代码如下:
class Printing{
public static void main(String args[]){
for(int i=1;i<=5;i++){
for(int j=1;j<=5;j++){
System.out.print("#");
}
System.out.println();
}
}
}
错误如下:
G:\java_lesson\Ch1>javac printing.javaG:\java_lesson\Ch1>java printing
Exception in thread "main" java.lang.NoClassDefFoundError: printing (wrong name:
Printing)
at java.lang.ClassLoader.defineClass0(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)G:\java_lesson\Ch1>
class Printing{
public static void main(String args[]){
for(int i=1;i<=5;i++){
for(int j=1;j<=5;j++){
System.out.print("#");
}
System.out.println();
}
}
}
错误如下:
G:\java_lesson\Ch1>javac printing.javaG:\java_lesson\Ch1>java printing
Exception in thread "main" java.lang.NoClassDefFoundError: printing (wrong name:
Printing)
at java.lang.ClassLoader.defineClass0(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)G:\java_lesson\Ch1>
保存时应该是Printing.java
然后再javac Printing.java
java Printing
public class TranslateVariable{
public static void main(String args[])
{int i1=10;
float f1=3.14f;
double d1=3.1415926;
Integer I1=new Integer(i1);
Float F1=new Float(f1);
Double D1=new Double(d1);
String s1=I1.toString();
String S2=F1.toString();
String S3=D1.toString();
System.out.println("s1"+" "+s1);
System.out.println("s2"+" "+s2);
System.out.println("s3"+" "+s3);
}
}
帮我看看:
public class InputTest{
public static void main(String args[])
{
String name=JOptionPane.showInputDialog("please input your name!");
String input=JOptionPane.showInputDialog("please input your age!");
int age=Integer.parseInt(input);
System.out.println("Hello,"+name+". your age is:"+age);
System.exit(0);
}
}