.println(ud.getTotalCount());
 }
  
}package cn.itcast.a_jdbctemplate;

import java.beans.PropertyVetoException;

import javax.annotation.Resource;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.mchange.v2.c3p0.ComboPooledDataSource;

import cn.itcast.bean.User;

//演示JDBC模板
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class Demo {
@Resource(name="userDao")
private UserDao ud;

@Test
public void fun1() throws Exception{
ComboPooledDataSource dataSource = new ComboPooledDataSource();
dataSource.setDriverClass("com.mysql.jdbc.Driver");
dataSource.setJdbcUrl("jdbc:mysql:///hibernate_32");
dataSource.setUser("root");
dataSource.setPassword("jack1220");
JdbcTemplate jt = new JdbcTemplate();

jt.setDataSource(dataSource);

//2.书写sql,并执行
String sql ="insert into t_user values(null,'James')";
jt.update(sql);
}

@Test
public void fun2() throws Exception{
User u = new User();
u.setName("tommy");
ud.save(u);
}

@Test
public void fun4() throws Exception{
ud.delete(2);
}

@Test
public void fun5() throws Exception{
System.out.println(ud.getTotalCount());
}

}

报错:

Caused by: org.springframework.beans.NotWritablePropertyException: Invalid property 'jt' of bean class [cn.itcast.a_jdbctemplate.UserDaoImpl]: Bean property 'jt' is not writable or has an invalid setter method. Does the parameter type of the setter match the return type of the getter?

改进方法:在UserDaoImpl中加入jdbcTemplate jt的set方法，测试就成功过了