Spring案例无法运行不报错
项目结构（配置文件只用到第三个student那个）
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.itheima</groupId>
<artifactId>chapter09</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>5.2.8.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>5.2.8.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>5.2.8.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.2.8.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-expression</artifactId>
<version>5.2.8.RELEASE</version>
</dependency>
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.2</version>
</dependency>
<!-- jdbc包 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>5.2.10.RELEASE</version>
</dependency>
<!-- spring-tx包 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>5.2.10.RELEASE</version>
</dependency>
<!-- MySQL数据库驱动 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.11</version>
<scope>runtime</scope>
</dependency>
<!-- aspectjweaver依赖 -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.9.6</version>
<scope>runtime</scope>
</dependency>
<!-- aopalliance依赖包 -->
<dependency>
<groupId>aopalliance</groupId>
<artifactId>aopalliance</artifactId>
<version>1.0</version>
</dependency>
</dependencies>
</project>
测试类StudentController
package demo666;
import demo666.StudentDao;
import demo666.Student;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import java.util.List;
import java.util.Scanner;
public class StudentController {
public static void main(String[] args) {
System.out.println("欢迎来到学生管理系统");
System.out.println("请输入用户名：");
Scanner sca = new Scanner(System.in);
String name = sca.nextLine();
// 加载配置文件
ApplicationContext applicationContext = new
ClassPathXmlApplicationContext("applicationContext-student.xml");
// 获取AccountDao实例
StudentDao studentDao = (StudentDao) applicationContext.getBean("studentDao");
// 执行findAllAccount()方法,获取Account对象的集合
List<Student> student = studentDao.findAllStudent();
// 循环输出集合中的对象
for (Student stu : student) {
if (name.equals(stu.getUsername())) {
System.out.println("请输入" + stu.getUsername() + "的密码：");
String mima = sca.nextLine();
if (mima.equals(stu.getPassword())) {
System.out.println("用户登录成功！");
System.out.println(stu.getUsername() + "是" + stu.getCourse() + "班的");
return;
}
} else {
System.out.println("账号密码错误！");
return;
}
}
}
}
配置文件applicationContext-student（数据库8.0）
<?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:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.3.xsd">
<!-- 1.配置数据源 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<!--数据库驱动 -->
<property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
<!--连接数据库的url -->
<property name="url" value="jdbc:mysql://localhost/spring?useSSL=false"/>
<!--连接数据库的用户名 -->
<property name="username" value="root"/>
<!--连接数据库的密码 -->
<property name="password" value="root"/>
</bean>
<!-- 2.配置JDBC模板 -->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<!-- 默认必须使用数据源 -->
<property name="dataSource" ref="dataSource"/>
</bean>
<!-- 3.定义id为studentDao的Bean -->
<bean id="studentDao" class="demo666.StudentDaoImpl">
<!-- 将jdbcTemplate注入到AccountDao实例中 -->
<property name="jdbcTemplate" ref="jdbcTemplate"/>
</bean>
<!-- 4.事务管理器，依赖于数据源 -->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"/>
</bean>
<!-- 5.注册事务管理器驱动 -->
<tx:annotation-driven transaction-manager="transactionManager"/>
</beans>
Student类
package demo666;
public class Student {
//学生ID
private Integer id;
//学生姓名
private String username;
//学生密码
private String password;
//学生班级
private String course;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getCourse() {
return course;
}
public void setCourse(String course) {
this.course = course;
}
}
StudentDao接口
package demo666;
import demo666.Student;
import java.util.List;
public interface StudentDao {
//查询所有账户
public List<Student> findAllStudent();
}
StudentDaoImpl实现类
package demo666;
import demo666.StudentDao;
import demo666.Student;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import java.util.List;
public class StudentDaoImpl implements StudentDao {
// 声明JdbcTemplate属性及其setter方法
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
// 查询所有用户信息
public List<Student> findAllStudent() {
// 定义SQL语句
String sql = "select * from student";
// 创建一个新的BeanPropertyRowMapper对象
RowMapper<Student> rowMapper =
new BeanPropertyRowMapper<Student>(Student.class);
// 执行静态的SQL查询，并通过RowMapper返回结果
return this.jdbcTemplate.query(sql, rowMapper);
}
}
运行结果
调试结果
不报错 也不往下进行下面的过程 直接就结束 这是怎么回事呢 求解答！
Scanner sca = new Scanner(System.in);
String name = sca.nextLine();
// 加载配置文件
ApplicationContext applicationContext = new
ClassPathXmlApplicationContext("applicationContext-student.xml");
// 获取AccountDao实例
这一块多加几个print或者debug模式运行看看。加几个断点
可能是你获取学生列表的时候获取为空，可以对这个列表进行判断，如果为空打印一行日志看看
获取到的student列表为空就直接退出了
不知道你这个问题是否已经解决, 如果还没有解决的话:- 这篇文章：spring占位符无法替换的报错排查 也许能够解决你的问题，你可以看下
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