Java final与泛型详细解析

示例代码：
//入栈操作↓
void push(int value){
    top++;
    arr[top]=value;
}
//出栈操作↓
void pop(){
    println(arr[top]);
    top--;
}

public class Stack<哈基米>{
    private 哈基米 arr[];
    private int top;
    public Stack(int size){
    arr=(哈基米[])new Object[size];//强转换
    top=-1;
}
public void push(哈基米 value){
    if(top==arr.length-1){
        System.out.println("栈已满")
        return;
       }
     arr[++top]=value;
}
public void pop(){
    if(top==-1){
    System.out.println("栈已空");
    return;
    }
}
System.out.println(arr[top--]);
}

public static void main(String[] args){
//整形
Stack<Integer> stack=new Stack<>(size:10);
    stack.push(value:1);
    stack.push(value:2);
    stack.push(value:3);
    stack.push(value:4);
    stack.pop();
    stack.pop();
//字符串
Stack<String>stack1=new Stack<>(size:10);
    stack1.push(value:"张三");
    stack1.push(value:"李四");
    stack1.push(value:"王五");
    stack1.pop();
    stack1.pop();
//浮点型
Stack<Double> stack2=new Stack<>(size:10);
    stack2.push(value:1.1);
    stack2.push(value:1.1);
    stack2.pop();
}
}
//输出为 4
        3
        2
        王五
        李四
        2.2

public static Integer valueOf(int i){
    if(i>=IntegerCache.low&&i<=IntegerCache.high)
    return IntegerCache.cache[i+(-IntegerCache.low)];
    return new Integer(i);
}

Integer i=127;
Integer j=127;
System.out.println(i==j);//true
Integer k=128;
Integer l=128;
System.out.println(k==l);//false