why can't my arraycopy work???

[ming ming]

   
public class FishClass {
    int numberOfFish=0;
    protected int fishAmount=10;
    Fish[] fish=new Fish[fishAmount];
   
    public void setFish(String name,int age){           
        if(full()){
        Fish[]newFish=new Fish[fishAmount*20];   
        System.arraycopy(fish,0,newFish,0, newFish.length);//Arraycopy can't                                                           //   work here
        for(int x=0;x<newFish.length;x++){
        System.out.println(newFish[x]);
        }
        fish=newFish;
    //resize();
         }       
        fish[numberOfFish]=new Fish();
        fish[numberOfFish].setName(name);
        fish[numberOfFish].setAge(age);
        numberOfFish++;       
}
 
    private boolean full(){
    return numberOfFish==fishAmount;
    }
    public Fish getFish(int x){
   return fish[x];
    } 
}
 
 

when i pass in more than 10 it will show me indexoutofbound...didn't i have the arraycopy method... :roll:

[Keith Lynn]

Look at what the last parameter of arraycopy represents.

[ming ming]

what shall i put then??

[Pinkal Patel]

fish.legth instade of newFise.legnth

[ming ming]

i dun get it..y must we put fish.length instead of newFish.length..can someone explain 2 me??

[Pinkal Patel]

What is the length of newfish Array ?
and What is the length of fish Array ?

If your loop is moving as much time as length of newfish what happen....


it will try to acces fish[newFish.length-1 ] which will throws Exception

[wise owen]

    
public class FishClasss {
    int numberOfFish=0;
    protected int fishAmount=10;
    Fish[] fish=new Fish[fishAmount];
 
    public void setFish(String name,int age) {
       if(full()){
          [B]fishAmount *= 20;[/B] 
          Fish[]newFish=new Fish[fishAmount];
          [B]System.arraycopy(fish,0,newFish,0, fish.length);[/B]
          for(int x=0;x<newFish.length;x++){
             System.out.println(newFish[x]);
          }
          fish=newFish;
       }
      fish[numberOfFish]=new Fish();
      fish[numberOfFish].setName(name);
      fish[numberOfFish].setAge(age);
      numberOfFish++;
    }
    private boolean full() {
    return numberOfFish==fishAmount;
    }
    public Fish getFish(int x){
   return fish[x];
    }
    
}

[Bert Bates]

For those of you keeping score, you won't have to worry about the System.arraycopy method, it's not on the exam - yea!