Spring Boot Hello World(Thymeleaf)示例

這是一個Spring Boot Web應用示例,使用嵌入式Tomcat + Thymeleaf模板引擎,並將其作爲可執行JAR文件。

使用的相關技術:

  • Spring Boot 1.4.2.RELEASE
  • Spring 4.3.4.RELEASE
  • Thymeleaf 2.1.5.RELEASE
  • Tomcat Embed 8.5.6
  • Maven 3
  • Java 8

1. 項目目錄

手動創建以下文件夾目錄結構:
Spring

2. 項目依賴

聲明 spring-boot-starter-thymeleaf以獲得開發Spring + Thymeleaf Web應用程序所需的任何程序類庫。

參考如下 pom.xml 文件 -

<?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>

    <artifactId>spring-boot-web-thymeleaf</artifactId>
    <packaging>jar</packaging>
    <name>Spring Boot Web Thymeleaf 示例</name>
    <description>Spring Boot Web Thymeleaf 示例描述</description>
    <url>http://www.yiibai.com</url>
    <version>1.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.2.RELEASE</version>
    </parent>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>

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

        <!-- hot swapping, disable cache for template, enable live reload -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>

        <!-- Optional, for bootstrap -->
        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>bootstrap</artifactId>
            <version>3.3.7</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <!-- Package as an executable jar/war -->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

顯示項目依賴關係:

提示: spring-boot-devtools
這個spring-boot-devtools有助於禁用緩存並啓用熱插拔,以便開發人員總是看到最後的更改。 有利於發展。 閱讀這篇 - Spring Boot - 開發工具。嘗試修改Thymeleaf模板或屬性文件,刷新瀏覽器以查看更改立即生效。

3. Spring Boot

使用[@SpringBootApplication](https://github.com/SpringBootApplication "@SpringBootApplication")進行註釋。 運行此類來啓動Spring Boot Web應用程序。

SpringBootWebApplication.java

package com.yiibai;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootWebApplication {

    public static void main(String[] args) throws Exception {
        SpringApplication.run(SpringBootWebApplication.class, args);
    }

}

一個簡單的Spring控制器類: WelcomeController.java 代碼如下 -

package com.yiibai;

import java.util.Map;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class WelcomeController {

    // inject via application.properties
    @Value("${welcome.message:test}")
    private String message = "Hello World";

    @RequestMapping("/")
    public String welcome(Map<String, Object> model) {
        model.put("message", this.message);
        return "welcome";
    }

}

4. Thymeleaf +資源+靜態文件

對於Thymeleaf模板文件,放入 src/main/resources/templates/ 目錄下, src/main/resources/templates/welcome.html 文件代碼如下 -

<!DOCTYPE HTML>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<title>Spring Boot Thymeleaf Hello World示例</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

<link rel="stylesheet" type="text/css"
    href="webjars/bootstrap/3.3.7/css/bootstrap.min.css" />

<link rel="stylesheet" th:href="@{/css/main.css}"
    href="../../css/main.css" />

</head>
<body>

    <nav class="navbar navbar-inverse">
        <div class="container">
            <div class="navbar-header">
                <a class="navbar-brand" href="#">Spring Boot</a>
            </div>
            <div id="navbar" class="collapse navbar-collapse">
                <ul class="nav navbar-nav">
                    <li class="active"><a href="#">首頁</a></li>
                    <li><a href="#about">關於</a></li>
                </ul>
            </div>
        </div>
    </nav>

    <div class="container">

        <div class="starter-template">
            <h1>Spring Boot Web Thymeleaf示例</h1>
            <h2>
                <span th:text="'Message: ' + ${message}"></span>
            </h2>
        </div>

    </div>
    <!-- /.container -->

    <script type="text/javascript"
        src="webjars/bootstrap/3.3.7/js/bootstrap.min.js"></script>

</body>
</html>
`

對於靜態文件,如CSS或Javascript,將它們放入 /src/main/resources/static/ 目錄, /src/main/resources/static/css/main.css文件代碼如下 -

h1{
    font-size: 20pt;
}
h2{
    font-size: 16pt;
}

對於屬性文件,放入 /src/main/resources/ 目錄中, /src/main/resources/application.properties 文件中的代碼內容如下 -

welcome.message: Hello, Spring Boot

注意: 閱讀此Spring Boot服務靜態內容以瞭解資源映射。

5. 運行演示

啓動Spring Boot Web應用程序,使用Maven命令:mvn spring-boot:run,運行結果輸出結果如下 -

F:\worksp\springboot\spring-boot-web-thymeleaf > mvn spring-boot:run
... ....

Downloaded: http://repo.maven.apache.org/maven2/commons-io/commons-io/1.3.2/commons-io-1.3.2.jar (86 KB at 1.4 KB/sec)
Downloaded: http://repo.maven.apache.org/maven2/org/apache/commons/commons-compress/1.9/commons-compress-1.9.jar (370 KB at 5.9 KB/sec)
Downloaded: http://repo.maven.apache.org/maven2/org/jdom/jdom/1.1/jdom-1.1.jar (150 KB at 2.3 KB/sec)
Downloaded: http://repo.maven.apache.org/maven2/org/sonatype/sisu/sisu-guice/2.1.7/sisu-guice-2.1.7-noaop.jar (461 KB at 6.8 KB/sec)
Downloaded: http://repo.maven.apache.org/maven2/com/google/guava/guava/18.0/guava-18.0.jar (2204 KB at 15.6 KB/sec)
[INFO] Attaching agents: []

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
::Spring Boot::       (v1.4.2.RELEASE)

2017-03-22 02:45:51.162  INFO 5284 --- [  restartedMain] com.yiibai.SpringBootWebApplication      : Starting SpringBootWebApplication on MY-PC with PID 5284 (F:\worksp\springboot\web-thymeleaf\target\classes started by Administrator in F:\worksp\springboot\web-thymeleaf)
2017-03-22 02:45:51.162  INFO 5284 --- [  restartedMain] com.yiibai.SpringBootWebApplication      : No active profile set, falling back to default profiles: default
2017-03-22 02:45:51.740  INFO 5284 --- [  restartedMain] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot[email protected]e33d3c1: startup date [Wed Mar 22 02:45:51 CST 2017]; root of context hierarchy
2017-03-22 02:45:57.190  INFO 5284 --- [  restartedMain] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-03-22 02:45:57.221  INFO 5284 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service Tomcat
2017-03-22 02:45:57.221  INFO 5284 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.6
2017-03-22 02:45:57.471  INFO 5284 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2017-03-22 02:45:57.471  INFO 5284 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 5731 ms
2017-03-22 02:45:57.815  INFO 5284 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2017-03-22 02:45:57.830  INFO 5284 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-03-22 02:45:57.846  INFO 5284 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-03-22 02:45:57.846  INFO 5284 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-03-22 02:45:57.846  INFO 5284 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2017-03-22 02:45:58.867  INFO 5284 --- [  restartedMain] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot[email protected]e33d3c1: startup date [Wed Mar 22 02:45:51 CST 2017]; root of context hierarchy
2017-03-22 02:45:59.115  INFO 5284 --- [  restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/]}" onto public java.lang.String com.yiibai.WelcomeController.welcome(java.util.Map<java.lang.String, java.lang.Object>)
2017-03-22 02:45:59.115  INFO 5284 --- [  restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2017-03-22 02:45:59.115  INFO 5284 --- [  restartedMain] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2017-03-22 02:45:59.193  INFO 5284 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-03-22 02:45:59.193  INFO 5284 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-03-22 02:45:59.286  INFO 5284 --- [  restartedMain] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-03-22 02:46:10.440  INFO 5284 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
2017-03-22 02:46:10.721  INFO 5284 --- [  restartedMain] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2017-03-22 02:46:14.581  INFO 5284 --- [  restartedMain] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-03-22 02:46:14.597  INFO 5284 --- [  restartedMain] com.yiibai.SpringBootWebApplication      : Started SpringBootWebApp

運行成功後,打瀏覽器訪問: http://localhost:8080 ,沒有問題應該會看到以下輸出頁面 -

Spring

6. 構建可執行JAR

打包項目以創建可執行的JAR文件。使用Maven命令:mvn clean package

F:\worksp\springboot\spring-boot-web-thymeleaf> java -jar target/spring-boot-web-thymeleaf-1.0.jar

運行成功後,打瀏覽器再次訪問: http://localhost:8080 ,沒有問題應該會看到以下輸出頁面 -

Spring