java：包org.springframework.dao和org.springframework.jdbc.core不存在

Question

刚刚开始处理Maven和Spring。当我尝试创建DAO和ResultSet然后运行应用程序时，抛出errors:

Error:(4, 31) java: package org.springframework.dao does not exist
Error:(5, 37) java: package org.springframework.jdbc.core does not exist
Error:(5, 43) java: package org.springframework.context.support does not exist

您能否建议可能是什么问题？不是这样配置的依赖项或其他内容吗？

我的pom.xml包含

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>5.2.1.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>5.2.1.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>javax.inject</groupId>
        <artifactId>javax.inject</artifactId>
        <version>1</version>
    </dependency>
    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-dbcp2</artifactId>
        <version>2.7.0</version>
    </dependency>
    <dependency>
        <groupId>postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <version>9.1-901-1.jdbc4</version>
    </dependency>
    <dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <version>42.2.8</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.2.1.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jdbc</artifactId>
        <version>2.2.1.RELEASE</version>
    </dependency>
</dependencies>
<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.8.1</version>
            <configuration>
                <source>8</source>
                <target>8</target>
            </configuration>
        </plugin>
    </plugins>
</build>

DAO类和应用程序附在此处1和2

Answer 1

如果您不必开发旧式的Spring项目，则可以尝试使用spring-boot来简化配置。您可以在此处创建一个有效的项目模板：

https://start.spring.io/