将类移动到包后，Netbeans Java Web 应用程序不会部署

Question

我只是将我所有的 java 类移动到一个包 (SSP) 中，因为我将它们放在默认包 uo 中，现在我的应用程序不会再部署到 tomcat....

我用：

• Netbeans 8.0.2
• Tomcat 8.0.28
• PostgreSQL 9.4

我尝试了以下没有任何改变：

• 已删除 C:\Users\MyUser\AppData\Local\NetBeans\Cache 处的 Netbeans 缓存
• 清理并构建项目
• 关闭 tomcat 并重新启动它

错误（Tomcat 日志）：

03-Dec-2015 09:53:13.330 SEVERE [http-nio-8080-exec-4] org.apache.catalina.core.StandardContext.listenerStart Exception sending context initialized event to listener instance of class SSP.Startup  java.lang.NullPointerException
at SSP.Load_config.getPropValues_db_user_pw(Load_config.java:89)
at SSP.Roles_rights.get_roles_rights(Roles_rights.java:52)
at SSP.Roles_rights.getInstance(Roles_rights.java:35)
at SSP.Startup.contextInitialized(Startup.java:21)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4738)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5181)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:586)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:460)
at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1586)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300)
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
at org.apache.catalina.manager.ManagerServlet.check(ManagerServlet.java:1460)
at org.apache.catalina.manager.ManagerServlet.deploy(ManagerServlet.java:906)
at org.apache.catalina.manager.ManagerServlet.doGet(ManagerServlet.java:344)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:217)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:614)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

错误 Netbeans 调试：

FAIL - Deployed application at context path /Self-Service-Portal but context failed to start
D:\Dropbox\Bachelor\Java Projects\Self-Service-Portal\nbproject\build-impl.xml:1157: The module has not been deployed.

以下代码sn-ps是tomcat日志中命名的类：

SSP.Load_config.getPropValues_db_user_pw(Load_config.java:89)

72: public String getPropValues_db_user_pw() throws IOException {
73:    try {
74:        Properties prop = new Properties();
75:        String propFileName = "db_settings.properties";
76:        inputStream = getClass().getClassLoader().getResourceAsStream(propFileName);
77
78:        if (inputStream != null) {
79:            prop.load(inputStream);
80:        } else {
81:            throw new FileNotFoundException("property file '" + propFileName + "' not found in the classpath");
82:        }
83:        
84:        // compose result string (ip:port)
85:        result = prop.getProperty("db_passwd");
86:    } catch (Exception e) {
87:            System.out.println("Exception: " + e);
88:    } finally {
89:        if (inputStream != null) {
90:            inputStream.close();
91:        }
92:    }
93:    return result;
94: }

SSP.Roles_rights.get_roles_rights(Roles_rights.java:52)

40: public void get_roles_rights(){
41:
42:    // Get roles & rigths from db
43:    // variables
44:    JDBCConnection database_connection = null;
45:    ResultSet m_ResultSet = null;
46:
47:    // load standard db-user from config file
48:    Load_config properties = new Load_config();
49:
50:    // connect to postgreSQL Database
51:    try {
52:        database_connection = new JDBCConnection("Self-Service-Portal", properties.getPropValues_db_user(), properties.getPropValues_db_user_pw());
53:    } catch (IOException ex) {
54:        Logger.getLogger(User_management.class.getName()).log(Level.SEVERE, null, ex);
55:    }
       .......
114: } 

SSP.Roles_rights.getInstance(Roles_rights.java:35)

24:  public class Roles_rights {
25:     
26:     public List<List<Integer>> oe_fac_roles_rights = new ArrayList<List<Integer>>(4);
27: 
28:     private static Roles_rights instance = null;
29:     private Roles_rights() {
30:       // Exists only to defeat instantiation.
31:     }
32:     public static Roles_rights getInstance() {
33:         if(instance == null) {
34:             instance = new Roles_rights();
35:             instance.get_roles_rights();
36:         }
37:         return instance;
38:     }
39:    
40:     public void get_roles_rights(){ 
        ......
114:    }
115: }

SSP.Startup.contextInitialized(Startup.java:21)

16: public class Startup implements javax.servlet.ServletContextListener {
17:    
18:    @Override
19:    public void contextInitialized(ServletContextEvent sce) {
20:        // create singleton object to get all roles/rights from db
21:        Roles_rights tmp = Roles_rights.getInstance();
22:    }
23:
24:    @Override
25:    public void contextDestroyed(ServletContextEvent sce) {
26:        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
27:    }
28: }

以防万一我提供更多信息：

web.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="Self-Service-Portal" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee">
<servlet>
    <servlet-name>Login</servlet-name>
    <servlet-class>SSP.Login</servlet-class>
</servlet>
<servlet>
    <servlet-name>Usermode</servlet-name>
    <servlet-class>SSP.Usermode</servlet-class>
</servlet>
<servlet>
    <servlet-name>Echo_usermode</servlet-name>
    <servlet-class>SSP.Echo_usermode</servlet-class>
</servlet>
<servlet>
    <servlet-name>User_management</servlet-name>
    <servlet-class>SSP.User_management</servlet-class>
</servlet>

<servlet-mapping>
    <servlet-name>Login</servlet-name>
    <url-pattern>/portal.html</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>Usermode</servlet-name>
    <url-pattern>/usermode/*</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>Echo_usermode</servlet-name>
    <url-pattern>/echo_usermode</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>User_management</servlet-name>
    <url-pattern>/user_management/*</url-pattern>
</servlet-mapping>

<welcome-file-list>
    <welcome-file>index.html</welcome-file>
</welcome-file-list>

<listener>
    <listener-class>SSP.Startup</listener-class>
</listener>

我的项目结构

此外，Netbeans 向我显示 web.xml 的错误：

cvc-elt.1: Cannot find the declaration of element 'web-app'

因为这之前确实显示过并且从未引起问题我不知道这是否可能是原因

是否有人知道为什么我的应用程序不会部署只是因为我的类现在在包 SSP 中，而不是在默认包中，因为我调整了 web.xml 中的包更改？？

问候 阿尔卡纳

Answer 1

您尝试关闭您的输入流，即使它为空。考虑改为尝试使用资源。或者至少在关闭它之前检查 inputStream 是否为!= null。

73:    try {
76:        inputStream = getClass().getResourceAsStream(propFileName);
77
78:        if (inputStream != null) {
80:        } else {
82:        }
83:        
88:    } finally {
89:            inputStream.close(); //Might be null -> cause of your error
90:    }

至于为空的原因：检查属性文件是否部署到您认为应该放置的位置。尝试使用getClass().getResourceAsStream() 而不是使用类加载器方法。尝试使用绝对路径/SSP/db_settings.properties。