这是一个接口的方法,我必须在另一个类中实现,我不知道如何创建它。我必须使用带有printStream参数的linkedList打印堆栈。在类Node(对于linkedList)中,我有一个方法getObject()。
import java.io.PrintStream;
import java.util.NoSuchElementException;
public interface StringStack {
public boolean isEmpty();
public void push(String item);
public String pop() throws NoSuchElementException;
public String peek() throws NoSuchElementException;
/**
* print the contents of the stack, starting from the item
* on the top,
* to the stream given as argument. For example,
* to print to the standard output you need to pass System.out as
* an argument. E.g.,
* printStack(System.out);
*/
public void printStack(PrintStream stream);
public int size();
}
public class StringStackImpl implements StringStack {
private Node head;
....
public void printStack(PrintStream stream) {???}
}
答案 0 :(得分:0)
不确定堆栈的结构如何,但应该这样做:
Node node = head; // top of the stack
while(node != null){
stream.println(node.value);
stream.flush();
node = node.next;
}