Java将无法使用RequestDispatcher进行编译，并且正确设置了类路径 [英] java won't compile with RequestDispatcher, classpath set correctly
问题描述
我正在使用ubuntu，并且一直根据我的研究和之前有关编译问题的帖子尝试进行编译。这次我怀疑是CLASSPATH，但无法弄清楚到底是什么问题。
I'm using ubuntu and I've been trying to compile based on my research and my previous posting regarding to compilation issue. This time I suspect CLASSPATH but cannot figure out what is wrong really.
（我要包含的Java文件）
(The java file I want to complie)
/home/makun/tomcat/apache-tomcat-6.0.26/webapps/head_first
/src/com/masatosan/registerservlet/RegisterServlet.java
这是Servlet类，它使用RequestDispatcher类扩展了HttpServlet。
This is the servlet class that extends HttpServlet thus using RequestDispatcher class.
我在Tomcat的目录中有servlet-api.jar：
I have servlet-api.jar in tomcat directory:
/home/makun/tomcat/apache-tomcat-6.0.26/lib/servlet -api.jar
所以我将路径添加到CLASSPATH，然后我的CLASSPATH看起来像：
So I added the path to CLASSPATH then my CLASSPATH looks like:
CLASSPATH = / usr / bin;。; / home / makun / tomcat / apache-tomcat-6.0.26 / webapps / head_first / src; / usr / share / java / lib; / home / makun / Desktop / java_run; /主页/makun/tomcat/apache-tomcat-6.0.26/webapps/head_first/src;/usr/share/java/lib;/home/makun/tomcat/apache-tomcat-6.0.26/lib;/主页/makun/tomcat/apache-tomcat-6.0.26/lib/servlet-api.jar
CLASSPATH=/usr/bin;.;/home/makun/tomcat/apache-tomcat-6.0.26/webapps/head_first/src;/usr/share/java/lib;/home/makun/Desktop/java_run;/home/makun/tomcat/apache-tomcat-6.0.26/webapps/head_first/src;/usr/share/java/lib;/home/makun/tomcat/apache-tomcat-6.0.26/lib;/home/makun/tomcat/apache-tomcat-6.0.26/lib/servlet-api.jar
现在我尝试我当前目录中的mplie RegisterServlet.java是 /home/makun/tomcat/apache-tomcat-6.0.26/webapps/head_first
/ src / com / masatosan / registerservlet
Now I try to complie RegisterServlet.java from my current directory which is /home/makun/tomcat/apache-tomcat-6.0.26/webapps/head_first /src/com/masatosan/registerservlet
javac -verbose -cp。：/ home / makun / tomcat / apache-tomcat-6.0.26 / lib ./RegisterServlet.java
然后出现邪恶错误...
Then evil errors show up...
makun /home/makun/tomcat/apache-tomcat-6.0.26/webapps/head_first/src/com/masatosan/registerservlet ->javac -verbose -cp .:/home/makun/tomcat/apache-tomcat-6.0.26/lib ./RegisterServlet.java
[parsing started ./RegisterServlet.java]
[parsing completed 81ms]
[search path for source files: .,/home/makun/tomcat/apache-tomcat-6.0.26/lib]
[search path for class files: /usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/resources.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/rt.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/sunrsasign.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/jsse.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/jce.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/charsets.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/classes,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/ext/sunpkcs11.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/ext/sunjce_provider.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/ext/localedata.jar,/usr/lib/jvm/java-6-sun-1.6.0.20/jre/lib/ext/dnsns.jar,.,/home/makun/tomcat/apache-tomcat-6.0.26/lib]
[loading java/io/IOException.class(java/io:IOException.class)]
[loading java/util/ArrayList.class(java/util:ArrayList.class)]
[loading java/util/HashMap.class(java/util:HashMap.class)]
[loading java/util/List.class(java/util:List.class)]
[loading java/util/Map.class(java/util:Map.class)]
./RegisterServlet.java:9: package javax.servlet does not exist
import javax.servlet.RequestDispatcher;
^
./RegisterServlet.java:10: package javax.servlet does not exist
import javax.servlet.ServletException;
^
./RegisterServlet.java:11: package javax.servlet.http does not exist
import javax.servlet.http.HttpServlet;
^
./RegisterServlet.java:12: package javax.servlet.http does not exist
import javax.servlet.http.HttpServletRequest;
^
./RegisterServlet.java:13: package javax.servlet.http does not exist
import javax.servlet.http.HttpServletResponse;
^
./RegisterServlet.java:16: cannot find symbol
symbol: class HttpServlet
public class RegisterServlet extends HttpServlet {
^
[loading java/lang/String.class(java/lang:String.class)]
./RegisterServlet.java:24: cannot find symbol
symbol : class HttpServletRequest
location: class com.masatosan.registerservlet.RegisterServlet
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
^
./RegisterServlet.java:24: cannot find symbol
symbol : class HttpServletResponse
location: class com.masatosan.registerservlet.RegisterServlet
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
^
./RegisterServlet.java:24: cannot find symbol
symbol : class ServletException
location: class com.masatosan.registerservlet.RegisterServlet
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
^
./RegisterServlet.java:28: cannot find symbol
symbol : class HttpServletRequest
location: class com.masatosan.registerservlet.RegisterServlet
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
^
./RegisterServlet.java:28: cannot find symbol
symbol : class HttpServletResponse
location: class com.masatosan.registerservlet.RegisterServlet
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
^
./RegisterServlet.java:28: cannot find symbol
symbol : class ServletException
location: class com.masatosan.registerservlet.RegisterServlet
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
^
[checking com.masatosan.registerservlet.RegisterServlet]
[loading java/util/AbstractMap.class(java/util:AbstractMap.class)]
[loading java/lang/Object.class(java/lang:Object.class)]
[loading java/lang/Exception.class(java/lang:Exception.class)]
[loading java/lang/Throwable.class(java/lang:Throwable.class)]
./RegisterServlet.java:55: cannot find symbol
symbol : class RequestDispatcher
location: class com.masatosan.registerservlet.RegisterServlet
RequestDispatcher dispatcher = request.getRequestDispatcher(address);
^
[loading java/lang/CharSequence.class(java/lang:CharSequence.class)]
[loading java/io/Serializable.class(java/io:Serializable.class)]
[loading java/lang/Comparable.class(java/lang:Comparable.class)]
[total 828ms]
13 errors
有人可以帮我指出为什么我的编译器找不到RequestDispatcher吗？
Can anyone help me point out why my complier cannot locate the RequestDispatcher?
根据建议，我在CLASSPATH中删除了分号并更改为冒号，还只需运行 javac -verbose RegisterServlet.java 即可
As per suggestion, I've removed semi-colon and change to colon in my CLASSPATH and also simply run javac -verbose RegisterServlet.java and it complied successfully.
推荐答案
javac -verbose -cp .:/home/makun/tomcat/apache-tomcat-6.0.26/lib ./RegisterServlet.java
您正在重写CLASSPATH env这里可变。您似乎还用; 分隔类路径条目，在* nix上，您可能需要：。如果您的CLASSPATH env变量是已导出，请这样做
You're overriding the CLASSPATH env variable here. You also seem to seperate the classpath entries with a ; , on *nix you might need a : instead. If your CLASSPATH env variable is exported, just do
javac -verbose RegisterServlet.java
或
javac -cp $CLASSPATH -verbose RegisterServlet.java
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