使用原型gwt-maven-plugin 2.5.0
创建了一个gwt maven项目。
GWT服务器端依赖于BoneCP
(A ServletContextListener
应该实例化连接池)。 BoneCP取决于slf4j-api
。
启动DevMode会抛出NoClassDefFoundError
,尽管slf4j-api被添加为maven依赖,就像BoneCP一样:
Starting Jetty on port 8888
[WARN] failed com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload@12271e{/,/home/user/workspace/project/target\moduleName-0.0.1-SNAPSHOT}
java.lang.NoClassDefFoundError: org/slf4j/LoggerFactory
at com.jolbox.bonecp.BoneCPConfig.<clinit>(BoneCPConfig.java:62)
at my.group.artifact.server.db.ConnectionPool.<init>(ConnectionPool.java:41)
at my.group.artifact.server.db.ConnectionPool.getInstance(ConnectionPool.java:23)
at my.group.artifact.server.MyServletContextListener.contextInitialized(MyServletContextListener.java:26)
检查maven添加的jar中是否存在org.slf4j.LoggerFactory
。通过maven(例如BoneCP)添加的其他依赖项被找到。
Pom.xml和web.xml如下。
<?xml version="1.0" encoding="UTF-8"?>
<project
xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<!-- POM file generated with GWT webAppCreator -->
<modelVersion>4.0.0</modelVersion>
<groupId>my.group/groupId>
<artifactId>artifact</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>ModuleName</name>
<properties>
<!-- Convenience property to set the GWT version -->
<gwtVersion>2.5.0</gwtVersion>
<!-- GWT needs at least java 1.5 -->
<maven.compiler.source>1.6</maven.compiler.source>
<maven.compiler.target>1.6</maven.compiler.target>
<webappDirectory>${project.build.directory}/${project.build.finalName}</webappDirectory>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
</properties>
<dependencies>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-servlet</artifactId>
<version>${gwtVersion}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-user</artifactId>
<version>${gwtVersion}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.7</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.0.0.GA</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.0.0.GA</version>
<classifier>sources</classifier>
<scope>test</scope>
</dependency>
<!-- mine -->
<dependency>
<groupId>com.google.inject</groupId>
<artifactId>guice</artifactId>
<version>3.0</version>
</dependency>
<dependency>
<groupId>com.google.gwt.inject</groupId>
<artifactId>gin</artifactId>
<version>2.1.2</version>
</dependency>
<dependency>
<groupId>com.jolbox</groupId>
<artifactId>bonecp</artifactId>
<version>0.8.0.RELEASE</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.27</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>15.0</version>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava-gwt</artifactId>
<version>15.0</version>
</dependency>
</dependencies>
<build>
<!-- Generate compiled stuff in the folder used for developing mode -->
<outputDirectory>${webappDirectory}/WEB-INF/classes</outputDirectory>
<plugins>
<!-- GWT Maven Plugin -->
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>gwt-maven-plugin</artifactId>
<version>2.5.0</version>
<executions>
<execution>
<goals>
<goal>compile</goal>
<!--<goal>test</goal>-->
<!--<goal>i18n</goal>-->
<goal>generateAsync</goal>
</goals>
</execution>
</executions>
<!-- Plugin configuration. There are many available options, see
gwt-maven-plugin documentation at codehaus.org -->
<configuration>
<runTarget>ModuleName.html</runTarget>
<hostedWebapp>${webappDirectory}</hostedWebapp>
<!--<i18nMessagesBundle>my.group.artifact.client.Messages</i18nMessagesBundle>-->
</configuration>
</plugin>
<!-- Copy static web files before executing gwt:run -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>2.1.1</version>
<executions>
<execution>
<phase>compile</phase>
<goals>
<goal>exploded</goal>
</goals>
</execution>
</executions>
<configuration>
<webappDirectory>${webappDirectory}</webappDirectory>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.3.2</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
相关的web.xml部分
<listener>
<listener-class>
my.group.artifact.server.MyServletContextListener
</listener-class>
</listener>
整个堆栈跟踪
[WARN] Server class 'com.mysql.jdbc.Driver' could not be found in the web app, but was found on the system classpath
[WARN] Adding classpath entry 'file:/C:/Documents%20and%20Settings/thomas/.m2/repository/mysql/mysql-connector-java/5.1.27/mysql-connector-java-5.1.27.jar' to the web app classpath for this session
For additional info see: file:/C:/Documents%20and%20Settings/thomas/Desktop/eclipse/plugins/com.google.gwt.eclipse.sdkbundle_2.5.1/gwt-2.5.1/doc/helpInfo/webAppClassPath.html
[WARN] Server class 'com.jolbox.bonecp.BoneCPConfig' could not be found in the web app, but was found on the system classpath
[WARN] Adding classpath entry 'file:/C:/Documents%20and%20Settings/thomas/.m2/repository/com/jolbox/bonecp/0.8.0.RELEASE/bonecp-0.8.0.RELEASE.jar' to the web app classpath for this session
For additional info see: file:/C:/Documents%20and%20Settings/thomas/Desktop/eclipse/plugins/com.google.gwt.eclipse.sdkbundle_2.5.1/gwt-2.5.1/doc/helpInfo/webAppClassPath.html
Starting Jetty on port 8888
[WARN] failed com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload@12271e{/,/home/user/workspace\project\target\moduleName-0.0.1-SNAPSHOT}
java.lang.NoClassDefFoundError: org/slf4j/LoggerFactory
at com.jolbox.bonecp.BoneCPConfig.<clinit>(BoneCPConfig.java:62)
at my.group.artifact.server.db.ConnectionPool.<init>(ConnectionPool.java:41)
at my.group.artifact.server.db.ConnectionPool.getInstance(ConnectionPool.java:23)
at my.group.artifact.server.MyServletContextListener.contextInitialized(MyServletContextListener.java:26)
at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:543)
at org.mortbay.jetty.servlet.Context.startContext(Context.java:136)
at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.Server.doStart(Server.java:222)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1093)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:836)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload$WebAppClassLoaderExtension.findClass(JettyLauncher.java:372)
at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:366)
at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:337)
... 22 more
[WARN] failed RequestLogHandler@19e9785
java.lang.NoClassDefFoundError: org/slf4j/LoggerFactory
at com.jolbox.bonecp.BoneCPConfig.<clinit>(BoneCPConfig.java:62)
at my.group.artifact.server.db.ConnectionPool.<init>(ConnectionPool.java:41)
at my.group.artifact.server.db.ConnectionPool.getInstance(ConnectionPool.java:23)
at my.group.artifact.server.MyServletContextListener.contextInitialized(MyServletContextListener.java:26)
at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:543)
at org.mortbay.jetty.servlet.Context.startContext(Context.java:136)
at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.Server.doStart(Server.java:222)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1093)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:836)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload$WebAppClassLoaderExtension.findClass(JettyLauncher.java:372)
at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:366)
at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:337)
... 22 more
[WARN] Error starting handlers
java.lang.NoClassDefFoundError: org/slf4j/LoggerFactory
at com.jolbox.bonecp.BoneCPConfig.<clinit>(BoneCPConfig.java:62)
at my.group.artifact.server.db.ConnectionPool.<init>(ConnectionPool.java:41)
at my.group.artifact.server.db.ConnectionPool.getInstance(ConnectionPool.java:23)
at my.group.artifact.server.MyServletContextListener.contextInitialized(MyServletContextListener.java:26)
at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:543)
at org.mortbay.jetty.servlet.Context.startContext(Context.java:136)
at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.Server.doStart(Server.java:222)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1093)
at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:836)
at com.google.gwt.dev.DevMode.main(DevMode.java:311)
Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload$WebAppClassLoaderExtension.findClass(JettyLauncher.java:372)
at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:366)
at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:337)
... 22 more
答案 0 :(得分:1)
[WARN] Server class 'com.mysql.jdbc.Driver' could not be found in the web app, but was found on the system classpath [WARN] Adding classpath entry 'file:/C:/Documents%20and%20Settings/thomas/.m2/repository/mysql/mysql-connector-java/5.1.27/mysql-connector-java-5.1.27.jar' to the web app classpath for this session For additional info see: file:/C:/Documents%20and%20Settings/thomas/Desktop/eclipse/plugins/com.google.gwt.eclipse.sdkbundle_2.5.1/gwt-2.5.1/doc/helpInfo/webAppClassPath.html [WARN] Server class 'com.jolbox.bonecp.BoneCPConfig' could not be found in the web app, but was found on the system classpath [WARN] Adding classpath entry 'file:/C:/Documents%20and%20Settings/thomas/.m2/repository/com/jolbox/bonecp/0.8.0.RELEASE/bonecp-0.8.0.RELEASE.jar' to the web app classpath for this session For additional info see: file:/C:/Documents%20and%20Settings/thomas/Desktop/eclipse/plugins/com.google.gwt.eclipse.sdkbundle_2.5.1/gwt-2.5.1/doc/helpInfo/webAppClassPath.html
这是线索。 JAR应该从WEB-INF/lib
加载,而不是从类路径加载。
这里有两点需要注意:
mvn package
一次(并且每次更改类路径/构建路径)都要将所有依赖项复制到WEB-INF/lib
中的target/
文件夹中DevMode找到它们所期望的位置。