Spring Boot Servlet初始化程序
传统的部署方式是使Spring Boot应用程序@SpringBootApplication类扩展SpringBootServletInitializer类。SpringBootServletInitializer类文件允许在使用Servlet容器启动时配置应用程序。
下面给出了用于JAR文件部署的Spring Boot应用程序类文件的代码 -
代码语言:javascript复制import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
需要扩展类SpringBootServletInitializer以支持WAR文件部署。Spring Boot应用程序类文件的代码如下 -
代码语言:javascript复制@SpringBootApplication
public class DemoApplication extends SpringBootServletInitializer {
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
return application.sources(DemoApplication.class);
}
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
设置Main类
在Spring Boot中,需要在构建文件中指定启动的主类。对于Maven,在pom.xml属性中添加start类,如下所示 -
代码语言:javascript复制<start-class>com.test.demo.DemoApplication</start-class>
对于Gradle,在build.gradle中添加主类名,如下所示 -
代码语言:javascript复制mainClassName="com.test.demo.DemoApplication"
将打包JAR更新为WAR
使用以下代码将包装JAR更新为WAR。
对于Maven,在pom.xml 中将包装添加为WAR,如下所示 -
代码语言:javascript复制<packaging>war</packaging>
对于Gradle,在build.gradle 中添加应用程序插件和war插件,如下所示 -
代码语言:javascript复制apply plugin: 'war'
apply plugin: 'application'
对于GradlNow,编写一个简单的Rest端点来返回字符串:"Hello World from Tomcat"。要编写Rest端点,需要将Spring Boot Web starter依赖项添加到构建文件中。
对于Maven,使用如下所示的代码在pom.xml 中添加Spring Boot启动程序依赖项 -
代码语言:javascript复制<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
对于Gradle,使用如下所示的代码在build.gradle 中添加Spring Boot starter依赖项 -
代码语言:javascript复制dependencies {
compile('org.springframework.boot:spring-boot-starter-web')
}
现在,使用如下所示的代码在Spring Boot Application类文件中编写一个简单的Rest端点 -
代码语言:javascript复制import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.support.SpringBootServletInitializer;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@SpringBootApplication
@RestController
public class DemoApplication extends SpringBootServletInitializer {
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
return application.sources(DemoApplication.class);
}
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
@RequestMapping(value = "/")
public String hello() {
return "Hello World from Tomcat";
}
}
打包应用程序
现在,使用Maven和Gradle命令创建一个WAR文件以部署到Tomcat服务器中,以打包应用程序,如下所示。
对于Maven,使用命令mvn package打包应用程序。然后创建WAR文件,可以在目标目录中找到它,如下面给出的屏幕截图所示 -
对于Gradle,使用命令gradle clean build打包应用程序。然后,将创建WAR文件,可以在build/libs目录下找到它。观察此处给出的屏幕截图以便更好地理解 -
部署到Tomcat
现在,运行Tomcat服务器,并在webapps目录下部署WAR文件。观察此处显示的屏幕截图以便更好地理解 -
成功部署后,点击网页浏览器中的URL => http://localhost:8080/demo-0.0.1-SNAPSHOT/,观察输出结果如下图所示 -
完整代码
文件:pom.xml -
代码语言:javascript复制<?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.test</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.8.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<start-class>com.test.demo.DemoApplication</start-class>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
Spring Boot应用程序类文件的代码如下 -
代码语言:javascript复制import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.support.SpringBootServletInitializer;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@SpringBootApplication
@RestController
public class DemoApplication extends SpringBootServletInitializer {
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
return application.sources(DemoApplication.class);
}
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
@RequestMapping(value = "/")
public String hello() {
return "Hello World from Tomcat";
}
}