如何在java中编译和执行包文件 [英] How to compile and execute a package file in java
问题描述
我正在从'Java2:Schield的完整参考资料'学习Java。我正在使用带有命令提示符(JDK)的Windows 7系统来编译和执行Java程序。我正在尝试编译一个包含程序包的程序,如下面的代码所示:
import java。 AWT *。
package MyPack;
class 余额
{
字符串名称;
double bal;
余额(字符串 n, double b)
{
name = n;
bal = b;
}
void show()
{
if (bal< 0)
{
System.out.print( - > 跨度>);
System.out.println(name + :$ + bal);
}
}
}
class 帐户
{
public static void main(字符串 args [])
{
余额当前[] = 新余额[ 3 跨度>];
当前[ 0 ] = new 余额( KJ Fielding, 123 。 23 跨度>);
当前[ 1 ] = new 余额( 将告诉, 157 。 02 跨度>);
当前[ 2 ] = new 余额( Tom Jackson, - 12 。 33 跨度>);
for ( int i = 0 ; i< 3 ; i ++)current [i] .show();
}
}
当我执行
>C: \Program Files\Java\jdk1.7.0_25\bin\javacAccount.java(来自MyPack文件夹
或
> C:\Program Files\Java\jdk1.7.0_25\bin\javacMyPack / Account.java(在MyPack文件夹之外),
我收到以下错误:
Account.java:2:错误:类,接口或枚举预期包MyPack;
或
MyPack \Account.java:2:错误:类,接口或枚举预期包MyPack;< br $> b $ b
请让我知道如何编译然后执行这样的程序?
什么我试过了:
我试过从MyPack文件夹里面以及在我之外编译程序,如上面的查询中所述。
+ bal);
}
}
}
class 帐户
{
public static void main(字符串 args [])
{
余额当前[] = 新余额[ 3 跨度>];
当前[ 0 ] = new 余额( KJ Fielding, 123 。 23 跨度>);
当前[ 1 ] = new 余额( 将告诉, 157 。 02 跨度>);
当前[ 2 ] = new 余额( Tom Jackson, - 12 。 33 跨度>);
for ( int i = 0 ; i< 3 ; i ++)current [i] .show();
}
}
当我执行
>C: \Program Files\Java\jdk1.7.0_25\bin\javacAccount.java(来自MyPack文件夹
或
> C:\Program Files\Java\jdk1.7.0_25\bin\javacMyPack / Account.java(在MyPack文件夹之外),
我收到以下错误:
Account.java:2:错误:类,接口或枚举预期包MyPack;
或
MyPack \Account.java:2:错误:类,接口或枚举预期包MyPack;< br $> b $ b
请让我知道如何编译然后执行这样的程序?
什么我试过了:
我已经尝试从MyPack文件夹中以及在我之外编译程序,如上面的查询中所述。
包
州议员t应该在import
之前。请参阅 Java™教程 [ ^ ]。
I am learning Java from ‘Java2: The Complete Reference by Schield". I am using a Windows 7 system with command prompt (JDK) to compile and execute Java programs. I am trying to compile a program having a package as seen in the code below:
import java.awt.*;
package MyPack;
class Balance
{
String name;
double bal;
Balance(String n, double b)
{
name = n;
bal = b;
}
void show()
{
if(bal<0)
{
System.out.print("--> ");
System.out.println(name + ": $" + bal);
}
}
}
class Account
{
public static void main(String args[])
{
Balance current[] = new Balance[3];
current[0] = new Balance("K. J. Fielding", 123.23);
current[1] = new Balance("Will Tell", 157.02);
current[2] = new Balance("Tom Jackson", -12.33);
for(int i = 0; i < 3; i++) current[i].show();
}
}
When I execute either
>"C:\Program Files\Java\jdk1.7.0_25\bin\javac" Account.java" (from within the MyPack folder"
or
>"C:\Program Files\Java\jdk1.7.0_25\bin\javac" MyPack/Account.java (outside the MyPack folder),
I receive the following error:
" Account.java:2: error: class, interface, or enum expected package MyPack;"
Or
"MyPack\Account.java:2: error: class, interface, or enum expected package MyPack;"
Please let me know how I can compile and then execute such a program?
What I have tried:
I have tried compiling the program from inside the MyPack folder as well as outside it as explained in my query above.
" + bal); } } } class Account { public static void main(String args[]) { Balance current[] = new Balance[3]; current[0] = new Balance("K. J. Fielding", 123.23); current[1] = new Balance("Will Tell", 157.02); current[2] = new Balance("Tom Jackson", -12.33); for(int i = 0; i < 3; i++) current[i].show(); } }
When I execute either
>"C:\Program Files\Java\jdk1.7.0_25\bin\javac" Account.java" (from within the MyPack folder"
or
>"C:\Program Files\Java\jdk1.7.0_25\bin\javac" MyPack/Account.java (outside the MyPack folder),
I receive the following error:
" Account.java:2: error: class, interface, or enum expected package MyPack;"
Or
"MyPack\Account.java:2: error: class, interface, or enum expected package MyPack;"
Please let me know how I can compile and then execute such a program?
What I have tried:
I have tried compiling the program from inside the MyPack folder as well as outside it as explained in my query above.
Thepackage
statement should come before theimport
. See The Java™ Tutorials[^].
这篇关于如何在java中编译和执行包文件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!