在Oracle中使用Jetty的连接池

Question

我正在尝试使用ConnectionPooling服务器在Oracle中实现Jetty的概念。我试过在教程中看到的以下内容。如果我使用Tomcat服务器进行部署，它是可以工作的，但是Jetty似乎给了我一个不同寻常的error。详情如下-

我有一个名为TestServlet.java的类，定义为-

import java.io.IOException;
import java.sql.*;
import javax.naming.*;
import javax.servlet.*;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import javax.sql.DataSource;


@SuppressWarnings("serial")
@WebServlet("/TestServlet")
public class TestServlet extends HttpServlet {
public TestServlet() throws ServletException{
    System.out.println("Constructor");
    init();
}
public DataSource dataSource;
private Connection con;
private Statement statement;

public void init() throws ServletException {
    System.out.println("inside init method");
    try {
        // Get DataSource
        Context initContext  = new InitialContext();
        System.out.println("Before envcontext");
        Context envContext  = (Context)initContext.lookup("java:comp/env");
        System.out.println("After envcontext");
        dataSource = (DataSource)envContext.lookup("jdbc/DSTest");
        System.out.println(dataSource.toString());
    } catch (NamingException e) {
        System.out.println("Exception in try");
        e.printStackTrace();
    }
}

public void doGet(HttpServletRequest req, HttpServletResponse resp)
        throws ServletException, IOException {
    System.out.println("Request: "+req+"\tResponse: "+resp);
     int i=0;
    ResultSet resultSet = null;
    try {
        // Get Connection and Statement
        con = dataSource.getConnection();
        statement = con.createStatement();
        String query = "SELECT * FROM USER";
        resultSet = statement.executeQuery(query);
        while (resultSet.next()) {
            ++i;
            System.out.println(i+":\nID:"+resultSet.getString("ID") +"\nEmail:"+ resultSet.getString("UEMAIL") +"\nPassword:" + resultSet.getString("PASSWORD")+"\nFlag:"+resultSet.getShort("FLAG")
                    +"\n");

        }
    } catch (SQLException e) {
        System.out.println("EXCEPTIOn");
        e.printStackTrace();
    }finally {
        try { if(null!=resultSet)resultSet.close();} catch (SQLException e) 
        {e.printStackTrace();System.out.println("1");}
        try { if(null!=statement)statement.close();} catch (SQLException e) 
        {e.printStackTrace();System.out.println("2");}
        try { if(null!=con)con.close();} catch (SQLException e) 
        {e.printStackTrace();System.out.println("3");}
    }
}

}

我的Jetty-web.xml是-

<?xml version="1.0" encoding="UTF-8"?>
<Configure class="org.eclipse.jetty.webapp.WebAppContext">
<New id="DSTest" class="org.eclipse.jetty.plus.jndi.Resource">
 <Arg>java:comp/env</Arg>
 <Arg>jdbc/DSTest</Arg>
 <Arg>
     <New class="org.apache.commons.dbcp.BasicDataSource">
        <Set name="driverClassName">oracle.jdbc.OracleDriver</Set>
        <Set  name="url">ConnectionUrl</Set>
        <Set name="username">app_user</Set>
        <Set name="password">abcd</Set>
     </New>
 </Arg>
</New>
</Configure>

当我运行servlet类时，会发现一个错误，即-

java.lang.NoClassDefFoundError: org/apache/commons/pool/impl/GenericObjectPool
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2658)
at java.lang.Class.getConstructors(Class.java:1638)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:748)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.itemValue(XmlConfiguration.java:1078)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.value(XmlConfiguration.java:993)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:741)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:383)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:317)
at org.eclipse.jetty.xml.XmlConfiguration.configure(XmlConfiguration.java:276)
at org.eclipse.jetty.webapp.JettyWebXmlConfiguration.configure(JettyWebXmlConfiguration.java:100)
at org.eclipse.jetty.webapp.WebAppContext.configure(WebAppContext.java:427)
at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1207)
at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:610)
at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:453)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:89)
at org.eclipse.jetty.server.Server.doStart(Server.java:262)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at runjettyrun.Bootstrap.main(Bootstrap.java:80)
Caused by: 
java.lang.ClassNotFoundException: org.apache.commons.pool.impl.GenericObjectPool
at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
at org.eclipse.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:415)
at runjettyrun.ProjectClassLoader.loadClass(ProjectClassLoader.java:92)
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2658)
at java.lang.Class.getConstructors(Class.java:1638)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:748)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.itemValue(XmlConfiguration.java:1078)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.value(XmlConfiguration.java:993)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:741)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:383)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:317)
at org.eclipse.jetty.xml.XmlConfiguration.configure(XmlConfiguration.java:276)
at org.eclipse.jetty.webapp.JettyWebXmlConfiguration.configure(JettyWebXmlConfiguration.java:100)
at org.eclipse.jetty.webapp.WebAppContext.configure(WebAppContext.java:427)
at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1207)
at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:610)
at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:453)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:89)
at org.eclipse.jetty.server.Server.doStart(Server.java:262)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at runjettyrun.Bootstrap.main(Bootstrap.java:80)
2015-10-30 14:22:51.172:INFO:oejs.AbstractConnector:Started     SelectChannelConnector@0.0.0.0:8081 STARTING
2015-10-30 14:22:51.172:WARN:oejuc.AbstractLifeCycle:FAILED   org.eclipse.jetty.server.Server@7857fe2: java.lang.NoClassDefFoundError:   org/apache/commons/pool/impl/GenericObjectPool
java.lang.NoClassDefFoundError: org/apache/commons/pool/impl/GenericObjectPool
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2658)
at java.lang.Class.getConstructors(Class.java:1638)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:748)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.itemValue(XmlConfiguration.java:1078)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.value(XmlConfiguration.java:993)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:741)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:383)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:317)
at org.eclipse.jetty.xml.XmlConfiguration.configure(XmlConfiguration.java:276)
at org.eclipse.jetty.webapp.JettyWebXmlConfiguration.configure(JettyWebXmlConfiguration.java:100)
at org.eclipse.jetty.webapp.WebAppContext.configure(WebAppContext.java:427)
at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1207)
at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:610)
at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:453)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:89)
at org.eclipse.jetty.server.Server.doStart(Server.java:262)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at runjettyrun.Bootstrap.main(Bootstrap.java:80)
Caused by: 
java.lang.ClassNotFoundException: org.apache.commons.pool.impl.GenericObjectPool
at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
at org.eclipse.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:415)
at runjettyrun.ProjectClassLoader.loadClass(ProjectClassLoader.java:92)
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2658)
at java.lang.Class.getConstructors(Class.java:1638)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:748)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.itemValue(XmlConfiguration.java:1078)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.value(XmlConfiguration.java:993)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:741)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:383)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:317)
at org.eclipse.jetty.xml.XmlConfiguration.configure(XmlConfiguration.java:276)
at org.eclipse.jetty.webapp.JettyWebXmlConfiguration.configure(JettyWebXmlConfiguration.java:100)
at org.eclipse.jetty.webapp.WebAppContext.configure(WebAppContext.java:427)
at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1207)
at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:610)
at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:453)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:89)
at org.eclipse.jetty.server.Server.doStart(Server.java:262)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at runjettyrun.Bootstrap.main(Bootstrap.java:80)
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/pool/impl/GenericObjectPool
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2658)
at java.lang.Class.getConstructors(Class.java:1638)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:748)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.itemValue(XmlConfiguration.java:1078)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.value(XmlConfiguration.java:993)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.newObj(XmlConfiguration.java:741)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:383)
at org.eclipse.jetty.xml.XmlConfiguration$JettyXmlConfiguration.configure(XmlConfiguration.java:317)
at org.eclipse.jetty.xml.XmlConfiguration.configure(XmlConfiguration.java:276)
at org.eclipse.jetty.webapp.JettyWebXmlConfiguration.configure(JettyWebXmlConfiguration.java:100)
at org.eclipse.jetty.webapp.WebAppContext.configure(WebAppContext.java:427)
at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1207)
at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:610)
at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:453)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:89)
at org.eclipse.jetty.server.Server.doStart(Server.java:262)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:59)
at runjettyrun.Bootstrap.main(Bootstrap.java:80)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.pool.impl.GenericObjectPool
at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
at org.eclipse.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:415)
at runjettyrun.ProjectClassLoader.loadClass(ProjectClassLoader.java:92)
... 20 more

在查看其他堆栈溢出线程之后，我在eclipse中将commons-dbcp-1.4.jar添加到了WEB-INF/lib文件夹中。即使在这样做之后，我在Jetty上部署时也会遇到同样的错误。

我使用的是与jetty 4.4.1集成的eclipse luna服务器版本8。

任何帮助都很感激。

Answer 1

你有三种方法可以做到：

1. 如果在项目中使用maven或gradle，只需在pom.xml或build.gradle文件中添加公用池依赖项(推荐方法)。
2. 如果您没有使用上述工具之一，请将正确的jar放在WEB/lib目录中。
3. 最后一个是将jar放在${jettyHome}/lib目录中

确保您正在为当前的commons实现使用正确版本的公域池。

Answer 2

你不，你只是用猫来代替。http://tomcat.apache.org/ :) 注意到，只有当您需要使本地应用程序开发更容易时，才能很好地使用jetty。https://tomcat.apache.org/tomcat-7.0-doc/jdbc-pool.html我建议您开始阅读tomcat的基础知识，当您开始了解事情是如何工作的时，您应该开始实现Connection Pooling :)希望这会有所帮助。

Answer 3

对于Jetty10.x，您可以通过以下方式解析它，

1. 启用ext module -> java -jar start.jar --add-modules=ext
2. 在$JETTY_BASE/start.d/ext.ini中，将在执行1之后创建)
3. 将oralce jdbc文件放置在$JETTY_HOME/lib/ext/位置
4. 再次启动应用程序-> java -jar start.jar