java newbie. some error

[x11]

hi! this is my code. i am getting the error given in the end. can any one help.
(i have just written the matrix multiplicartion. dont know if it works.)


class Mult
{
private int arr1[][] ={{1,2,3},{2,3,4},{4,5,6}};
private int arr2[][] ={{1,2,3},{2,3,4},{4,5,6}};

public static void main(String[] args)
{
System.out.println("Hello World!");
Matrix m = new Matrix();

m.PrintMatrix(arr1);

}
}

class Matrix
{
int Mat [][]=new int[3][3];
int tmp=0;
void Multiply(int arr1[][],int arr2[][])
{
for (int k=0;k<3 ;k++ )
{

for(int i=0;i<3;i++)
{
for (int j=0;j<3 ;j++ )
{
tmp+=arr1[k]*arr2[k][j];
}
Mat[k]=tmp;
tmp=0;

}
}
}
void PrintMatrix(int arr[][])
{

System.out.println("");
for (int i=0;i<3 ;i++ )
{

for(int j=0;j<3;j++)
System.out.print(arr[j]+ " ");
System.out.println("");
}

}


}
///////////////////////////////////////////////////
Mult.java:11: non-static variable arr1 cannot be referenced from a static contex
t
m.PrintMatrix(arr1);
^
1 error
////////////////////////////////////////////////////

[ArchAngel]

The compiler message says it all: you're trying to use non-static variables (i.e. those which are attached a particular instance of that class rather than the class itself) from a static portion of code (a portion of code which is associated with a class, not an instance of that class).

Solution: Declare the variables thus:

private static int arr1[][] ={{1,2,3},{2,3,4},{4,5,6}};
private static int arr2[][] ={{1,2,3},{2,3,4},{4,5,6}};

[x11]

hi!
kindly note that i am new to java;

in the abouve progrtam i pass non static members of a class to nonstatic member functin of another class. so why the problem.

Originally posted by ArchAngel
The compiler message says it all: you're trying to use non-static variables (i.e. those which are attached a particular instance of that class rather than the class itself) from a static portion of code (a portion of code which is associated with a class, not an instance of that class).

Solution: Declare the variables thus:

private static int arr1[][] ={{1,2,3},{2,3,4},{4,5,6}};
private static int arr2[][] ={{1,2,3},{2,3,4},{4,5,6}};

[ArchAngel]

arr1 and arr2 are non-static instance variables of the Mult class.

In the *static* method of the Mult class, there is some code (the code itself is irrelevant) which makes reference to the *non-static* instance variable arr1.

--

OK. The important point here is that it doesn't matter if you're passing the variables to an object instance. The important point is that you're trying to pass those *non-static* variables from a *static* context (the main method).