Java编译环境搭建问题，无法运行Hello word - V2EX
Home Sign Up Sign In
wudoo59
V2EX    Java

Java编译环境搭建问题，无法运行Hello word

  •   
  •   wudoo59 Apr 8, 2011 7021 views
    This topic created in 5513 days ago, the information mentioned may be changed or developed.
    编译最简单的程序“Hello World”就这样：

    Exception in thread "main" java.lang.NoClassDefFoundError: Welcome
    Caused by: java.lang.ClassNotFoundException: Welcome
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
    Could not find the main class: Welcome. Program will exit.

    只设置了环境变量：path：C:\Program Files\Java\jdk1.6.0_24\bin

    然后我编译的程序在D:/javaTest 目录下

    根据网上的方法设置classpath 依然无效。 JDK版本1.6.0
  • Java
  • lang
  • URLClassLoader
    12 replies    1970-01-01 08:00:00 +08:00
    chone
        1
    chone  
       Apr 8, 2011
    文件名是Welcome.java?另外有没有package
    wudoo59
        2
    wudoo59  
    OP
       Apr 8, 2011
    @chone 没有package 文件名是Welcome.java

    public class welcome{
    public static void main(String[] args){
    System.out.println("Welcome to java!");
    }
    }
    billychow
        3
    billychow  
       Apr 8, 2011
    注意大小写！
    wudoo59
        4
    wudoo59  
    OP
       Apr 8, 2011
    @billychow

    错了 ，代码是

    public class Welcome{
    public static void main(String[] args){
    System.out.println("Welcome to java!");
    }
    }

    大小写没有问题
    yinwm
        5
    yinwm  
       Apr 8, 2011
    还是怀疑在执行时候classpath的问题，你classpath是怎么设置的？
    wudoo59
        6
    wudoo59  
    OP
       Apr 8, 2011
    @yinwm

    CLASSPATH %JAVA_HOME%\lib;.
    JAVA_HOME C:\Program Files\Java\jdk1.6.0_24
    path %JAVA_HOME%\bin;
    yinwm
        7
    yinwm  
       Apr 8, 2011
    你在执行java的时候 -cp 然后给classpath试试看，因为上面那样设置CLASSPATH，那里的 . 会指向哪里可能有问题
    Paranoid
        8
    Paranoid  
       Apr 8, 2011
    @wudoo59 classpath Or path 缺少 .(点)？ 代表当前目录
    doyle
        9
    doyle  
       Apr 8, 2011
    Welcome.class生成了吗？
    darasion
        10
    darasion  
       Apr 8, 2011
    嗯嗯。记得这个就是目录缺点儿 “.” 的问题。

    但是据说新的java都默认加点了啊。
    roamlog
        11
    roamlog  
       Apr 8, 2011
    classpath 设置为 .; 即可,其它的都不用添加...
    wudoo59
        12
    wudoo59  
    OP
       Apr 8, 2011
    已经弄好了。谢谢大家了。貌似是我空格了
    About     Help     Advertise     Blog     API     FAQ     Solana     3735 Online   Highest 6679       Select Language
    创意工作者们的社区
    World is powered by solitude
    VERSION: 3.9.8.5 42ms UTC 04:30 PVG 12:30 LAX 21:30 JFK 00:30
    Do have faith in what you're doing.
    ubao msn snddm index pchome yahoo rakuten mypaper meadowduck bidyahoo youbao zxmzxm asda bnvcg cvbfg dfscv mmhjk xxddc yybgb zznbn ccubao uaitu acv GXCV ET GDG YH FG BCVB FJFH CBRE CBC GDG ET54 WRWR RWER WREW WRWER RWER SDG EW SF DSFSF fbbs ubao fhd dfg ewr dg df ewwr ewwr et ruyut utut dfg fgd gdfgt etg dfgt dfgd ert4 gd fgg wr 235 wer3 we vsdf sdf gdf ert xcv sdf rwer hfd dfg cvb rwf afb dfh jgh bmn lgh rty gfds cxv xcv xcs vdas fdf fgd cv sdf tert sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf sdf shasha9178 shasha9178 shasha9178 shasha9178 shasha9178 liflif2 liflif2 liflif2 liflif2 liflif2 liblib3 liblib3 liblib3 liblib3 liblib3 zhazha444 zhazha444 zhazha444 zhazha444 zhazha444 dende5 dende denden denden2 denden21 fenfen9 fenf619 fen619 fenfe9 fe619 sdf sdf sdf sdf sdf zhazh90 zhazh0 zhaa50 zha90 zh590 zho zhoz zhozh zhozho zhozho2 lislis lls95 lili95 lils5 liss9 sdf0ty987 sdft876 sdft9876 sdf09876 sd0t9876 sdf0ty98 sdf0976 sdf0ty986 sdf0ty96 sdf0t76 sdf0876 df0ty98 sf0t876 sd0ty76 sdy76 sdf76 sdf0t76 sdf0ty9 sdf0ty98 sdf0ty987 sdf0ty98 sdf6676 sdf876 sd876 sd876 sdf6 sdf6 sdf9876 sdf0t sdf06 sdf0ty9776 sdf0ty9776 sdf0ty76 sdf8876 sdf0t sd6 sdf06 s688876 sd688 sdf86