Java中常用的數(shù)據(jù)結(jié)構(gòu)有棧和隊(duì)列，它們有著廣泛的應(yīng)用場(chǎng)景，例如算法實(shí)現(xiàn)、數(shù)據(jù)處理、網(wǎng)絡(luò)編程等。以下是Java棧和隊(duì)列的代碼實(shí)現(xiàn)。

// Java棧的實(shí)現(xiàn)
public class Stack {
private int[] arr;
private int top;
// 構(gòu)造函數(shù)，創(chuàng)建一個(gè)空棧
public Stack(int size) {
arr = new int[size];
top = -1;
}
// 進(jìn)棧
public void push(int data) {
if (top == arr.length - 1) {
throw new RuntimeException("Stack is full.");
}
arr[++top] = data;
}
// 出棧
public int pop() {
if (top == -1) {
throw new RuntimeException("Stack is empty.");
}
return arr[top--];
}
// 查看棧頂元素
public int peek() {
if (top == -1) {
throw new RuntimeException("Stack is empty.");
}
return arr[top];
}
// 判斷棧是否為空
public boolean isEmpty() {
return top == -1;
}
}
// Java隊(duì)列的實(shí)現(xiàn)
public class Queue {
private int[] arr;
private int front;
private int rear;
// 構(gòu)造函數(shù)，創(chuàng)建一個(gè)空隊(duì)列
public Queue(int size) {
arr = new int[size];
front = 0;
rear = -1;
}
// 進(jìn)隊(duì)
public void enqueue(int data) {
if (rear == arr.length - 1) {
throw new RuntimeException("Queue is full.");
}
arr[++rear] = data;
}
// 出隊(duì)
public int dequeue() {
if (front >rear) {
throw new RuntimeException("Queue is empty.");
}
return arr[front++];
}
// 查看隊(duì)頭元素
public int peek() {
if (front >rear) {
throw new RuntimeException("Queue is empty.");
}
return arr[front];
}
// 判斷隊(duì)列是否為空
public boolean isEmpty() {
return front >rear;
}
}