我是服务器开发的新手，是从 Lars Vogel 的简单教程开始的。 使用 Eclipse WTP 进行 Servlet 和 JSP 开发。
一步一步地按照本教程：
- 安装了 Eclipse Java EE Kepler；
- 在 Ubuntu 12.04 上安装了 tomcat 7 -
http://localhost:8080/显示正确的 tomcat 页面； - 在eclipse中设置tomcat运行环境；
- 将tomcat服务器添加到eclipse；
- 创建
DAO； - 创建了 Servlet；
- 运行 =>
在这里我抓住了下一个提示：
Sep 15, 2013 3:40:39 PM org.apache.catalina.core.AprLifecycleListener init
INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: /usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
Sep 15, 2013 3:40:42 PM org.apache.tomcat.util.digester.SetPropertiesRule begin
WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:com.filecounter' did not find a matching property.
Sep 15, 2013 3:40:43 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-bio-8080"]
Sep 15, 2013 3:40:43 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["ajp-bio-8009"]
Sep 15, 2013 3:40:43 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 5203 ms
Sep 15, 2013 3:40:43 PM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Catalina
Sep 15, 2013 3:40:43 PM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: Apache Tomcat/7.0.42
Sep 15, 2013 3:40:45 PM org.apache.catalina.util.SessionIdGenerator createSecureRandom
INFO: Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [171] milliseconds.
Sep 15, 2013 3:40:46 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["http-bio-8080"]
Sep 15, 2013 3:40:46 PM org.apache.coyote.AbstractProtocol start
INFO: Starting ProtocolHandler ["ajp-bio-8009"]
Sep 15, 2013 3:40:46 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 2882 ms
这是tomcat/lib文件夹的内容：
nazar_art@nazar-desctop:/usr/local/tomcat/apache-tomcat-7.0.42/lib$ ls -lg
total 6132
-rwxrwxrwx 1 nazar_art 15264 Jul 2 10:59 annotations-api.jar
-rwxrwxrwx 1 nazar_art 54142 Jul 2 10:59 catalina-ant.jar
-rwxrwxrwx 1 nazar_art 134215 Jul 2 10:59 catalina-ha.jar
-rwxrwxrwx 1 nazar_art 1581311 Jul 2 10:59 catalina.jar
-rwxrwxrwx 1 nazar_art 257520 Jul 2 10:59 catalina-tribes.jar
-rwxrwxrwx 1 nazar_art 1801636 Jul 2 10:59 ecj-4.2.2.jar
-rwxrwxrwx 1 nazar_art 46085 Jul 2 10:59 el-api.jar
-rwxrwxrwx 1 nazar_art 123241 Jul 2 10:59 jasper-el.jar
-rwxrwxrwx 1 nazar_art 599428 Jul 2 10:59 jasper.jar
-rwxrwxrwx 1 nazar_art 88690 Jul 2 10:59 jsp-api.jar
-rwxrwxrwx 1 nazar_art 177598 Jul 2 10:59 servlet-api.jar
-rwxrwxrwx 1 nazar_art 6873 Jul 2 10:59 tomcat-api.jar
-rwxrwxrwx 1 nazar_art 796527 Jul 2 10:59 tomcat-coyote.jar
-rwxrwxrwx 1 nazar_art 235411 Jul 2 10:59 tomcat-dbcp.jar
-rwxrwxrwx 1 nazar_art 77364 Jul 2 10:59 tomcat-i18n-es.jar
-rwxrwxrwx 1 nazar_art 48693 Jul 2 10:59 tomcat-i18n-fr.jar
-rwxrwxrwx 1 nazar_art 51678 Jul 2 10:59 tomcat-i18n-ja.jar
-rwxrwxrwx 1 nazar_art 124006 Jul 2 10:59 tomcat-jdbc.jar
-rwxrwxrwx 1 nazar_art 23201 Jul 2 10:59 tomcat-util.jar
这是 catalina.2013-09-15.log 的内容。
更新：
这是教程：
在 Linux Ubuntu 12.04 上安装 Apache Tomcat Native
更新2：
这是数据访问对象的内容：
public class FileDao {
public int getCount() {
int count = 0;
// Load the file with the counter
FileReader fileReader = null;
BufferedReader bufferedReader = null;
PrintWriter writer = null ;
try {
File f = new File("FileCounter.initial");
if (!f.exists()) {
f.createNewFile();
writer = new PrintWriter(new FileWriter(f));
writer.println(0);
}
if (writer !=null){
writer.close();
}
fileReader = new FileReader(f);
bufferedReader = new BufferedReader(fileReader);
String initial = bufferedReader.readLine();
count = Integer.parseInt(initial);
} catch (Exception ex) {
if (writer !=null){
writer.close();
}
}
if (bufferedReader != null) {
try {
bufferedReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return count;
}
public void save(int count) throws Exception {
FileWriter fileWriter = null;
PrintWriter printWriter = null;
fileWriter = new FileWriter("FileCounter.initial");
printWriter = new PrintWriter(fileWriter);
printWriter.println(count);
// Make sure to close the file
if (printWriter != null) {
printWriter.close();
}
}
}
这里是 Servlet 代码：
public class FileCounter extends HttpServlet {
private static final long serialVersionUID = 1L;
int count;
private FileDao dao;
public void init() throws ServletException {
dao = new FileDao();
try {
count = dao.getCount();
} catch (Exception e) {
getServletContext().log("An exception occurred in FileCounter", e);
throw new ServletException("An exception occurred in FileCounter"
+ e.getMessage());
}
}
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// Set a cookie for the user, so that the counter does not increate
// every time the user press refresh
HttpSession session = request.getSession(true);
// Set the session valid for 5 secs
session.setMaxInactiveInterval(5);
response.setContentType("text/plain");
PrintWriter out = response.getWriter();
if (session.isNew()) {
count++;
}
out.println("This site has been accessed " + count + " times.");
}
public void destroy() {
super.destroy();
try {
dao.save(count);
} catch (Exception e) {
e.printStackTrace();
}
}
}
我还web.xml没有。
如何解决这个麻烦？