我一直试图通过应用程序中嵌入的Apache Tomcat
使我的Java应用程序托管一个网页(一个HTML页面,而不是JSP)。我在Maven
上使用NetBeans IDE 8.0.2.
构建系统由于某种原因,Tomcat
拒绝识别我在应用程序中放置的index.html
页面,尽管多次尝试并创建各种类型像WEB-INF
这样的文件夹。但它仍然向我发出404
错误。
以下是我在项目中设置的一些相关代码(某些代码已被省略,但与情况无关):
1。 MainApplication.java - 启动Tomcat
import java.util.Calendar;
import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;
import java.io.*;
import java.util.Optional;
import org.apache.catalina.startup.Tomcat;
public class MainApplication{
public static final Optional<String> port = Optional.ofNullable(System.getenv("PORT"));
public static void main(String[] args) throws Exception {
String contextPath = "/";
String appBase = ".";
Tomcat tomcat = new Tomcat();
tomcat.setPort(Integer.valueOf(port.orElse("8080")));
tomcat.getHost().setAppBase(appBase);
tomcat.addWebapp(contextPath, appBase);
tomcat.start();
tomcat.getServer().await();
}
}
2。 ShuttleServlet.java
@WebServlet(
name = "ShuttleServlet", urlPatterns = {"/shuttle"}
)
public class ShuttleServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// Code to interact with application to be added later
}
3。目录结构
- src
|
- main
|
- resources
- webapp
|
* index.html
* scripts.js
4。 Maven 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.example</groupId>
<artifactId>TransportApp</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-core</artifactId>
<version>${tomcat.version}</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-logging-juli</artifactId>
<version>${tomcat.version}</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-jasper</artifactId>
<version>${tomcat.version}</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-jasper</artifactId>
<version>${tomcat.version}</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-jasper-el</artifactId>
<version>${tomcat.version}</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-jsp-api</artifactId>
<version>${tomcat.version}</version>
</dependency>
<dependency>
<groupId>jstl</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>6.0.5</version>
</dependency>
</dependencies>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
<tomcat.version>7.0.57</tomcat.version>
</properties>
<build>
<finalName>TransportApp</finalName>
<resources>
<resource>
<directory>src/main/webapp</directory>
<targetPath>META-INF/resources</targetPath>
</resource>
</resources>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.3.2</version>
<inherited>true</inherited>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<finalName>TransportApp-${project.version}</finalName>
<archive>
<manifest>
<mainClass>com.example.TransportApp.MainApplication</mainClass>
</manifest>
</archive>
</configuration>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
5。 Tomcat控制台日志
Dec 04, 2016 3:09:24 AM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-bio-8080"]
Dec 04, 2016 3:09:24 AM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Tomcat
Dec 04, 2016 3:09:24 AM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: Apache Tomcat/7.0.57
Dec 04, 2016 3:09:24 AM org.apache.catalina.startup.ContextConfig getDefaultWebXmlFragment
INFO: No global web.xml found
Dec 04, 2016 3:09:25 AM org.apache.catalina.util.SessionIdGenerator createSecureRandom
INFO: Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [170] milliseconds.
Dec 04, 2016 3:09:25 AM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["http-bio-8080"]
所有这些导致404
尽管有多次尝试和现在已删除的文件夹仍然存在。我希望所有这些都有助于找到罪魁祸首。
答案 0 :(得分:2)
问题的根本原因:
问题在于您的Launcher类。在启动器类中,下面的代码行试图查看web-app的同一目录,这实际上是不正确的。
tomcat.addWebapp(contextPath, appBase);
由于appBase设置为&#34;。&#34;,这意味着它将尝试查看启动器类所在的同一目录。
<强>解决方案强>
尝试使用下面的代码,这很容易理解。您必须将webApp路径正确设置为tomcat上下文,以便在运行时点击该路径时识别它。
String webappDirLocation = "src/main/webapp/";
Tomcat tomcat = new Tomcat();
//The port that we should run on can be set into an environment variable
//Look for that variable and default to 8080 if it isn't there.
String webPort = System.getenv("PORT");
if(webPort == null || webPort.isEmpty()) {
webPort = "8080";
}
tomcat.setPort(Integer.valueOf(webPort));
StandardContext ctx = (StandardContext) tomcat.addWebapp("/", new File(webappDirLocation).getAbsolutePath());
System.out.println("configuring app with basedir: " + new File("./" + webappDirLocation).getAbsolutePath());
// Declare an alternative location for your "WEB-INF/classes" dir
// Servlet 3.0 annotation will work
File additionWebInfClasses = new File("target/classes");
WebResourceRoot resources = new StandardRoot(ctx);
resources.addPreResources(new DirResourceSet(resources, "/WEB- INF/classes", additionWebInfClasses.getAbsolutePath(), "/"));
ctx.setResources(resources);
tomcat.start();
tomcat.getServer().await();
答案 1 :(得分:1)
第一个maven是旧的,改为使用Gradle;)
每个进程都有一个工作目录,当File是相对的时,它将被解释为与之相关。 这一点很重要,因为除非您将其用于简单测试,否则开发和部署之间的目录结构可能不同。
如果您将程序构建为jar文件,则“./src/main/webapp”之类的相对URL很可能无法正常工作,因为“src / main”会消失,只会留下“webapp”(如同你建立一个WAR文件。)
构建像Gradle(和Maven)这样的工具,IDE在编译后有一个“processResource”步骤,它将资源复制到一个(通常)属于类路径的位置。由于除非您正在构建Web应用程序,否则不会复制/ main / resources / webapp,因此在IDE外部运行代码时会遇到问题。
就个人而言,我建议您构建一个已经有嵌入式tomcat的Spring启动应用程序。在Spring Boot中.html文件是从类路径(main / resources / static)加载的,因为资源在类路径中,所以它们在开发和部署中都具有相同的位置(因为资源处理)。
对于Spring boot Web应用程序,您将需要一个依赖项 org.springframework.boot:弹簧引导起动网:1.4.1.RELEASE 所以你的 build.gradle 文件看起来像这样(你可以在IDE中创建一个Gradle项目)
apply plugin: 'java'
sourceCompatibility = 1.8
repositories {
mavenCentral()
}
dependencies {
compile("org.springframework.boot:spring-boot-starter-web:1.4.1.RELEASE")
}
您的Java Main看起来像这样
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class Main {
public static void main(String[] args) {
SpringApplication.run(Main.class, args);
}
}
把你的.html文件放在/ main / resources / static中 - 完成!! 你可能会猜到Spring启动内部有很多魔法,而且你不必编写任何代码的原因是因为Spring Boot团队选择了非常好的默认值,但是如果你需要,不要担心以后更高级这也是可能的。如果你需要服务器端渲染,你可以添加org.springframework.boot:spring-boot-starter-thymeleaf:{version},并将你的模板放到/ resources / templates中,然后你去。那里有很多很好的教程。
Spring在servlet之上也有一个更好的抽象,称为控制器,再次提供大量文档。
答案 2 :(得分:0)
尝试使用SpringBoot!哪个有嵌入式tomcat, 使用web和thymeleaf依赖, thymeleaf是模板引擎,可以识别您的网页。 尝试从这个网站http://start.spring.io/创建一个spring boot项目,这是一个spring初始化程序,用于创建一个带有spring boot的maven项目。添加web和thymeleaf依赖项并生成项目。 将项目作为maven项目导入IDE中的项目, 或使用Spring工具套装
DemoApplication.java
@Controller
@SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
@RequestMapping(value = "/homepage" , method = RequestMethod.GET )
public String sample()
{
return "home";
}
}
的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.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.2.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>1.7</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<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>
home.html的
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"></meta>
<title>HomePage</title>
</head>
<body>
<h1>MY Spring Boot Home Page</h1>
</body>
</html>
答案 3 :(得分:0)
我认为您缺少主机名部分以及maven构建步骤。尝试使用maven命令和java -jar命令运行。尝试以下看看是否有效。
public static final Optional<String> PORT = Optional.ofNullable(System.getenv("PORT"));
public static final Optional<String> HOSTNAME = Optional.ofNullable(System.getenv("HOSTNAME"));
public static void main(String[] args) throws Exception {
String contextPath = "/" ;
String appBase = ".";
Tomcat tomcat = new Tomcat();
tomcat.setPort(Integer.valueOf(PORT.orElse("8080") ));
tomcat.setHostname(HOSTNAME.orElse("localhost"));
tomcat.getHost().setAppBase(appBase);
tomcat.addWebapp(contextPath, appBase);
tomcat.start();
tomcat.getServer().await();
}
执行以下步骤:(您需要在本地安装maven) 打开cmd,转到源文件夹,pom文件所在的位置。执行以下命令
mvn compile
然后按回车
mvn package。
然后按回车
cd目标 然后按回车
java -jar [你的应用名称] .jar(在目标文件夹中你会看到一个jar文件,把它的名字放在这里)
从命令运行后,您可以通过浏览器中的localhost浏览。 Netbeans跑了给我404.我这样解决了。
您可以查看此链接“运行Web应用程序部件”: http://www.oracle.com/webfolder/technetwork/tutorials/obe/java/basic_app_embedded_tomcat/basic_app-tomcat-embedded.html
答案 4 :(得分:0)
我不知道你是否解决了这里描述的问题。
我希望这会有助于其他人。
为了嵌入Tomcat,我使用了一个插件而不是依赖项:dowing so,所以,不需要主类和代码来创建一个tomcat实例。
以下是POM必须包含的内容:
<project ...>
.....
<dependencies>
<!-- no need of any --->
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.3</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.2</version>
<configuration>
<server>localhost</server>
<path>/${project.build.finalName}</path>
</configuration>
</plugin>
</plugins>
</build>
</project>
以下是web.xml的示例
<web-app id="WebApp_ID" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>My Test App</display-name>
<description>A test app</description>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
</welcome-file-list>
<session-config>
<session-timeout>30</session-timeout>
</session-config>
</web-app>
您既不需要主类也不需要代码(如问题中所示)。 我们当然需要显示页面,所以这里有一个index.html的例子(如web.xml中所述):
<html>
<body>
<h2>Hello World!</h2>
</body>
</html>
在eclipse中:右键单击,运行“运行配置”,在“Maven Build”下添加“新启动配置”,设置Base目录并在“Goals”下输入:tomcat7:run。 而已! 你会得到:
[INFO] Scanning for projects...
[INFO]
[INFO] --------------------------------------------------------------------
[INFO] Building rest-with-jersey Maven Webapp 0.0.1-SNAPSHOT
[INFO] --------------------------------------------------------------------
[INFO]
[INFO] >>> tomcat7-maven-plugin:2.2:run (default-cli) > process-classes @ rest-with-jersey >>>
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ rest-with-jersey ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ rest-with-jersey ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] <<< tomcat7-maven-plugin:2.2:run (default-cli) < process-classes @ rest-with-jersey <<<
[INFO]
[INFO] --- tomcat7-maven-plugin:2.2:run (default-cli) @ rest-with-jersey ---
[INFO] Running war on http://localhost:8080/rest-with-jersey
[INFO] Using existing Tomcat server configuration at /common/home/$$$/$$$$/lnx/workspace/rest-with-jersey/target/tomcat
[INFO] create webapp with contextPath: /rest-with-jersey
Sep 11, 2017 4:03:07 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-bio-8080"]
Sep 11, 2017 4:03:07 PM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Tomcat
Sep 11, 2017 4:03:07 PM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: Apache Tomcat/7.0.47
Sep 11, 2017 4:03:09 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["http-bio-8080"]
In a browser with http://localhost:8080/rest-with-jersey/ you get the " Hello World!".