java - org.apache.tomcat.SimpleInstanceManager 无法转换为 org.apache.tomcat.InstanceManager

Question

我试图将我的应用程序升级到 GWT 2.8 和 Java 8，但无论我遇到什么问题。请注意，我使用的是嵌入式 Jetty。

org.apache.jasper.JasperException: java.lang.ClassCastException: org.apache.tomcat.SimpleInstanceManager cannot be cast to org.apache.tomcat.InstanceManager
    at org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:585)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:396)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:405)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:349)
    at org.eclipse.jetty.jsp.JettyJspServlet.service(JettyJspServlet.java:107)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:812)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:587)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:577)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.handler.RequestLogHandler.handle(RequestLogHandler.java:95)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:499)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:544)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassCastException: org.apache.tomcat.SimpleInstanceManager cannot be cast to org.apache.tomcat.InstanceManager
    at org.apache.jasper.runtime.InstanceManagerFactory.getInstanceManager(InstanceManagerFactory.java:29)
    at org.apache.jsp.index_jsp._jspInit(index_jsp.java:32)
    at org.apache.jasper.runtime.HttpJspBase.init(HttpJspBase.java:49)
    at org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:180)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369)

很多依赖项来自 GWT 2.8，但这里是 pom.xml:

<build>
<sourceDirectory>src</sourceDirectory>
<testSourceDirectory>test</testSourceDirectory>
  <outputDirectory>war/WEB-INF/classes</outputDirectory>
<resources>
        <resource>
    <directory>src</directory>
    <excludes>
      <exclude>**/*.java</exclude>
    </excludes>
  </resource>
</resources>
<plugins>
  <plugin>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>2.3.2</version>
    <configuration>
        <source>1.8</source>
        <target>1.8</target>
    </configuration>
  </plugin>
</plugins>
 </build>
<dependencies>
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-compress</artifactId>
    <version>1.10</version>
</dependency>
<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.2.2</version>
</dependency>
<dependency>
    <groupId>org.vectomatic</groupId>
    <artifactId>lib-gwt-file</artifactId>
    <version>0.3.1</version>
</dependency>
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.1</version>
</dependency>
<dependency>
    <groupId>com.asimalp.commons</groupId>
    <artifactId>asimalp-commons</artifactId>
    <version>3.0.0</version>
</dependency>
<dependency>
    <groupId>com.asimalp.poi</groupId>
    <artifactId>asimalp-poi</artifactId>
    <version>1.0.0</version>
</dependency>
<dependency>
    <groupId>com.google.gwt</groupId>
    <artifactId>gwt-visualization</artifactId>
    <version>1.1.2</version>
</dependency>
<dependency>
    <groupId>org.postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <version>9.3-1101-jdbc41</version>
</dependency>
<dependency>
    <groupId>com.microsoft.sqlserver</groupId>
    <artifactId>sqljdbc4</artifactId>
    <version>4.0</version>
</dependency>
<dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava-gwt</artifactId>
    <version>20.0</version>
</dependency>
<dependency>
    <groupId>org.apache.axis</groupId>
    <artifactId>axis</artifactId>
    <version>1.4</version>
</dependency>
<dependency>
    <groupId>javax.xml</groupId>
    <artifactId>jaxrpc</artifactId>
    <version>1.1</version>
</dependency>
<dependency>
    <groupId>org.eclipse.birt.runtime.3_7_1</groupId>
    <artifactId>javax.wsdl</artifactId>
    <version>1.5.1</version>
</dependency>
<dependency>
    <groupId>dom4j</groupId>
    <artifactId>dom4j</artifactId>
    <version>1.6.1</version>
</dependency>
<dependency>
    <groupId>javax.comm</groupId>
    <artifactId>comm</artifactId>
    <version>2.0</version>
</dependency>
<dependency>
    <groupId>ojdbc7</groupId>
    <artifactId>ojdbc7</artifactId>
    <version>12.1.0.2</version>
</dependency>
<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.7</version>
</dependency>
  </dependencies>

如有任何帮助，我们将不胜感激。

Answer 1

我认为这是一个类加载问题。以下解决方法对我有用:在您的应用程序启动时强制加载这两个类。这样(我认为)它们在主类加载器上。我在我的应用程序启动时加载的 servlet 中运行它:

@Override
public void init() throws ServletException {
    loadClass("org.apache.tomcat.InstanceManager");
    loadClass("org.apache.tomcat.SimpleInstanceManager");
}

private void loadClass(String className) {
    try {
        Class.forName(className);
    } catch (ClassNotFoundException cex) {}
}