在 Apache Tomcat 8 上调用 RESTful 服务返回 404答案

【问题标题】：Calling RESTful services on Apache Tomcat 8 returns 404在 Apache Tomcat 8 上调用 RESTful 服务返回 404
【发布时间】：2016-02-22 01:15:26
【问题描述】：

我有带有动态 Web 项目和 Maven 的 Eclipse Mars。我为 Eclipse 安装和配置了 Tomcat 8 服务器。我正在尝试对其运行 REST 请求。 Eclipse 中没有编译错误或问题。 tomcat 启动时没有严重错误。似乎所有的罐子都正确设置了（我之前为此进行了一场艰苦的战斗）。我所有的 java 包都在 src 文件夹中。 Tomcat 成功地从 web.xml 加载 Java 类 - 我已经检查过了 localhost:8080/manager/jmxproxy/?qry=%3Aj2eeType=Servlet%2c

我有 3 个示例 servlet - 它们都不起作用！

编辑：问题不在于我的代码，而在于 Eclipse！看看答案...

这是 Tomcat 启动日志：

??? 19, 2015 9:20:11 PM org.apache.tomcat.util.digester.SetPropertiesRule begin
WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:AutomationWeb' did not find a matching property.
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Server version:        Apache Tomcat/8.0.28
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Server built:          Oct 7 2015 18:25:21 UTC
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Server number:         8.0.28.0
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: OS Name:               Windows 7
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: OS Version:            6.1
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Architecture:          amd64
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Java Home:             C:\Program Files\Java\jre7
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: JVM Version:           1.7.0_79-b15
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: JVM Vendor:            Oracle Corporation
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: CATALINA_BASE:         C:\RPI automation\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: CATALINA_HOME:         C:\RPI automation\apache-tomcat-8.0.28
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Command line argument: -Dcatalina.base=C:\RPI automation\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Command line argument: -Dcatalina.home=C:\RPI automation\apache-tomcat-8.0.28
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Command line argument: -Dwtp.deploy=C:\RPI automation\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\webapps
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Command line argument: -Djava.endorsed.dirs=C:\RPI automation\apache-tomcat-8.0.28\endorsed
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.VersionLoggerListener log
INFO: Command line argument: -Dfile.encoding=Cp1252
??? 19, 2015 9:20:11 PM org.apache.catalina.core.AprLifecycleListener lifecycleEvent
INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Java\jre7\bin;C:\windows\Sun\Java\bin;C:\windows\system32;C:\windows;C:\windows\system32;C:\windows;C:\windows\System32\Wbem;C:\windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\ThinkPad\Bluetooth Software\;C:\Program Files\ThinkPad\Bluetooth Software\syswow64;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Intel\WirelessCommon\;C:\Program Files (x86)\Lenovo\Access Connections\;C:\Program Files (x86)\IBM\Personal Communications\;C:\Program Files (x86)\IBM\Trace Facility\;C:\Program Files (x86)\IBM\Mobility Client\;C:\Program Files (x86)\Skype\Phone\;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Intel\WirelessCommon\;.
??? 19, 2015 9:20:11 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-nio-8080"]
??? 19, 2015 9:20:11 PM org.apache.tomcat.util.net.NioSelectorPool getSharedSelector
INFO: Using a shared selector for servlet write/read
??? 19, 2015 9:20:11 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["ajp-nio-8009"]
??? 19, 2015 9:20:11 PM org.apache.tomcat.util.net.NioSelectorPool getSharedSelector
INFO: Using a shared selector for servlet write/read
??? 19, 2015 9:20:11 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 878 ms
??? 19, 2015 9:20:11 PM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Catalina
??? 19, 2015 9:20:11 PM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: Apache Tomcat/8.0.28
??? 19, 2015 9:20:15 PM org.apache.jasper.servlet.TldScanner scanJars
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
??? 19, 2015 9:20:15 PM org.apache.catalina.util.SessionIdGeneratorBase createSecureRandom
INFO: Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [228] milliseconds.
??? 19, 2015 9:20:22 PM org.apache.jasper.servlet.TldScanner scanJars
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
??? 19, 2015 9:20:23 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory C:\RPI automation\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\webapps\host-manager
??? 19, 2015 9:20:26 PM org.apache.jasper.servlet.TldScanner scanJars
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
??? 19, 2015 9:20:26 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deployment of web application directory C:\RPI automation\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\webapps\host-manager has finished in 3,151 ms
??? 19, 2015 9:20:26 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory C:\RPI automation\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\webapps\manager
??? 19, 2015 9:20:30 PM org.apache.jasper.servlet.TldScanner scanJars
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
??? 19, 2015 9:20:30 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deployment of web application directory C:\RPI automation\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\webapps\manager has finished in 3,157 ms
??? 19, 2015 9:20:30 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["http-nio-8080"]
??? 19, 2015 9:20:30 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["ajp-nio-8009"]
??? 19, 2015 9:20:30 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 18768 ms

这是我的 pom.xml：

<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.cybermesser.automation</groupId>
  <artifactId>automation</artifactId>
  <version>1.0</version>
  <packaging>war</packaging>
  <name>stack</name>
  <description>REST API</description>
  <build>
    <finalName>automation</finalName>
    <sourceDirectory>src</sourceDirectory>
    <plugins>    
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.3</version>
        <configuration>
          <source>1.7</source>
          <target>1.7</target>
        </configuration>
      </plugin>
      <plugin>
        <artifactId>maven-war-plugin</artifactId>
        <version>2.6</version>
        <configuration>
          <warSourceDirectory>WebContent</warSourceDirectory>
          <failOnMissingWebXml>false</failOnMissingWebXml>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.tomcat.maven</groupId>
        <artifactId>tomcat8-maven-plugin</artifactId>
        <version>2.1</version>
        <configuration>
          <url>http://yourhost:8080/manager/text</url>
        </configuration>
      </plugin>
    </plugins>
  </build>
    <dependencies>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-jdbc</artifactId>
            <version>8.0.28</version>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-servlet-api</artifactId>
            <version>8.0.28</version>
        </dependency>       
        <dependency>
            <groupId>org.ow2.asm</groupId>
            <artifactId>asm-all</artifactId>
            <version>5.0.4</version>
        </dependency>
        <dependency>
          <groupId>javax.servlet</groupId>
          <artifactId>javax.servlet-api</artifactId>
          <version>3.1.0</version>
          <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.glassfish.jersey.containers</groupId>
            <artifactId>jersey-container-servlet</artifactId>
            <version>2.22.1</version>
        </dependency>       
        <dependency>
          <groupId>org.glassfish.jersey.containers</groupId>
          <artifactId>jersey-container-servlet-core</artifactId>
          <version>2.22.1</version>
        </dependency>
        <dependency>        
            <groupId>org.glassfish.jersey.core</groupId>
            <artifactId>jersey-server</artifactId>
            <version>2.22.1</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>org.eclipse.persistence.jpa</artifactId>
            <version>2.6.1</version>
        </dependency>      
        <dependency>
            <groupId>org.json</groupId>
            <artifactId>json</artifactId>
            <version>20150729</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.37</version>
        </dependency>
    </dependencies>
</project>

这是我的 web.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
  <display-name>automation</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
 <display-name>stack</display-name>


   <servlet>
    <servlet-name>MyRESTService</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
     <!-- Register resources and providers under com.vogella.jersey.first package. -->
    <init-param>
        <param-name>jersey.config.server.provider.packages</param-name>
        <param-value>com.cybermesser.web.restful</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>MyRESTService</servlet-name>
    <url-pattern>/rest1/*</url-pattern>
  </servlet-mapping>


 <servlet>
    <servlet-name>Jersey REST Service</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
     <!-- Register resources and providers under com.vogella.jersey.first package. -->
    <init-param>
        <param-name>jersey.config.server.provider.packages</param-name>
        <param-value>com.vogella.jersey.first</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>Jersey REST Service</servlet-name>
    <url-pattern>/rest2/*</url-pattern>
  </servlet-mapping>
</web-app>

这是我的 JERSEY java 类：

package com.cybermesser.web.restful;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;

import javax.ws.rs.ApplicationPath;
import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import com.cybermesser.db.queries.DBQueries;

@Path("/hello")
public class RESTService {

      @GET
      @Produces(MediaType.TEXT_PLAIN)
      public String sayPlainTextHello() {
        return "Hello Jersey";
      }
}

这是我不在 web.xml 中的 java 应用程序示例：

package com.cybermesser.web.restful;


import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

import javax.ws.rs.ApplicationPath;
import javax.ws.rs.core.Application;

import com.cybermesser.web.restful.RESTService;

@ApplicationPath("/rest0")
public class RestApp extends Application {
  public Set<Class<?>> getClasses() {
    return new HashSet<Class<?>>(Arrays.asList(RESTService.class));
  }
}

我的 server.xml 的一部分：

     <Context docBase="AutomationWeb" path="/AutomationWeb" reloadable="true" source="org.eclipse.jst.jee.server:AutomationWeb"/></Host>
    </Engine>
  </Service>
</Server>

我的项目的 WebContent 文件夹中有 index.xml，它在本地主机：8080/AutomationWeb/index.html 我也有可用的 Tomcat 管理器应用程序 localhost:8080/manager/html 我可以在那里看到我的应用程序

我试过了本地主机：8080/AutomationWeb/rest0/hello 本地主机：8080/AutomationWeb/rest1/hello 本地主机：8080/AutomationWeb/rest2/hello

localhost:8080/rest0/hello 本地主机：8080/rest1/你好本地主机：8080/rest2/你好

localhost:8080/stack/rest1/hello

localhost:8080/AutomationWeb/stack/rest2/hello

以及其他一些变体，它们都返回 HTTP 404 代码

所以问题是：这是泽西的失败吗？如何诊断？我的服务的 URL 是什么样的？是否可以在服务器上显示所有可用的 URL？我是否缺少 pom.xml 中的依赖项？

我将非常感谢专家的帮助，为此奋斗了一整天......

【问题讨论】：

标签： java eclipse rest tomcat

【解决方案1】：

您在编写部署描述符时犯了错误。

<servlet-name>MyRESTService</servlet-name>
<servlet-name>Jersey REST Service</servlet-name>

更正第二个，即 Jersey Rest Service，应该可以工作

干杯！！

【讨论】：

您好，感谢您的回答，但实际上有 2 个 servlet 定义了相应的映射！所以这不是错误...

【解决方案2】：

我解决了这个问题。问题出在 Eclipse 中，而不是在我的代码中。自动构建或发布出错。

我在这里发布解决方案以帮助其他人：

停止 tomcat 服务器。
关闭自动构建。
刷新所有项目（项目右键->刷新）
执行干净构建
通过在项目上按右键以正确的顺序（如果一个依赖于另一个）手动构建每个项目 -> 构建
从 tomcat webapps 或 wtpwebapps 中删除应用程序的文件夹
eclipse中tomcat服务器上的右键->清理
eclipse中tomcat服务器上的右键->发布
确保您的 web-inf 中有 classes 文件夹和 web.xml，位于 Tomcat 的 wtpwebapps 或 webapps 的应用程序文件夹中，无论您设置了什么
启动服务器

我的代码是正确的。浪费了一天的时间。伙计们，Eclipse 太痛苦了……

更新：问题似乎是由进入循环的自动构建引起的。我通过在我的 maven web 项目的 .project 文件中注释掉以下代码并重新启动 eclipse 解决了这个问题（也许只是重新启动有帮助）

<!--
    <buildCommand>
        <name>org.eclipse.m2e.core.maven2Builder</name>
        <arguments>
        </arguments>
    </buildCommand> 
-->

现在自动构建和发布工作完美！

【讨论】：