大家好,我java初学,下了一个J2SE5.0,然后写了一个程序,如下:
import javax.swing.JOptionPane;
public class hn
{public static void main(String[] args)
{JOptionPane.showMessageDialog(null,"I love xue","ning and xue");
}
}但是我用UltraEdit编译时候出现以下问题:hn.java:4: cannot find symbol
symbol : method showMessageDialog(<nulltype>,java.lang.String,java.lang.String)
location: class javax.swing.JOptionPane
{JOptionPane.showMessageDialog(null,"I love xue","ning and xue");
^
1 error然后我去找了一个网站下了一个javax包,里面有swing类库,但是我不知道把它放哪里好,请高手们指教,我对java非常感兴趣!
import javax.swing.JOptionPane;
public class hn
{public static void main(String[] args)
{JOptionPane.showMessageDialog(null,"I love xue","ning and xue");
}
}但是我用UltraEdit编译时候出现以下问题:hn.java:4: cannot find symbol
symbol : method showMessageDialog(<nulltype>,java.lang.String,java.lang.String)
location: class javax.swing.JOptionPane
{JOptionPane.showMessageDialog(null,"I love xue","ning and xue");
^
1 error然后我去找了一个网站下了一个javax包,里面有swing类库,但是我不知道把它放哪里好,请高手们指教,我对java非常感兴趣!
你可以google一下类似的问题
// JOptionPane.showMessageDialog(null,"I love xue","ning and xue");
JOptionPane.showMessageDialog(null, "Hello");
}
}俺这程序可以运行哦 ,你的环境没配置好.
//JOptionPane.showMessageDialog(null,"I love xue","ning and xue");
JOptionPane.showMessageDialog(null, "Hello");
}
}
这段程序编译成功,但是在运行时出现了这样的问题:
java.lang.NoClassDefFoundError: HelloWorld (wrong name: org/bign/HelloWorld)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
Exception in thread "main"
....这是为什么?
UltraEdit的使用方法:
写入程序,然后在"高级"配置中打开"dos命令";
编译时候在命令处输入javac."文件名字".java,然后运行时候输入java."文件名字",就可以了. 那个输出目录好象只要在java的安装目录下就可以了.