Spring Boot 简明教程
Spring Boot - Tomcat Deployment
通过使用 Spring Boot 应用程序,我们可以在 web 服务器中创建 war 文件进行部署。在此章节中,您将学习如何创建一个 WAR 文件,并在 Tomcat web 服务器中部署 Spring Boot 应用程序。
Spring Boot Servlet Initializer
传统的部署方式是让 Spring Boot 应用程序 @SpringBootApplication 类继承 SpringBootServletInitializer 类。Spring Boot Servlet Initializer 类文件允许您在启动应用程序时使用 Servlet Container 进行配置。
JAR 文件部署的 Spring Boot 应用程序类文件的代码如下 -
package com.tutorialspoint.demo;
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);
}
}
我们需要继承类 SpringBootServletInitializer 来支持 WAR 文件部署。Spring Boot 应用程序类文件的代码如下 -
package com.tutorialspoint.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
@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);
}
}
Setting Main Class
在 Spring Boot 中,我们需要在构建文件中提及应启动的主类。为此,您可以使用以下代码片断 -
对于 Maven,在 pom.xml 属性中添加启动类,如下所示 -
<start-class>com.tutorialspoint.demo.DemoApplication</start-class>
对于 Gradle,在 build.gradle 文件中添加主类名,如下所示:
mainClassName="com.tutorialspoint.demo.DemoApplication"
Update packaging JAR into WAR
我们必须使用以下代码片断将打包 JAR 更新为 WAR:
对于 Maven,在 pom.xml 中将打包添加为 WAR,如下所示:
<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:
apply plugin: ‘war’
apply plugin: ‘application’
现在,让我们编写一个简单的 Rest 端点以返回字符串“Hello World from Tomcat”。要编写 Rest 端点,我们需要将 Spring Boot web starter 依赖项添加到构建文件中。
对于 Maven,使用以下代码在 pom.xml 中添加 Spring Boot starter 依赖项:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
对于 Gradle,使用以下代码在 build.gradle 中添加 Spring Boot starter 依赖项:
dependencies {
compile('org.springframework.boot:spring-boot-starter-web')
}
现在,使用以下代码,在 Spring Boot 应用程序类文件中编写一个简单的 Rest 端点:
package com.tutorialspoint.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.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";
}
}
Packaging your Application
现在,使用 Maven 和 Gradle 命令来打包应用程序,并创建一个 WAR 文件以部署到 Tomcat 服务器,如下所示:
对于 Maven,使用命令 mvn package 来打包应用程序。然后,将创建 WAR 文件,你可以在目标目录中找到它,如下面的屏幕截图所示:
对于 Gradle,使用命令 gradle clean build 来打包应用程序。然后,你的 WAR 文件将被创建,你可以在 build/libs 目录中找到它。仔细观察此处给出的屏幕截图,以更好地理解:
Deploy into Tomcat
现在,运行 Tomcat 服务器,并将 WAR 文件部署在 webapps 目录下。仔细观察此处显示的屏幕截图,以更好地理解:
成功部署后,在 Web 浏览器 http://localhost:8080/demo-0.0.1-SNAPSHOT/ 中输入 URL,你会看到输出的外观如下面给出的屏幕截图所示:
为此目的的完整代码如下所示:
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.tutorialspoint</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.tutorialspoint.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>
build.gradle
buildscript {
ext {
springBootVersion = '1.5.8.RELEASE'
}
repositories {
mavenCentral()
}
dependencies {
classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
}
}
apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'org.springframework.boot'
apply plugin: 'war'
apply plugin: 'application'
group = 'com.tutorialspoint'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = 1.8
mainClassName = "com.tutorialspoint.demo.DemoApplication"
repositories {
mavenCentral()
}
dependencies {
compile('org.springframework.boot:spring-boot-starter-web')
testCompile('org.springframework.boot:spring-boot-starter-test')
}
Spring Boot 主应用程序类文件的代码如下 -
package com.tutorialspoint.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.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";
}
}