Alguém poderia me ajudar??? Está dando esta mensagem:
[color=blue]Exception in thread "main" java.lang.NullPointerException
at pointer_jumping.Pointer_Jumping.run(Pointer_Jumping.java:13)
at pointer_jumping.Tester.main(Tester.java:13)[/color]
Minhas classes são estas:
package pointer_jumping;
class Pointer_Jumping implements Runnable {
private String threadName;
private Arvore arv;
public Pointer_Jumping(String name){
threadName = name;
}
public void run(){
for (int i=0; i< arv.parent.length; i++ ){
while (arv.parent[i] != arv.parent[arv.parent[i]])
arv.parent[i]= arv.parent[arv.parent[i]];
arv.imprime(i);
}
}
}
package pointer_jumping;
import java.util.Scanner;
public class Arvore {
// Vetor que representa uma árvore.
int parent[];
int num_vertices;
Arvore(int tamanho) {
parent = new int[tamanho];
num_vertices = tamanho;
}
public void setParent(){
for (int i=0; i < parent.length ;i++){
System.out.println("Diga o vizinho do nó "+i+":");
Scanner teclado = new Scanner(System.in);
parent[i]= teclado.nextInt();
}
}
public void imprime(int no){
System.out.println("Nó "+no+ " possui vizinho "+parent[no]);
}
}
package pointer_jumping;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class Tester {
public static void main(String[] args) {
Arvore arv = new Arvore(6);
Pointer_Jumping pj1 = new Pointer_Jumping("thread1");
pj1.run();
}
}
