spring与jndi(数据库连接)SpringBoot打war包并整合jsp

spring与jndi(数据库连接)SpringBoot打war包并整合jsp，这里的jndi指的是jdbc连接，不是其他的。有传统servlet+spring和springboot的jndi连接操作，并整合jsp和thymeleaf。下面我以他们两个为例子演示。

一、servlet+spring下的jndi

一个普通servlet项目整合spring 5.14后，在运行的tomcat/conf/context.xml的Context标签里配置jndi：

	<Resource name="localhostJndiName" 
		validationQuery="select 1"
        auth="Container" 
        type="javax.sql.DataSource"
        driverClassName="com.mysql.jdbc.Driver"     
        url=" jdbc:mysql://localhost:3306/test?useSSL=false&amp;useUnicode=true&amp;characterEncoding=utf8&amp;serverTimezone=GMT" 
        username="root" 
        password="123456" maxActive="60" maxIdle="1"/>

注入xml中配置jndi的bean

    <bean id="jndiObjectFactoryBean" class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName">
            <!-- Weblogic数据源配置格式
            <value>jndi_name</value> -->
            <!-- Tomcat数据源配置格式 -->
            <value>java:comp/env/localhostJndiName</value>
        </property>
    </bean>

获取DataSource进行数据操作

@Configuration
@Controller
public class WebController {
    @Autowired
    private JndiObjectFactoryBean jndiObjectFactoryBean;

    @Bean
    public DataSource dataSource() {
        return (DataSource) jndiObjectFactoryBean.getObject();
    }

    @GetMapping(value = {"/index", ""})
    public String index() {
        try {
            Connection connection = dataSource().getConnection();
            PreparedStatement preparedStatement = connection.prepareStatement("select * from opr_cluster limit 1");
            ResultSet resultSet = preparedStatement.executeQuery();
            while (resultSet.next()) {
                System.out.println(
                        resultSet.getString(1) + " " +
                                // resultSet.getString(2) + " " +
                                resultSet.getString(3) + " " +
                                resultSet.getString(4) + " " +
                                resultSet.getString(5) + " " +
                                resultSet.getString(6)
                );
            }
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        return "index";
    }
}

效果：

可进一步对DataSource注入mybatis、hibernate等框架进行SQL操作！

二、在springboot中进行jndi操作

是不是有点奇怪？不奇怪，我就遇到甲方要求springboot打包war进行部署，数据源要求使用jndi。爸爸最大，我们得搞出来呢。
首先创建一个普通的springboot项目，重写springboot servlet的初始化SpringBootServletInitializer

@SpringBootApplication
public class DemoApplication extends SpringBootServletInitializer {
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder builder) {
        return builder.sources(DemoApplication.class);
    }
}

修改pom.xml，主要是把打包改为war，插件设置无xml，引入数据库。

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>top.lingkang</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
    <packaging>war</packaging>

    <properties>
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <spring-boot.version>2.3.7.RELEASE</spring-boot.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>2.3.7.RELEASE</version>
                <configuration>
                    <mainClass>top.lingkang.demo.DemoApplication</mainClass>
                </configuration>
                <executions>
                    <execution>
                        <id>repackage</id>
                        <goals>
                            <goal>repackage</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <configuration>
                    <warName>springboot-jndi</warName>
                    <!-- 不外部打包 web.xml -->
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

编写一个controller

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jndi.JndiObjectFactoryBean;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

/**
 * @author lingkang
 * Created by 2021/12/20
 */
@Configuration
@RestController
public class WebController {
    @Bean
    public JndiObjectFactoryBean jndiObjectFactoryBean() {
        JndiObjectFactoryBean bean = new JndiObjectFactoryBean();
        // tomcat一定要配置这个数据源
        bean.setJndiName("java:comp/env/localhostJndiName");
        return bean;
    }

    @Autowired
    private JndiObjectFactoryBean jndiObjectFactoryBean;

    @Bean
    public DataSource dataSource() {
        return (DataSource) jndiObjectFactoryBean.getObject();
    }

    @Autowired
    private DataSource dataSource;

    @GetMapping()
    public Object index() {
        try {
            Connection connection = dataSource.getConnection();
            PreparedStatement preparedStatement = connection.prepareStatement("select * from opr_cluster limit 1");
            ResultSet resultSet = preparedStatement.executeQuery();
            String result = "empty";
            while (resultSet.next()) {
                result = String.format("%s--%s--%s--%s",
                        resultSet.getString(1),
                        resultSet.getString(3),
                        resultSet.getString(4),
                        resultSet.getString(5)
                );
                System.out.println(result);
            }
            return result;
        } catch (Exception e) {
            e.printStackTrace();
            return e.getMessage();
        }
    }
}

然后选择配置了jndi数据源的tomcat来运行它，数据库配置参考第一节的配置内容。



效果：

mvn package能够正常打war包，并且丢war能正常运行。

2.1 添加jsp测试

我们添加jsp测试会如何：
先添加jsp需要的依赖

<!--用于jsp页面 jstl表达式-->
 <dependency>
     <groupId>javax.servlet</groupId>
     <artifactId>jstl</artifactId>
     <version>1.2</version>
 </dependency>
 <!--用于编译jsp-->
 <dependency>
     <groupId>org.apache.tomcat.embed</groupId>
     <artifactId>tomcat-embed-jasper</artifactId>
 </dependency>

application.properties

spring.mvc.view.prefix=/WEB-INF/
spring.mvc.view.suffix=.jsp

改造控制类

	// 将类注解改为@Controller
	@Configuration
	@Controller
	public class WebController {
	// ...
    @Autowired
    private HttpServletRequest request;

    @GetMapping()
    public Object index() {
        String result = "empty";
        try {
            Connection connection = dataSource.getConnection();
            PreparedStatement preparedStatement = connection.prepareStatement("select * from opr_cluster limit 1");
            ResultSet resultSet = preparedStatement.executeQuery();
            while (resultSet.next()) {
                result = String.format("%s--%s--%s--%s",
                        resultSet.getString(1),
                        resultSet.getString(3),
                        resultSet.getString(4),
                        resultSet.getString(5)
                );
                System.out.println(result);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        request.setAttribute("result",result);
        return "index";
    }

webapps/WEB-INF/index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>lingkang</title>
</head>
<body>
查询结果：<br>
<%
    out.println(request.getAttribute("result"));
%>
</body>
</html>

设置一下jsp解析路径，否则找不到解析的template

运行它，效果如下：

2.2 使用thymeleaf

基于2.1，将依赖改为

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>

application.properties

# 应用名称
spring.application.name=demo
# 应用服务 WEB 访问端口
server.port=8080

spring.thymeleaf.prefix=classpath:/templates/

添加resources/templates/index.html

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
查询结果：[[${result}]]
</body>
</html>

tomcat运行项目查看

至此，spring常见整合完毕，特别是整合jsp，jsp挺经典的emm，可以在jsp里写java代码666，觉得不错就点个赞吧！