hi there,

I am stuck at somewhere same.

/* ISPN.java
* A class to represent an imaginary "International Standard Program Number"

*/

package tma01q1;

public class ISPN
{
private int[] authorId;
private int[] programId;

/**
* Creates a new instance of ISPN
*/
public ISPN(int[] anAuthorId, int[] aProgramId)
{
authorId = anAuthorId[] ;
programId = aProgramId[] ;
}

public boolean isValidLength()
{
if ((authorId.length + programId.length) == 6)


return true;

}

public boolean isAllValidDigits()
{
// TODO
return false;
}

public String getAuthorIdAsString()
{
// TODO
return null;
}

public String getProgramIdAsString()
{
// TODO
return null;
}

public int calculateCheckDigit()
{
// TODO
return 0;
}

public String toString()
{
// TODO
return null;
}

public boolean equals(ISPN ispn)
{
// TODO
return false;
}
}