Answer:
Java Class given below
Explanation:
class ReadOnly
{
protected int val;
public ReadOnly(int arg)
{
val = arg;
}
public int getVal()
{
return val;
}
}
class ReadWrite extends ReadOnly
{
private boolean dirty;
public ReadWrite(int arg)
{
super(arg);
dirty = false;
}
public void setVal(int arg)
{
val = arg;
dirty = true;
}
public boolean isDirty()
{
return dirty;
}
}
