hello i am beginner to java i wrote a simple program of object array but it is showing run time error
Exception in thread "main" java.lang.NullPointerException
at classarr.main(classarr.java:14)
class abc{
int i;
}
class classarr{
public static void main(String arg[])
{
abc a[]=new abc[4];
int j;
for(j=0;j<=3;j++)
a[j].i=j+1;
for(j=0;j<=3;j++)
System.out.print(a[j].i);
}
}please help me
Jump to Postabc a[]=new abc[4];
creates an array of reference variables that can refer to abc objects, but it doesn't populate those references with anything, so the initial values in that array are like {null, null, null, null}.
You need to create four new abc instances for the four array elements, eg
…
abc a[]=new abc[4];
creates an array of reference variables that can refer to abc objects, but it doesn't populate those references with anything, so the initial values in that array are like {null, null, null, null}.
You need to create four new abc instances for the four array elements, eg
for(j=0;j<=3;j++) a[j]= new abc();
can you please give me one example.
I did - last line of previous post.
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