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class Animal{}
class Fish extends Aniaml{}
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class Fish extends animal
{
void output()
{
System.out.println("Fish");
}
}
//×ÓÀà
class SmallFish extends Fish
{
void output()
{
super.output();
System.out.println("SmallFish");
}
}
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classname variable;
variable = new classname();//********ÓÐ()
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import java.io.*;
class FileTest
{
public static void main(String[] args) throws Exception
{
//File f=new File("1.txt");
//f.createNewFile();
//f.mkdir();
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