如何在java中编译包？ [英] How to compile packages in java?

问题描述

我写了一个简单的程序包：

I have written a simple package program:

  //A simple package

       package MyPack


       class Balance
       {
        String name;
        double bal;

        Balance(String n, double b)
        {
            name=n;
                    bal=b;
            }

        void show()
            {
            if(bal<0)
            System.out.println("-->");
            System.out.println(name+ ": $:" +bal);
        }
        }

        class AccountBalance
        {
            public static void main(String args[])
            {
                       Balance current[]=new Balance[3];
                    current[0]=new Balance("A.K.Juwatkar",123.123);
                    current[1]=new Balance("A.P.Dhoke",345.67);
                    current[2]=new Balance("Anil Sarang",100.98);

                    for(int i=0;i<3;i++)
                current[i].show();
               }
        }

---

我正在使用Ubuntu 10.04&
当我使用

---

I am using Ubuntu 10.04 & When i compile it using

java MyPack.AccountBalance

我收到以下消息：

Exception in thread "main" java.lang.NoClassDefFoundError: MyPack/AccountBalance
Caused by: java.lang.ClassNotFoundException: MyPack.AccountBalance
    at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
Could not find the main class: MyPack.AccountBalance. Program will exit.

有什么问题？请帮帮我。
我已经安装了openjdk，我还需要安装其他东西吗？
我正在使用Ubuntu 10.04，请帮助我

What is wrong? Please help me out. I have installed openjdk, do i need to install anything else?? I am using Ubuntu 10.04, kindly help me out

推荐答案

最好从外部编译和运行类包：

Best is to compile and run the classes from outside the packages :

首先用javac编译：

First you compile with javac :

$javac MyPack/AccountBalance.java

这将在MyPack文件夹中创建一个名为AccountBalance.class的新文件

this will create a new file in the MyPack folder called AccountBalance.class

然后你可以运行它：

$java MyPack.AccountBalance

顺便说一下：不鼓励包裹名称以大写字母开头。

By the way: it is discouraged to have package names start with a capital.

这篇关于如何在java中编译包？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！