Java开发网 - 你好：请问为什么JAVA程序不能编译？

Topic: 你好：请问为什么JAVA程序不能编译？

1.你好：请问为什么JAVA程序不能编译？

Posted by: guopu1
Posted on: 2005-03-28 15:09

你好：
请问为什么JAVA程序不能编译？
我在win2000 C：上安装的是jswdk-1.0和j2sdk1.4.2_07环境变量设为：
CLASSPATH=c:\j2sdk1.4.2_07\lib\tools.jar;c:\j2sdk1.4.2_07\jre\lib\rt.jar;
PATH=%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;c:\j2sdk1.4.2_07\bin
源程序是jswdk-1.0里的现成JAVA文件：
/* $Id: SnoopServlet.java,v 1.1 1999/03/17 01:17:20 duncan Exp $
*
*/

import java.io.IOException;
import java.util.Enumeration;
import javax.servlet.*;
import javax.servlet.http.*;

/**
*
*
* @author James Duncan Davidson <duncan@eng.sun.com>
*/

public class SnoopServlet extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
  ServletConfig config = getServletConfig();
ServletOutputStream out = response.getOutputStream();
out.println("Snoop Servlet");
  out.println();
  out.println("Init Parameters");
  Enumeration e = config.getInitParameterNames();
  while (e.hasMoreElements()) {
   String key = (String)e.nextElement();
   String value = config.getInitParameter(key);
   out.println(" " + key + " = " + value);
  }
  out.println();
  out.println("Context attributes:");
  ServletContext context = config.getServletContext();
  Enumeration enum = context.getAttributeNames();
  while (enum.hasMoreElements()) {
   String key = (String)enum.nextElement();
Object value = context.getAttribute(key);
out.println(" " + key + " = " + value);
  }
  out.println();

  out.println("javax.servlet.Servlet methods");
out.println();
out.println("Attribute names in this request:");
e = request.getAttributeNames();
while (e.hasMoreElements()) {
String key = (String)e.nextElement();
Object value = request.getAttribute(key);
out.println(" " + key + " = " + value);
}
out.println();
out.println("Protocol: " + request.getProtocol());
out.println("Scheme: " + request.getScheme());
out.println("Server Name: " + request.getServerName());
out.println("Server Port: " + request.getServerPort());
out.println("Server Info: " +

getServletConfig().getServletContext().getServerInfo());
out.println("Remote Addr: " + request.getRemoteAddr());
out.println("Remote Host: " + request.getRemoteHost());
out.println("Character Encoding: " + request.getCharacterEncoding());
out.println("Content Length: " + request.getContentLength());
out.println("Content Type: "+ request.getContentType());
out.println();
out.println("Parameter names in this request");
e = request.getParameterNames();
while (e.hasMoreElements()) {
String key = (String)e.nextElement();
String[] values = request.getParameterValues(key);
out.print(" " + key + " = ");
for(int i = 0; i < values.length; i++) {
out.print(values[i] + " ");
}
out.println();
}
out.println();
out.println("javax.servlet.http.HttpServletRequest methods");
out.println();
out.println("Headers in this request");
e = request.getHeaderNames();
while (e.hasMoreElements()) {
String key = (String)e.nextElement();
String value = request.getHeader(key);
out.println(" " + key + " : " + value);
}
out.println();
out.println("Cookies in this request");
Cookie[] cookies = request.getCookies();
for (int i = 0; i < cookies.length; i++) {
Cookie cookie = cookies[i];
out.println(" " + cookie.getName() + " = " + cookie.getValue());
}
out.println();

out.println("Auth Type: " + request.getAuthType());
out.println("HTTP Method: " + request.getMethod());
out.println("Path Info: " + request.getPathInfo());
  out.println("Path Trans: " + request.getPathTranslated());
out.println("Query String: " + request.getQueryString());
out.println("Remote User: " + request.getRemoteUser());
out.println("Session Id: " + request.getRequestedSessionId());
out.println("Request URI: " + request.getRequestURI());
out.println("Servlet Path: " + request.getServletPath());

out.println();
out.println("Session Information");
HttpSession session = request.getSession(true);
  out.println("Created: " + session.getCreationTime());
out.println("ID: " + session.getId());
out.println("Last Accessed: " + session.getLastAccessedTime());
out.println("Max Inactive Interval: " +
session.getMaxInactiveInterval());
out.println();
out.println("Values: ");
String[] valueNames = session.getValueNames();
for (int i = 0; i < valueNames.length; i++) {
out.println(" " + valueNames[i] + " = " +
session.getValue(valueNames[i]));
}
out.println();
}
}

编译时出错提示为：
C:\>javac et.java
et.java:16: class SnoopServlet is public, should be declared in a file named Sno
opServlet.java
public class SnoopServlet extends HttpServlet {
^
et.java:7: package javax.servlet does not exist
import javax.servlet.*;
^
et.java:8: package javax.servlet.http does not exist
import javax.servlet.http.*;
^
et.java:16: cannot resolve symbol
symbol : class HttpServlet
location: class SnoopServlet
public class SnoopServlet extends HttpServlet {
^
et.java:18: cannot resolve symbol
symbol : class HttpServletRequest
location: class SnoopServlet
public void doGet(HttpServletRequest request, HttpServletResponse response)
^
et.java:18: cannot resolve symbol
symbol : class HttpServletResponse
location: class SnoopServlet
public void doGet(HttpServletRequest request, HttpServletResponse response)
^
et.java:19: cannot resolve symbol
symbol : class ServletException
location: class SnoopServlet
throws ServletException, IOException
^
et.java:21: cannot resolve symbol
symbol : class ServletConfig
location: class SnoopServlet
ServletConfig config = getServletConfig();
^
et.java:21: cannot resolve symbol
symbol : method getServletConfig ()
location: class SnoopServlet
ServletConfig config = getServletConfig();
^
et.java:22: cannot resolve symbol
symbol : class ServletOutputStream
location: class SnoopServlet
ServletOutputStream out = response.getOutputStream();
^
et.java:34: cannot resolve symbol
symbol : class ServletContext
location: class SnoopServlet
ServletContext context = config.getServletContext();
^
et.java:57: cannot resolve symbol
symbol : method getServletConfig ()
location: class SnoopServlet
out.println("Server Info: " + getServletConfig().getServletContext().get
ServerInfo());
^
et.java:87: cannot resolve symbol
symbol : class Cookie
location: class SnoopServlet
Cookie[] cookies = request.getCookies();
^
et.java:89: cannot resolve symbol
symbol : class Cookie
location: class SnoopServlet
Cookie cookie = cookies[i];
^
et.java:106: cannot resolve symbol
symbol : class HttpSession
location: class SnoopServlet
HttpSession session = request.getSession(true);
^
15 errors

2.Re:你好：请问为什么JAVA程序不能编译？ [Re: guopu1]	Copy to clipboard
Posted by: zhaojs Posted on: 2005-03-28 16:06 你的代码是要实现servlet吧?

3.Re:你好：请问为什么JAVA程序不能编译？ [Re: guopu1]	Copy to clipboard
Posted by: qingbo777 Posted on: 2005-03-28 16:31 简直有太多问题. 首先: 编译时出错提示为： C:\>javac et.java 很明显,你的文件名起成了et.java.可是你的public class 名是SnoopServlet.两者要一致. 再者: 你的CLASSPATH变量没有加入"."路径,就是当前目录. 并且你没有把servlet-api.jar(tomcat下)的包加进去啊.

4.Re:你好：请问为什么JAVA程序不能编译？ [Re: guopu1]

Copy to clipboard

Posted by: why
Posted on: 2005-03-28 20:12

this duplicated topic was deleted:
http://www.cjsdn.net/post/view?bid=1&id=139067

I wrote on 2005-03-27:
you need to add to the classpath the servlet.jar of your web container, jwsdk.
better use something newer and better like Tomcat or Resin.

and guopu1 replied:

Thank you for answering my question! I add the servlet.jar of your web container, jwsdk to the classpath ,but I still can not javac the java file.

Try something simpler (well, smaller, shorter) first!