自定義Java棧類，並實現進制轉換

Java棧類實現：

public class StackExercise {
    Object[] stacks; // 棧容器
    int size; // 棧容量
    int top; // 記錄位置
    int len; // 棧實際成員數量

    public StackExercise(int size) {
        super();
        this.size = size;
        this.stacks = new Object[this.size];
        this.top = -1;
    }

    // 獲取棧頂元素
    public Object peek() {
        return this.stacks[top];
    }

    // 判斷棧是否為空
    public boolean isEmpty() {
        return top == (-1);
    }

    // 判斷棧是否已滿
    public boolean isFull() {
        return top == (size - 1);
    }

    // 入棧過程
    public void push(Object value) {
        len++;
        stacks[++this.top] = value;
    }

    // 出棧過程
    public Object pop() {
        len--;
        return stacks[this.top--]; // 注意這里不能用“--this.top”，會導致棧溢出
    }

    // 獲取棧實際大小
    public int len() {
        return this.len;
    }

}

實現進制轉換：

public class TestStack {

    // 二進制轉換方法
    public static String toJinzhi(int num) {
        StackExercise stack = new StackExercise(32);
        while (num > 0) {
            stack.push(num % 2);
            num = num / 2;
        }
        StringBuffer sBuffer = new StringBuffer();
        while (!stack.isEmpty()) {
            sBuffer.append(stack.pop());
        }
        return sBuffer.toString();
    }

    // 通用進制轉換方法
    public static String baseConvert(int num, int base) {
        StackExercise stack = new StackExercise(32);
        while (num > 0) {
            stack.push(num % base);
            num = num / base;
        }
        String dights = "0123456789abcdef";
        StringBuffer sBuffer = new StringBuffer();
        while (!stack.isEmpty()) {
            sBuffer.append(String.valueOf(dights.charAt((int) stack.pop())));
        }
        return sBuffer.toString();
    }

    public static void main(String[] args) {
        System.out.println(toJinzhi(123456789));
        System.out.println(baseConvert(255, 2));
    }

}