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所以我最近了解了泛型,並認爲在優先級隊列中實現它們會很酷。我有一個「Block」元素,它有一個firstName和一個數據變量。優先級隊列的節點由Block,Next和Prev組成。Priority Queue通用
我附上下面的代碼。我幾乎完全得到「應該參數化」的錯誤/警告。還有一個錯誤,說我的「數據」元素無法解析到一個字段,這可能意味着我無法告訴我要阻止我在節點中的「元素E」。任何建議將深表讚賞
package QGen;
public class Block<E> implements Comparable<Block<E>> {
protected String firstName;
protected int data;
public Block(String firstName, int data) {
super();
this.firstName = firstName;
this.data = data;
}
@Override
public int compareTo(Block x) {
return (this.data - x.data);
}
}
package QGen;
public class PriorityQueue<E extends Comparable> {
protected Node<E> firstSentinel;
protected Node<E> lastSentinel;
protected class Node<E> {
protected Node<E> next;
protected Node<E> prev;
private E element;
public Node(E e, Node<E> previous, Node<E> nextt) {
element = e;
prev = previous;
next = nextt;
}
}
public PriorityQueue() {
firstSentinel = new Node<>(null, null, null);
lastSentinel = new Node<>(null, null, null);
firstSentinel.data = 11111;
lastSentinel.data = 0;
firstSentinel.prev = null;
firstSentinel.next = lastSentinel;
lastSentinel.prev = firstSentinel;
lastSentinel.next = null;
}
public void enQueue(E x) {
Node<E> newX = new Node<E>(x, null, null);
if (firstSentinel.next == lastSentinel)// list is empyty
{
firstSentinel.next = newX;
newX.prev = firstSentinel;
newX.next = lastSentinel;
lastSentinel.prev = newX;
} else {
Node<E> temp = newX;
Node<E> curr = firstSentinel.next;
while (curr != lastSentinel && temp.element.compareTo(curr) <= 0) {// <=comparison
// replaced
curr = curr.next;
}
Node<E> tempCurr = curr;
temp.next = tempCurr;
temp.prev = tempCurr.prev;
tempCurr.prev.next = temp;
tempCurr.prev = temp;
}
}
public E deQueue() {
if (firstSentinel.next == lastSentinel) {
return null;
} else {
Node<E> temp = new Node<E>(null, null, null);
temp = firstSentinel.next;
firstSentinel.next = temp.next;
temp.next.prev = firstSentinel;
return temp.element;
}
}
public void printt() {
Node<E> temp = new Node<E>(null, null, null);
temp = firstSentinel.next;
while (temp != lastSentinel) {
System.out
.println(temp.element.firstName + " " + temp.element.data);
temp = temp.next;
}
}
}
package QGen;
public class containsMain<E> {
public static void main(String[] args) {
PriorityQueue<Block> example = new PriorityQueue<Block>();
Block dequedObject = new Block<>(null, null);
Block<Block> incomingName = new Block<>("r", 1);
example.enQueue(incomingName);
dequedObject = (Block) example.deQueue();
}
}
我知道我的PriorityQueue可能不是最好的實現,我會改進它。這就是我不能拿出一個解決方案
感謝